Asparagus care calendar: Keep asparagus moist but not wet when the spears are forming.
Asparagus is among the earliest and tastiest crops each year. Perennial asparagus beds can produce spears for decades and decades with proper care through the years.
Plant asparagus where there is plenty of sun in the spring and the soil is rich in organic matter and well drained. As a guide, you will need about 20 to 40 crowns for each person; 20 for the spring harvest and more for a second or third harvest later in the season.
Keeping the asparagus patch productive will require a few simple tasks each season.
Here is a season-by-season guide for asparagus growing and care:
Spring. Asparagus spears will be ready for harvest shortly after the soil temperature reaches 50°F in early spring—that’s when spears will begin to emerge. Two week before spears begin breaking through the soil, pull the winter mulch back and cultivate the asparagus patch lightly loosening the soil and uprooting weeds.
Begin the harvest when spears are 6 to 8 inches long; that’s when they are most tender. Don’t let spears grow taller; they will become tough. Harvest spears daily during the harvest period; hand snap each spear off just below the soil surface.
Harvest will last 2 to 10 weeks depending upon the age of the plants. The first harvest year pick spears for 2 weeks; this will allow roots to become established and grow strong. Each year after, increase the spear harvest by a week.
Once spears have started to grow tall, weed the growing bed once more then place a 4 to 6 inch layer of straw or hay or dried grass around plants for the remainder of the harvest and growing season. Mulching after spears have emerged will keep weeds down and preserve soil moisture through the warm time of the year. Weeds that grow up through the mulch can be easily pulled by hand. An alternative is to sow annual rye grass around asparagus plants in spring. Rye grass will crowd out small weeds and will die off in winter.
Late spring. Plant for future asparagus harvests in late spring. Sow asparagus seed 1½ inches deep and 2 inches apart in loose, well-drained soil. Sow seed when the soil temperature is between 70 and 75°F. Seeds should emerge in 10 to 20 days. Keep the soil moist and control weeds. Later, thin plants to 12 inches apart.
Transplant asparagus crowns (one-year-old rhizomes) in spring about the same time you transplant out tomato plants. Set crowns at the bottom of a trench 10 to 12 inches deep and cover with 2 to 3 inches of soil. Set crowns 12 inches apart. As plants begin to grow cover the new growth with 2 inches of soil every few weeks until the trench is filled. When spears shoot up the first year, let them leaf out and grow on.
After harvest in spring, feed each plant an organic fertilizer to support top growth through the summer; summer growth will determine how good the following year’s spears will be. Aged compost and well-rotted manure will feed asparagus beds. (Add nutrients in spring before spears emerge and again after the last harvest.) A rich asparagus fertilizer is three parts greensand, two parts cottonseed meal, one part dried blood, and one part bone meal applied at the rate of 2 pounds per 50 square feet of bed.
During the warm season, keep weeds down with a thick layer of straw, hay, or dried grass clippings—fresh grass clippings contain too much moisture to use as a mulch without first drying; they can become slimy and moldy if applied freshly cut. Weeds will compete with asparagus plants for nutrients and diminish both yield and spear size.
Summer. After harvest, let the plant’s fernlike foliage grow tall. Summer growth allows asparagus roots to grow large and store energy for the following year’s spears. Stakes and string will keep plants upright. In breezy areas, plant rows parallel to the prevailing wind so that plants can support each other. Crowns grow upwards about 1 inch each year, so spreading compost across the planting bed or along rows in summer will both feed plants and raise the soil surface.
To get a second or more harvests each year, plant twice the number of plants or more needed for each person (40 rather than 20) then harvest only half of the bed in spring and let the other half grow on. In early summer, cut down the top growth in the half of the bed that was not harvested. This section will send up new spears in a few weeks that can be cut in late summer or early fall for a second harvest. If the growing bed is large enough, you can divide the bed into sections and use this method for a new 2 month harvest every 8 weeks, multiple asparagus harvests each year.
Late Fall and Winter. In mild winter regions, cut down ferny top growth after it has turned brown in late fall or winter. (Even in autumn, asparagus tops may look dead but are still storing energy for spear production the next spring.) In cold winter regions, don’t cut back top growth; let it provide extra protection for roots from freezing temperatures.
(You can allow asparagus berries to mature and drop each fall. In spring, thin out new plants started from dropped berries; allow some new plants to establish and replace older plants.)
Where you cut back top growth, mound 3 or 4 inches of soil over crowns or add 3 to 4 inches of aged manure and compost across the bed to protect roots from cold temperatures. An alternative is to mulch the bed with 8 inches of loose straw or hay and add phosphorus and potassium rich cottonseed meal and wood ashes across the mulch. Deep mulching is important in cold regions to protect asparagus from tip-kill in spring and feeding is important for future spear production. A decline in spears is commonly the result of lack of nutrients.
Adding 4 to 6 inches of aged compost over planting beds and asparagus crowns each year effectively increases the depth of the crowns which in turn increases spear size and tenderness the following spring. When spears become spindly, crowns may have grown too close together and older plants should be thinned out.
Leave winter mulch in place until the danger of a freeze has passed in late winter or early spring, then pull the mulch back and ready the bed for the spring harvest.
More tips at How to Grow Asparagus.
By: Joseph Masabni
Asparagus (Asparagus officinalis) is a highly desirable, early-spring vegetable best suited to the cooler areas of North and West Texas. It can also be grown in areas such as Dallas and Houston. It produces poorly in areas with mild winters and extremely long, hot summers. With proper care and in a suitable climate, an asparagus crown can last 15 to 25 years.
Asparagus is good source of vitamin A and C and minerals, and it tastes better when homegrown than when shipped into Texas from other areas.
Asparagus is dioecious, meaning that it has separate male and female plants. Grown for its stems or spears, asparagus yields 8 to 10 pounds or more per 100 square feet of bed if tended well. For most home gardeners, a 20-foot row or 100 square feet of bed is adequate for a family of four. That’s equivalent to 20 planted crowns or 10 pounds of harvested asparagus per season.
- Site selection
- Soil preparation
- Care during the season
- Cutting Asparagus Foliage Back In Autumn
- When to Cut Asparagus Back
- Why You Should Be Cutting Asparagus Back
- Other Autumn Asparagus Care
- History and Background
- Management and Care
- Clearing your Patch
- Pests and Diseases
- Storing Stalks
- Cooking and Eating
- The Taste of Spring
- Asparagus: Plant Care and Collection of Varieties
- Need Help?
- Asparagus in autumn? Meet the man behind its extended season
Because asparagus remains in the same place several years, it is important to select the right spot and prepare the seedbed well. Asparagus does best in full sunlight and deep, well-drained, sandy or light-textured soils. Asparagus plants make a good border around the edge of a garden or along a fence.
Before planting, make sure that the soil is free of trash, soil insects, and perennial weeds such as johnsongrass or bermudagrass. Avoid sites where yellow nutsedge grows, as this indicates poor drainage, which is unsuitable for asparagus production.
In late fall, spread a 3-inch layer of organic matter such as manure, rotted sawdust, or compost over the beds. Till or spade them to a depth of 10 to 12 inches, and turn the soil to cover all organic matter.
Asparagus grows well in high-pH soils and poorly if the soil pH is below 6.0. Test the soil before planting the beds and add lime if needed to adjust the pH to 6.5 to 7.5.
The hybrid asparagus cultivars ‘Martha Washington’, ‘UC 157’, ‘Jersey Giant’, and ‘Mary Washington’ produce better than the standard cultivars. Male asparagus cultivars such as Jersey types (‘Jersey Giant’, ‘Jersey Knight’, and ‘Jersey Supreme’) are more productive and resist disease better than the female cultivars (‘Washington’ types). Also, female cultivars are less vigorous and produce many red, berrylike fruits that become volunteer weeds in the garden.
A purple asparagus cultivar (‘Purple Passion’) with green flesh and large spears is available for home gardens.
Asparagus is grown from 1- or 2-yearold crowns planted in January or February, or as soon as the ground can be worked. Crowns can also be grown from seeds planted in flats or peat cups. It takes at least a year to grow a good crown. To shorten the period from planting to harvest, buy and plant healthy, vigorous, 1- or 2-year-old crowns from a nursery, garden center, or seed catalog.
After the asparagus beds are tilled, mark rows 5 feet apart. Dig a furrow 4 inches wide and 4 to 12 inches deep. Separate the crowns by size, and plant those of similar size together for best uniformity in spear size at harvest.
Spread super phosphate fertilizer (0- 46-0) as a band in the furrow at a rate of 2.0 pounds per 1,000 square feet or 0.75 ounce per 20-foot row. Place the crowns 12 to 14 inches apart in the furrow. Planting too closely can cause small spears. Wider planting results in larger spears but lower total yield. In loose soils, plant the crowns 6 to 12 inches deep; in heavier soils, plant them 4 to 6 inches deep (Fig. 1). Cover the furrow with 1 inch of compost topped by 2 to 3 inches of soil. Firm the soil around the roots.
Over the season, fill the furrows gradually as the shoots grow. This covers small weeds, and they die from lack of light. By the end of the first season, the furrow should reach its normal level (Fig. 1). Control weeds, but do not injure the crowns. If the crowns are planted deeply, you can cultivate the bed with garden tools or tiller (do not till too deep) without damaging the crowns.
An alternative planting method is to plant the crowns at the suggested depth and immediately fill in the furrow with soil to its original level. Using this method, you do not need to gradually cover the crowns with soil, as long as the soil is not compacted over the newly planted crowns.
Figure 1. (a) Planting crown; (b) immediately after planting; (c) several weeks after planting; (d) at the end of the season
It takes 2 to 3 years from the time the crown is planted until the bed is in full production. When conditions are favorable, buds arise from the crown and develop into edible spears. If not harvested, the spears will develop into fernlike stalks. From these stalks, the mature plant manufactures food and stores it in the underground crown. This reserve supplies the energy necessary to produce spears the following year.
Before planting a new asparagus bed, broadcast and spade in or incorporate ¼ pound of nitrogen, phosphate, and potassium per 20 feet of row or as directed by a soil test report.
For established beds, scatter 2 pounds of 10-20-10 fertilizer (or its equivalent) per 20 feet of row before growth begins in the spring, late January, or early February in most areas of Texas.
After the last harvest, apply an additional 1 to 2 pounds per 20 feet of row. If available, use a nitrogen fertilizer such as 21-0-0 at this time. Always water the fertilizer into the soil.
Asparagus plants need frequent, deep watering. Water the beds thoroughly, and allow the top 1 inch of soil to dry before watering again. The time varies from 3 to 5 days, depending on soil type and temperature. In sandy soils, asparagus roots can reach 10 feet deep if adequate soil moisture is available.
Care during the season
Asparagus competes poorly with weeds. For asparagus to grow vigorously, weeds must be controlled in the first 1 to 2 years of its establishment. To suppress weeds, spread a 4- to 6-inch-thick layer of organic mulch, such as hay, stray, compost, wood chips, or grass clippings.
Asparagus beds require little care after the first 2 years of establishment. Keep weeds pulled or hoed from the beds. To avoid damaging the spears, control weeds early before the spears emerge. Till the soil when fertilizer is applied early in the season before the spears begin growing (Fig. 2).
Figure 2. Till the soil early in the season before the spears emerge.
At the end of the harvest season, control weeds by raking lightly or mulching. Apply fertilizer and till lightly 1 to 2 inches deep to kill weeds. Cover the bed with a 3-inch layer of clean straw, compost, or other mulch material. Water it thoroughly, and allow the asparagus to grow the rest of the year. This helps ensure a good harvest the next year (Fig. 3).
After the first hard frost or freeze of fall, cut off the fern tops at ground level and mulch the bed with manure. Burn or compost the fern tops to eliminate sources of insect eggs or disease reinfestation. In southern areas, the fern may not be killed by a freeze, so it should be removed in late November when the ferns turn yellow. Any spears that sprout may be removed and eaten.
The herbicide Roundup (glyphosate), available at garden centers, is best used as a broadcast application against weeds before asparagus growth begins in early spring or after the last harvest before ferns are allowed to develop. To avoid injuring the crown, make sure no spears are present when applying Roundup.
Harvest asparagus spears from established beds for about 8 weeks, depending on the area. Do not harvest during the first 2 years after planting. This waiting period enables the underground crown to grow and store enough reserves for a strong harvest for many years to come.
Harvest the spears when they are 4 to 10 inches long. To prevent the spears from becoming fibrous, harvest at least every other day. The fibrous condition is caused by over maturity or inadequate fertility. Spears with loose or opened heads are too mature.
To harvest, snap off the spears by hand at ground level. Never snap asparagus spears above the ground or allow a stub to remain.
An alternative method is to use a knife to cut the spears 1 to 2 inches below the soil level (Fig. 4). To avoid damage to the developing buds in the crown, never cut the spear too deep. However, this method is not recommended because the knife may spread diseases from crown to crown.
Figure 4. Some asparagus gardeners harvest by cutting the spears 1 to 2 inches below the ground level.
Stop harvesting when the spear diameter becomes less than 3 ⁄8 inch or when the spear heads open up with rising temperatures.
Some gardeners prefer white asparagus. This is grown by using mounds of soil or mulch to deprive the spears of light. White asparagus has a milder flavor and is preferred in gourmet cuisine. When the asparagus head barely emerges through the mulch mound, use a knife to cut the spears at the desired height.
White asparagus is grown by covering an asparagus row with black plastic supported by wire hoops. The covering is opened on one side for harvest, then placed into position again immediately after harvest. The plastic tunnel structure is removed when the harvest season is over. Culture and pest control of white asparagus are similar to that of green asparagus.
The most significant pest of asparagus is the asparagus beetle. Left unchecked, this beetle can greatly damage asparagus in a short period. The beetle overwinters (spends the winter) in crop residue or trash in the garden or in the border. If you see beetles feeding on asparagus, remove them by hand or spray them with Surround (organic insecticide) or Sevin.
If you select a good site with proper drainage and pH, you can reduce if not prevent the establishment of many asparagus diseases. Common diseases that attack asparagus are crown rot and rusts; they can be controlled with organic chemicals such as sulfur or potassium phosphite.
After harvest, asparagus loses quality very rapidly––the sugar content declines and the amount of fibrous material increases. Use spears with compact heads; those with loose heads are fibrous and do not keep well.
Asparagus can be stored up to 3 weeks in plastic bags in the refrigerator. For longer storage, blanch the asparagus spears 3 to 5 minutes, package, and freeze them.
For information on preserving and serving asparagus, contact the county Extension agent.
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Cutting Asparagus Foliage Back In Autumn
Growing and harvesting asparagus is a gardening challenge that requires patience and a little extra care to get started. One of the things that is important to asparagus care is preparing the asparagus beds for autumn and cutting the asparagus back.
When to Cut Asparagus Back
Ideally, asparagus should be cut back in the fall but it is important that you wait until all of the foliage has died back and turned brown or yellow. This will normally happen after first frost, but it can happen without frost in areas that do not receive frost. Once all of the foliage has died, cut the asparagus down to about 2 inches above the ground.
Why You Should Be Cutting Asparagus Back
It is a commonly held belief that cutting asparagus in the autumn will help to produce better quality spears the next year. This belief may or may not be true, but it could be tied to the fact that removing the old foliage helps to keep the asparagus beetle from overwintering in the bed. Cutting asparagus back also helps to reduce the chances of disease and other pests.
Other Autumn Asparagus Care
Once you have cut the asparagus back, add several inches of mulch to your asparagus bed. This will help to smother the weeds in the bed and will help fertilize the bed for next year. Compost or well rotted manure makes an excellent mulch for asparagus in autumn.
The above tips for autumn asparagus care apply to asparagus beds that are newly planted or well established.
Are you a fairly seasoned gardener, with a few notches on your belt?
Maybe you’ve already spent a few years growing annual crops for food: starting them from seed, tending young plants, and harvesting them – only to see them die and return to the soil again.
If you’ve seen many rounds of veggies come and go, it could be time for a little something different – such as planting asparagus, the king of perennial crops!
Especially if you have a nice, permanent corner of your garden that you’d never want to change (for at least 30 years), this could make an excellent home for this fern-like vegetable. You’ll be investing in a food source that comes back again and again, giving you fresh food year after year.
So when the end of the season arrives, you won’t have to say goodbye to ALL your hard work and plant companions that grow in warmer days. Asparagus will be here to stay – if you take good care of it!
In this article, we’ll give you a thorough guide on how to successfully introduce these delicious spears into your garden space – whether you’re a veggie veteran, or new to the game.
History and Background
Asparagus (Asparagus officinalis) has an interesting past.
While perusing several accounts of its history, I did find some debate over its true origins, though I’m sure the conflict is unintentional (and I’m still fascinated about where this discrepancy may have cropped up).
Fully flowering asparagus.
Some claim this cut-and-come-again veggie has ancestors hailing from boggy, lowland moors. Various growers I’ve talked with and other sources go so far as to say it’s a native of Scotland and the British Isles!
Even some prevailing gardening guides say that modern cultivars still prefer these swampy conditions, being similar to where they originated. Demanding constant moisture, they flourish in soggy areas where other vegetables would languish.
More credible sources, however, coupled with my own experiences growing asparagus, find this to be untrue. In fact, if you look up cultivating practices in Scotland, you’ll find that growing it in those regions can be quite a hassle.
While the vegetable’s spears do emerge in spring in response to rainfall, excess water and clammy cold is a real bane to asparagus. Its reanimation in spring requires a well-drained site, warmth, and average – not heavy – rainfall to get it going.
More likely, this fernlike distant relative of onions and garlic (once sharing the same family, Amaryllidaceae) is widely presumed to be local to the Mediterranean coastal regions of Europe and Asia – and you’ll find this mentioned more often than Scotland.
And while not a lover of cold and wet, this native coastal locale does explain its temperament that’s suited for sandier, saltier soils– something to keep in mind!
Unfolding asparagus bloom.
According to most historical accounts and online sources, the wild ancestor of asparagus was foraged and enjoyed principally by the ancient Greeks, and later the Romans around 200 B.C.E.
Beginning around that time, it was bred from a feral plant into the widespread, globally popular cultivated culinary victual that it is today. With more wild asparagus being found in countries like Italy and Greece than any other, it is pretty settled that these stalk-producing crowns are Mediterranean in origin.
During the Roman conquest in later years, growing and eating the delicious, tender shoots spread to the rest of the world and other parts of Europe. In many cultures, it didn’t just catch on as a food, but was also revered as a medicine.
The name of the plant is thought to come from Greek, though it is uncertain exactly what the Greek word roots might mean.
At one time though, the word asparagus transformed into a new folk term for the vegetable in English: “sparrow-grass,” a popular sobriquet still.
Moving on from the plant’s rich history, we enter into its interesting varieties – which happen to tie in some of its fascinating background as well.
In addition, the way asparagus is separated into different varieties sets it apart from most other vegetables. The types you can buy are designated by heirloom, open-pollinated, or male and female breeds on the one hand, or strictly all-male hybrids on the other.
What’s the difference between all-male and male/female?
Asparagus crowns grow as two different sexes, and their ability to pollinate can greatly detract from their productiveness in producing spears for food. All-male cultivars are greatly preferred since they don’t self-pollinate or divert that energy away from producing new stalks.
If your asparagus fronds produce bright red berries at the end of their season, you know you have an heirloom variety with females, but your production may be somewhat lower.
If you’re looking for a large yield, it’s recommended to start with an all-male hybrid. These almost always have the word Jersey in the name, due to the research that engineered these breeds at Rutgers University in New Brunswick, New Jersey.
All-male hybrids are likely to produce 2-3 times more than heirloom varieties on average.
Jersey Giant Asparagus Crowns available from Burpee
An early producer and one of the oldest developed varieties, does better in cool weather and yields large, thick spears.
Jersey Knight Asparagus Crowns available from Burpee
A popular choice, agrees with a wide variability of soils (including clay) and tolerates warmer climates.
Much like Jersey Knight, wide variability and performs well in warm climates.
Jersey Supreme Asparagus Crowns available from Burpee
Great producer and earlier than Giant, but pickier about being grown in sandy soil. Prefers cool weather.
These types will be less productive than their male counterparts, but nonetheless come with their own perks.
After all: if you want to breed your own kinds of asparagus, or even have your patch potentially reseed and spread, you’ll need some females!
Mary Washington seed and crowns available from Burpee
One of the oldest American heirloom varieties, Mary Washington still manages to be a high producer while including female plants.
An old traditional heirloom from Europe (particularly Italy), its stalks are perfect for blanching.
You might have seen white varieties at certain grocery stores or farmers markets. Perhaps the thought has crossed your mind: what exact variety produces white asparagus, and how do I go about growing it?
The answer: you can grow white asparagus from any variety you choose to propagate! This is done through a method called blanching, which restricts sunlight exposure to any stalk of any variety, thus whitening it – a method used with certain other delicious crops as well, like endive, cauliflower, and celery.
There are a few ways to do this:
The commercial method is through the use of special arched row covers over beds, which shield the plants from light in order to whiten them.
Another way is with a thick layer (2-3 feet) of loose straw mulch, placed over the beds before the spears emerge. This blocks a good portion of the sunlight, while allowing the spears to still rise into the material where they can then be harvested after removing the mulch.
While white spears are a more popular delicacy throughout regions of Europe, that doesn’t mean you can’t enjoy your very own from your garden or backyard anywhere else in the world!
While a purple variety of asparagus may seem like an offshoot all its own, in truth, purple types can be either open-pollinated/heirloom (male and female) or all-male hybrids.
When looking into purchasing crowns of this type, make sure to check the description and get the designated category you’re looking for (if any).
Otherwise, purple crowns are completely unique in their own way: they’re known for a sweeter taste, more tender texture, and – of course – they’re purple! However, the purple color does fade with cooking – but it will remain if used raw, in salads for example.
Purple Passion Asparagus Roots available on Amazon
Has the widest range of tolerance to weather, both hot and cold, among purple kinds – equivalent to purple Jersey Knight, tends to be an open-pollinated or heirloom variety.
Widely tolerable range like Purple Passion, but tends to come in an all-male hybrid variety.
When growing asparagus, the most popular method to starting your patch is by planting crowns.
Crowns are typically year-old, single root systems of the vegetable that can be replanted to start a new patch. You can order crowns online to get your own started.
Otherwise, you can begin asparagus from seed, though the method is much less successful, slower, and can yield more female plants than male – which may cut into how many spears you produce. In comparison, crowns are highly preferable.
It is best to get started with planting your crowns in the spring, after the last threat of frost and when the soil can be worked. This will give them enough time to build strength and become established throughout the whole warm season.
The steps required for doing so are quite simple:
1. Dig your bed
You can plant a few crowns next to one another in a row, or lay out a circle-shaped bed to give yourself a nice little patch.
If you choose the former, dig yourself a rut at least 8 inches to 1 foot deep to your desired length; if the latter, dig whatever area you wish to plant your crowns in to the same depth.
2. Determine size
How long or big should your bed be? This depends on how many crowns you plan to plant, as each should be spaced one foot from the other.
If digging a trench or rut in a row for 5 crowns, for example, you may want to prepare a bed with a 10-foot row. In a circular-shaped patch, make it ample enough to keep your plantings evenly spaced.
Add compost or your chosen fertilizer to the prepared bed, and work it into the ruts where you will be placing and planting your crowns.
When planting these singular root balls of asparagus, you will want to lay the root mass lengthwise into your rut, and take care that the actual “crown” – the knotty mass where all the roots join together – is planted face up. This is where the asparagus spears will emerge from, pushing their way up through the ground for harvest.
Of course, make sure to cover your crowns with a thick layer of earth in their ruts or bed. The actual crown (as discussed in the previous step) should lie somewhere between 6 inches and 1 foot below the surface of the soil.
The most necessary step for nearly all gardening projects: watering!
When first planting your asparagus crowns, give them a good, deep watering immediately after planting, and water more sporadically throughout the first season as needed (especially during dry periods and in hot, arid regions).
After watering, it’s a wise choice to mulch over your patch or row with a thick layer of organic matter – straw works best here. This adds a little extra nutrition, protection through cold weather, moisture retention, and reduction of weeds for less competition (and bigger spears).
After planting your crowns, your first season will consist of watching them grow as the months go by. If a crown establishes itself successfully, you will notice your very first small asparagus spears emerging.
They will most likely be very tiny – only pencil-thin in circumference, or thinner – and you will not want to pick them at all, at least for the first year.
Instead, it is best to let them grow tall, spreading out their feathery and fernlike foliage to fully establish and grow strong.
Some sources will state that freshly planted crowns must be left alone for at least 3 years, in order for the patch to fully establish.
You may do this just to be safe, and to make absolutely sure your patch will flourish – but after the first year, you may get away with harvesting just a few stalks off your young crowns.
Make sure you leave the vast remaining majority to their own devices for at least a couple more years to come, and that you follow the very best management and care tips to secure a healthy set of crowns for the future!
Management and Care
After you’ve planted your crowns and the fronds have begun to rise above the soil (or it’s the end of harvesting season, which we’ll get to in the next section), this opens up a new season to manage, maintain, and care for your mature patch in a number of ways.
The true blessing of growing asparagus: management of this perennial is typically light, and nowhere near as intensive as caring for certain other vegetables – like the needy tomato or head lettuce, for example!
Around the beginning of the year’s truly hot weather in your region (usually mid-June, though this may be later in far northern climes), you will likely start to notice that the stalks rising from your crowns are thinner, spindlier, and less appetizing-looking, though this is not always the case.
When this happens – due to hot weather, fewer quality stalks, or young crowns that need more time to mature – it’s time to leave them be, and allow them to grow into tall fronds.
Mature asparagus fronds.
This allows the whole plant to build its stores of energy, and readies it for a great harvest the next spring!
Sure, maybe you want to push and get the most harvest out of your patch if that’s the stage you’re at. But remember this tidbit of wisdom: the earlier your let your plants go to frond and flower, the healthier, more robust asparagus you’ll have next year!
Besides leaving the aboveground parts of the plant to grow (an easy task), what else can you do to help your patch along?
Clearing your Patch
According to Rosie Lerner, horticulturist from Purdue University, clearing all spears at the end of picking season gives you time to add extra mulch, remove weeds, and even amend with another feeding of compost or fertilizer before fronds grow their full height through summer.
Adding extra mulch over the beds when all spears are gone never hurts. A thick layer adds a bit more organic matter, nourishment, and moisture retention, and helps to keep lesser weeds down.
In some cases, you may have to clear small holes for your fronds to poke through when the start of picking season returns.
You can remove weeds from your patch whether there are no spears, harvestable spears, or towering fronds.
Once plants are plenty tall, however, you won’t need to worry too much about weeding – their height alone helps them out-compete other species in their bed (though removing large, towering weeds like thistle is important).
When fronds have not gotten too tall or crowded yet in their site, side dressing plants with compost or natural fertilizer (or, placing them right on top of the patch, if there are no aboveground spears present) will ensure that your plants get the adequate energy they’ll need to produce more delicious stalks next year – maybe even bigger ones!
As fronds tower over your patch (some over 6 feet), you can stake or trellis them if you like – though plants that have fallen over are not doing any damage to their health (in fact, falling over is how they spread their seeds).
A simple way to do this: drive stakes in the ground around the perimeter, and run string around plants so they don’t topple over.
Mowing and Clearing
Of course, once foliage dies back, you can clear it in preparation for the next season’s spears.
Clearing will take place in early winter or late fall, though you may wait until the very first signs of early spring to remove them. Mowing, cutting back, burning, or flame weeding all work great!
A blooming spear.
Pests and Diseases
While a hardy, hassle-free perennial, asparagus does suffer from some pests and diseases. While some of these only cause minor damage and not too much stress, it’s important all the same to check up on any potential issues from time to time.
A decimated asparagus patch will take a lot more time, work, and patience to restore to its former glory (sometimes even requiring fresh crown plantings) compared to the efforts required to ensure good pest management!
These are usually orange or orange-red and black, sometimes spotted, and they consume asparagus tips and ferns while laying eggs as well.
They can be removed with sprays (preferably organic), or introduction of a high population of natural predators (like some wasp species and lady beetles).
A small black fly that damages stems especially, giving them red, unappetizing markings.
Removal and suppression are helped by early removal of foliage in winter – as well as burning to reduce any carry-over larval population into next spring. Sprays (preferably organic) are available as well.
Iridescent-green or coppery-brown, these scarab-like beetles destroy above-ground foliage.
These can be kept away from your crops with preferably organic sprays, pheromone traps, or the introduction of natural predators (for example by attracting birds, or letting chickens run through the mature patch).
Closeup of bloom.
A fungus that afflicts root, crowns, and lower stems, it creates unattractive, damaging patches of red on stalks, yellows above-ground foliage, and reduces yields.
As this happens to stressed plants, preventive measures are the only key to avoiding the problem: ensuring adequate watering, reducing pests, avoiding crown damage, and avoiding close rotation with previous crowns are all necessary practices.
Purple spots on stalks and brown damage to ferns are the result of another fungal culprit.
Preferably organic sprays may help with spread. To prevent it, remove died-back foliage as early as possible, especially through burning.
This effects the foliage only, and appears as a change of color to yellow and brown, leading to foliage loss.
Burning and early removal of foliage is a great preventative, as well as ensuring that crowns are planted with ample space for maximum airflow, to reduce the spread of disease after removal of infected plants.
Once your planted, well cared for patch or row has grown tall for a season or two (sometimes over 6 feet, depending on the variety), the following spring brings your first round of thick, harvestable stalks.
As soon as the weather begins to warm consistently above 60°F and temperatures stay above freezing at night, the first tips of the year will begin poking up above the soil.
In order to get them growing to their ideal harvesting length – and to even get at them to harvest at all – you will need to clear away their tall foliage first. But it is important to do this at the right time.
Remove yellowed or browned foliage that has died back over the winter.
It can be pulled, cut, mowed, or even burned away or flame weeded to remove competition or add a little extra K (a.k.a. potassium).
Winter is Coming
Before the hard freeze sets in, the same as what was done in the spring can take place earlier in winter, but only after the tall foliage has completely died back and yellowed.
Cutting back green foliage can damage and shock the plant, rendering it less productive.
After the fernlike foliage is cleared away: it’s time for harvest!
As you first notice the spears rising from your planted crowns, it’s not quite time to harvest all of them at once.
Since single heads of asparagus will each emerge at different times (in other words, all spears won’t rise from the bed at once), you will have to assess each one for readiness by checking a few important details:
This can be determined by preference, but the ample length of most asparagus spears is 9 inches – though variety can weigh in on optimum length as well.
At this height or taller, the tips or buds will begin to open; any shorter, and your harvest will yield less product.
More so than length, size can be a matter of preference as well.
You can harvest spears of any thickness or circumference, large or small, and store them for eating. White asparagus tend to be stringier, and you may elect to peel some of the more fibrous outer layer from thicker stalks before cooking.
The purple, pointed tips are the most delectable part of the stalk; as it rises up, this bud unfolds into giant, feathery ferns and towering inedible foliage.
The ideal asparagus tip.
Pick stalks while the bud is still closed, or just barely clustered with small, whitish-yellow side-shoots – and before those too begin to branch off.
The more the tip opens, the less tender and tasty the stalks will be.
Spears should always be green with purple buds – or purple with white buds, if you’re growing a purple variety. Or, completely white if you are blanching them.
If spears look discolored or bruised, yellow or red, or even appear slightly translucent at the tip, this could be the result of early frost damage, and these will be inedible.
If you particularly fear frost damage, feel the stalks before you pick them. If stalks feel limp and pliable rather than supple and crisp, they have likely succumbed to frost damage and are no longer viable.
Stalks look good? Then it’s time to pick them – an easy task.
The best time to pick asparagus is during the morning and first half of the day.
On warmer days, you’ll see stalks getting taller and taller by the hour – so you’ll want to get them while they’re the optimum length, with bud tips still closed!
Here’s how to harvest:
- With one hand, move your fingers down to the very base of the stalk, right to where it rises above the soil.
- Using your thumb and forefinger, pinch the stalk at its bottom and bend it until it cleanly snaps away.
- If you don’t want to get your fingers dirty, you may use a knife to cut the stalk away from the earth, right above the soil.
Once you’ve picked all the stalks that are ready from your bed, you’ll want to store them correctly, with some good pointers to be explored in the next section.
Make sure not to keep them at room temperature or in the sun for too long afterward, or they’ll wilt and go limp!
The next day and throughout the rest of the season (ideally spring until mid-June, or summer solstice at the latest), keep an eye on your bed every morning for more harvestable stalks.
You’ll want to keep up a daily picking routine, so that stalks don’t open up to become the plant’s tall fronds. That’s something you’ll only want to happen towards the end of the asparagus season, and when there’s nothing left worth harvesting.
If your patch is successful and productive (especially if you have quite a few crowns), you could be pulling in a pretty good amount of delicious spears every day, week after week!
For that very reason, to make your asparagus patch worth all the work you put into it, you will want to store your asparagus correctly so you can make them go that extra mile. Here are some tips for your tips:
- Store spears bundled together, with all tips pointing the same way and cut/picked ends pointing the other. This helps to avoid unintentional damage to the tips during handling and in storage.
- Putting them in a plastic or paper bag in the fridge works well, though picking up and moving the bag can wear away or damage tips.
- Another alternative: a small food-grade wax box, which can be moved, opened, and shut without affecting the stalks, and a plastic bag draped over the stalks within the box to retain moisture.
- Stored correctly, spears can stay in great condition for up to about 2 weeks. To ensure maximum storage life, sprinkle a bit of water on the picked or sliced ends (not the tips) as soon as they get into the fridge, which helps rehydrate them.
- Leaving stalks in the fridge uncovered will dehydrate them – taking away flavor and texture, and making spears limp, mushy, and floppy. So make sure to store them correctly!
- Standing bunches of asparagus in water in the fridge is not recommended, as the ends can become soggy if you’ll be storing them for more than a couple of days.
Cooking and Eating
The highlight of growing asparagus is eating it!
So you’ve picked your first stash of spears, and you’re ready for a little home dining.
The most common way to prepare this garden delicacy is by sautéing those delicious tips (oh yes – especially the tips), maybe with that classic bit of butter and lemon juice, or roasting them for a little while in the oven.
But did you know you can also blanch, boil, and steam them as well, for a more delicate eating experience? This goes particularly well with white blanched asparagus, which tend to have a more delicate flavor profile than the typical green or purple varieties.
If you’re growing purple asparagus, this type may be so tender and sweet that you can add it raw straight to salads! Give it a rinse and a quick chop, and you’re ready to go.
Furthermore, grilling and pan-searing the spears are great methods, too – bringing out more interesting flavors the more blackened they get on the outside.
Here’s a few ingredient combination ideas for excellent dishes straight from the garden, some of these picked from Karen Page and Andrew Dornenburg’s book The Flavor Bible, available on Amazon.
- Chicken (and chicken stock)
Veggies and Nuts:
- Mushrooms (like morels and porcini)
- Parmesan cheese
Herbs, Seasonings, and Condiments:
- Black pepper
- Sea salt
- Lemon juice
- Olive oil
- Truffle oil
- Hollandaise, mayonnaise, aioli, or romesco sauces
- Vinegar and vinaigrette
- White wine
As prefaced in asparagus’s fascinating history, the growing of this vegetable was not always for food.
In fact, some could argue that it has a longer history as a medicine than it does as a delicious delicacy!
Many are acquainted with the strong smell you might experience during a bathroom trip after eating it – and this occurrence could have sparked its use as a diuretic and urinary medicine: to lower blood pressure, prevent heart disease, and help with kidney stones back in old days.
The shape of the spears was also an inspiration for its use in sexual health, especially for men in improving fertility and performance while reducing impotence. However, it had applications to female health, too.
A close relative to the common edible asparagus, shatavari (Asparagus racemosus), is an Ayurvedic remedy of both today and the past that’s used for many female reproductive imbalances: PMS, irregular periods, menopause, and more.
Interestingly, today there are studies supporting a lot of these classical uses.
One study in the past decade confirmed that consumption of the vegetable increases production of androgens, thus making it helpful for male sexual health – while also noting effects against cancer and cholesterol. Other more recent research pointed out notable kidney effects in line with traditional use.
Plus, according to NutritionData.com, they’re high in fiber, iron, calcium, manganese, vitamins A, C, and B vitamins (including folate), and especially vitamin K – making it a healthy veggie no matter what!
The Taste of Spring
Have you grown enough annual veggies, and think you’re ready to tackle asparagus next? After reading this comprehensive guide, I’d bet you are!
If you want to tend to, eat, and enjoy a healthy perennial food source that will come back again and again for years, this is the one to try – and if you do it right, it will become a beautiful, delicious, and semi-permanent addition to your garden or yard.
Ordering crowns and planting them is quite an easy task. With only a few important management tips to follow, the most you really have to do is harvest them regularly when the time comes – and once harvest season is over, just sit back and watch their statuesque fronds billow and grow, collecting energy for more spears next year.
Of course, watch out for the few bugs and diseases that can plague your patch. Vigilance is important when cultivating these succulent spears, but knowing what to look for isn’t all that hard, once you read up on what to watch out for.
Are you ready to plant asparagus? What are your personal experiences with growing, tending, and eating this delicious produce? We hope to hear from you – and please feel free to comment below!
This post is not intended to diagnose, treat, or cure any ailments and should not be mistaken for medical advice. Before changing your diet, talk to your doctor or other medical health professional.
Asparagus: Plant Care and Collection of Varieties
A classic spring treat, asparagus is a perennial that will produce tender spears every spring for many years.
Asparagus is grown from 1-year-old plants or “crowns,” which are planted in early spring as soon as the soil can be worked. Asparagus plants take three growing seasons to reach full production, although light harvesting can begin in the second year. Once established, an asparagus planting will provide abundant harvests for fifteen to twenty-five years. Allow ten to twenty plants per person (15 to 30 feet of row).
Choosing a site to grow asparagus
Select a well-drained site in at least part sun; full sun is not necessary. Asparagus will thrive in slightly acid soil (pH of about 6.5), but will tolerate alkaline conditions up to 9.0.
Eliminate all weeds by repeated tilling. Loosen the soil to a depth of 12 to 15 inches, then mix in a 2- to 4-inch layer of compost. Prepare the bed by digging trenches 4 feet apart. The trenches should be 12 inches wide and 6 to 12 inches deep. Soak the crowns briefly in lukewarm water before planting. Draw a hoe along each side of the prepared trench to form a mound in the center running the length of the trench. Set the crowns 18 inches apart on the mounds in the trench, draping the roots over the sides. Cover the crowns with a mix of one part compost to three parts topsoil, burying the crowns 2 inches deep. Water the bed thoroughly. After about a month, once shoots have appeared, carefully add more soil to the trench.
First year: Weed the beds frequently, taking care not to disturb roots. Periodically add more topsoil/compost around the emerging shoots until the trench is filled. Then spread a 4- to 8-inch layer of mulch, such as hay or leaves, around the base of the plants. Water regularly. Do not harvest any spears the first year. Cut down dead foliage in late fall and side-dress with compost.
Second year: Cultivate lightly by hand until the new spears are several inches tall. Keep the bed thickly mulched. Side-dress with compost in the spring and early fall. Cut down dead ferns in late fall. You may harvest very lightly the second year.
Third year and beyond: Maintain as for the second year, and begin harvesting.
How to harvest asparagus
Plants started from crowns can be harvested lightly in the spring of the second year. Begin harvesting in earnest the third year. Harvest only those spears that are thicker than a pencil. Cut off the spears at or just above ground level when they are 6 to 8 inches tall.
Asparagus is easy to grow and really doesn’t need anything special except a place where you can grow it for many years because it is a perennial vegetable that can thrive in the home garden for 15 years or more when well cared for. Asparagus plants should grow for at least 1 season in the garden before they are harvested. (Our 2 year crowns, available only in the fall, will be ready to harvest the next spring!)
Asparagus is most productive on deep, well-drained, sandy loam soil, but it will do well on other soils if it has good drainage. Many people grow it in large raised beds where it will thrive in nice soft soil with lots of mulching every year. The crown itself (the bud type thing at the top of the long spaghetti leg roots) is what will sprout the asparagus spears. Asparagus crowns planted close together will produce smaller, thinner spears and spacing them further apart will produce larger spears. Mulching well will keep the flavor sweeter and milder.
The First Growing Season
Asparagus should be planted in the early spring or in the fall when temperatures are cooler. Before planting, add compost and organic fertilizer to amend the soil. If pH is below 6.0, lime should be added to correct pH. Dig a V-shaped furrow, 6 inches deep. Plant crowns with the buds up in the bottom of the furrow, and cover them with 1 – 3 inches of soil. Space the crowns 12 to 16 inches apart within the row. Allow at least 3 feet between the asparagus rows or the next closest vegetable crop.
As the asparagus begins to grow, gradually fill in the furrow with soil. (Be careful not to cover any of the asparagus foliage.) The furrows should be filled to ground level by the end of the first growing season. Add organic fertilizer (about 1/4 cup per plant of granular) spreading the fertilizer on each side of the asparagus and cultivate it lightly into the soil. Good soil moisture is important during the first growing season. Irrigate or water your asparagus enough to wet the soil 8 inches deep every week.
The Second Growing Season
DO NOT harvest the asparagus spears that grow from 1 year crowns during their first season. Allow all of them to grow into brush which looks like dill or a ferny bush. Late in the fall of the first growing season, after the brush has turned completely brown, remove the brush (old stalks) and any weeds. (Note, in the fall, we have 2 year old crowns of Mary Washington asparagus that can be harvested in Spring of the following year.)
Early next spring, sprinkle some lime as needed to maintain the proper soil pH. (about 1 lb for a 10 X 10 bed) Add compost and organic fertilizer again. Thorough watering (1-2 inches of water) slowly applied every two weeks during dry weather is sufficient. Remove the brush each succeeding fall after it has turned brown.
Each succeeding spring, before the asparagus emerges, add lime if needed and add compost and organic fertilizer. Rake the fertilizer and lime into the soil gently, 1 to 2 inches deep. Take care not to damage the asparagus crowns.
Use a knife to harvest spears. Use one hand to hold the top of the spear you are harvesting. Cut the spear off about one inch below the soil line. Be careful not to cut too deep – it will damage the asparagus crown.
Harvest all the spears that come up during the harvest season. A good general rule for length of harvest season is the 2-4-6 week sequence. Harvest for 2 weeks the second year the plants are in the garden, 4 weeks the third year, and 6 weeks the fourth and all following years. Each succeeding fall, remove any brush after it has turned brown.
If you harvest asparagus that will be eaten later, wash the spears and place the cut ends in about 2 inches of water. Like fresh flowers, they will keep in the refrigerator for several days.remove the brush (old stalks) and any weeds.
Asparagus in autumn? Meet the man behind its extended season
John Chinn in his fields with his sons, Henry (left) and Chris Photo: Marsha Arnold
A brief stopover at Lintridge Farm near Ledbury, part of the Chinn fiefdom, is to be immediately immersed in asparagus in all its guises. Here Chinn runs 50 acres of tunnels, 220 acres of mini-tunnels and some open field, all dedicated to growing or trialling different varieties of green, purple and white asparagus. He meets me in a mud-spattered 4×4, nipping round to the boot to produce a cafetière of fresh coffee and a picnic basket.
‘The Romans used to send runners to take the asparagus up to the Alps to store it in ice so they could have it fresh later in the year’ John Chinn
Thus set up for a lengthy seminar, I learn that asparagus is a member of the lily family and that a single plant can last for up to 20 years; that seed is set in the spring and a year later the root and crown of the embryonic plant is dug up and sold to the grower – in this case, Chinn – who then plants it to harvest the following spring, although, in general, you have to wait for four years to get the full harvest, during which time the plant will have grown 8kg of roots up to 5ft deep.
That’s one reason asparagus needs such deep ridges of preferably free-draining sandy soil to grow successfully – the crowns need enough soil to push up against.
‘The traditional asparagus harvest takes place between St George’s Day and Midsummer Day,’ Chinn says, ‘but we’re extending this dramatically by growing cold-resistant varieties of asparagus in polytunnels. That means we can heat the soil as well as the polytunnels so that we can manipulate growth to harvest, in small amounts, as early as mid-February and then much later into the autumn.
‘It’s not a new thing,’ he adds, ‘the Romans used to send runners to take the asparagus up to the Alps to store it in ice so they could have it fresh later in the year.’
Chinn is a fan of the polytunnel – in them he can grow roughly 10,000 asparagus plants to the acre, each producing about 24-30 spears across a 40-day harvesting period. The plant grows spears every other day, but in May, assuming the temperature is right, can produce up to seven to eight spears a day.
Chinn’s newly harvested crop Photo: Marsha Arnold
Over a season Chinn can average roughly one ton of asparagus per acre. At the end of harvesting, you need to leave at least eight shoots on each plant to grow into a fern in which the plant stores energy for the following season. ‘This spring was too chilly,’ Chinn says, ‘but it warmed up in time for a normal harvest in the early summer.
‘Asparagus can grow 2cm an hour, so you can lean a stick against a spear, go away and come back later to see how much it’s shot up… It’s fascinating stuff.’
To produce asparagus later in the season, Chinn uses ‘reverse season’ growth, meaning that rather than harvest in the spring, he lets the plant fern from March to August, chops them down, ready to spear from the beginning of September until the end of October – thus producing a late crop.
Asparagus is labour-intensive and has to be harvested by hand. Chinn employs 1,200 or so people over the year, which rises to 2,000 for the asparagus season proper. ‘That doubles the population of the village.’ At this point the season is just getting under way.
‘We spend a lot of time pulling polythene on and off the tunnels to start picking,’ Chinn remarks as we pass a group of workers flipping off the polythene into the air like a field of experimental-theatre actors creating waves. The resulting exposed ridge of red Herefordshire earth is pierced with individual spears of asparagus growing out of it, like a large stubbly leg.
Disappointingly for Chinn, the rate of asparagus consumption per head in the UK lags far behind that of Germany and Holland. We only manage a paltry 140g of asparagus each a year. In Germany they get through 1.8kg each and they’re much keener on white asparagus – another passion of Chinn’s.
Photo: Marsha Arnold
In 2010, he trialled some white asparagus, which he sold through M&S in Oxford Street, but ‘it didn’t go at all well’. He tried again this year, but the British public remains strangely resistant.
Rabbits, on the other hand, absolutely love asparagus, especially the purple variety – you can almost hear them crunching away as we survey the glorious Herefordshire landscape. ‘Slugs and rabbits both,’ Chinn says sadly. ‘The footpaths over this land were walked by Rupert Brooke,’ he adds.
‘They didn’t plough this farm, even during the war, because the ministry thought the soil wasn’t good enough – they could have been feeding the population on asparagus…’ and doubling it too, if you believe in asparagus’s legendary aphrodisiacal powers. The poetic shade of Brooke means that requests for more polytunnels have been turned down. Chinn is philosophical about this, and is now expanding his asparagus operation in Norfolk.
Here in Herefordshire, we repair to Chinn’s house where his wife Gaye has devised a series of asparagus dishes accompanied by a Chinn sideline – English sparkling wine grown on his nearby Castle Brook Vineyard, where the Romans also planted vines.
He produces 10,000-20,000 bottles a year and, once you’ve got over the name, Chin Chin, it turns out to be pretty good – certainly a worthy companion to Mrs Chinn’s stir-fried asparagus with ginger and garlic, asparagus topped with a lemon and parmesan breadcrumb crust, and an excellent, if surprising, asparagus and cheese cake.
Reverse season asparagus: tips, £3 for 100g, spears £3 for 180g, extra fine, £3 for 110g, exclusively in Marks & Spencer stores this month
Asparagus recipes for autumn
The flavour of the asparagus shines through in this light mint dressing Photo: REX FEATURES
Fresh asparagus salad with crumbled feta
A citrussy dressing completes this bright combination of greens, leaves and feta
Wye Valley asparagus and cheese bake
A golden pine-nut topping adds crunch to this simple bake Photo: Marsha Arnold
Crispy prosciutto asparagus tips
Dip these warm spears into garlic mayonnaise or hollandaise Photo: Marsha Arnold
A delicious side side or tempting starter Photo: Marsha Arnold
Stir-fried asparagus with ginger and garlic
Team with grilled meat or fish Photo: Marsha Arnold