- Planting Bare Root Rhubarb – Learn When To Plant Dormant Rhubarb Roots
- What is Bare Root Rhubarb?
- How to Plant Bare Root Rhubarb
- Rhubarb Plants -How to Plant Rhubarb Plants /Crowns / Roots
- Instructions for How to Plant Rhubarb
- Diagram of How to Plant Rhubarb
- Tips for Growing Rhubarb
- How to Grow Rhubarb
- Which variety to choose
- Should you grow rhubarb from seed?
- When to plant rhubarb
- Where should you grow rhubarb?
- How do you plant rhubarb?
- Can you grow rhubarb in a container?
- How do you force rhubarb?
- Any seasonal advice for growing rhubarb?
- How do you harvest rhubarb?
- Any problems to watch out for?
- Growing Rhubarb
- Climate and Growing Region
- Planting and Spacing
- General Growing Information
- Do I need to thin my overgrown rhubarb?
Planting Bare Root Rhubarb – Learn When To Plant Dormant Rhubarb Roots
Rhubarb is often acquired from a neighbor or friend who is dividing a large plant, but bare root rhubarb plants are another popular option for propagation. Of course, you can plant seeds or buy potted rhubarb plants as well, but there is a difference between planting bare root rhubarb and the others. What’s bare root rhubarb? The following article contains information on how and when to plant dormant rhubarb roots.
What is Bare Root Rhubarb?
Bare root plants are dormant perennial plants that have been dug up, the dirt brushed off and then wrapped in damp sphagnum moss or nestled in sawdust to keep them moist. The advantage to bare root plants is that they are usually less expensive than potted perennials and are often easier to deal with than container grown plants.
Bare root rhubarb plants look like woody, dried roots and may sometimes arrive dusted with a powder to keep the root from molding.
How to Plant Bare Root Rhubarb
Most bare root plants available, such as rhubarb or asparagus, are planted during the cool dormant times of the year. Rhubarb is shipped out when it is dormant to reduce the risk of transplant shock and so it can be planted both in the fall and in the spring in most regions.
Before planting your bare root rhubarb, choose a sunny location with at least 6 hours of full sun and remove any weeds. Rhubarb thrives in fertile, well-draining soil with a pH of between 5.5 and 7.0. If planting more than one bare root rhubarb, allow at least 3 feet (.9 m.) between plantings.
Dig a hole that is about a foot wide by a foot deep (30 cm. x 30 cm.). Loosen the soil at the bottom and sides of the hole so the roots can spread more easily. At this point, if you want to amend the soil a bit, now is the time to do so. Add well-rotted or dry manure and compost along with the topsoil that was removed from the hole.
Back fill the hole a bit and position the bare root rhubarb plant so that the crown, opposite of the root end, is 2-3 inches (5-7 cm.) below the soil surface. Tamp the soil down lightly over the newly planted rhubarb to remove any air pockets and then water in thoroughly.
Rhubarb Plants -How to Plant Rhubarb Plants /Crowns / Roots
If you have rhubarb plants and you are looking for information on how to plant them in your garden, you have come to the right place!
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Although it is possible to grow rhubarb from seed, rhubarb planting using root stock, or crowns, is the favoured method for growing rhubarb, especially in Northern climates.
The best time to plant rhubarb from root stock or crowns, (also referred to as “rhizomes”), is in early spring.
Once planted, it will thrive in the cooler spring temperatures and will really begin to grow once the soil temperature reaches above 40 ° F.
In Southern climates rhubarb plants do not thrive as well as in Northern climates, because it does not grow well in temperatures over 90° F.
In some tropical and sub-tropical areas however, it can be grown during the cooler season of those climates.
In the Northern climates, where rhubarb flourishes very well, it requires at least 4 – 8 hours of sunlight daily.
In the Southern climates, it is advisable to plant rhubarb where it will receive some afternoon shade. Rhubarb stalks will be more spindly in these climates.
See Also: Can Rhubarb Be Grown in the South?
Rhubarb grows well in almost any garden soil, although, like most plants, it does not like soggy soil. Ideally, the area where you are planning to plant rhubarb should have well-draining soil with compost or well-decayed manure worked into the soil.
The ideal pH level for growing rhubarb is about 5.5 to 6.5.
Many people ask if they can grow rhubarb plants in pots or containers on their patio or their balcony.
Although some people do have success growing rhubarb in this way, it is not a recommended method of rhubarb gardening.
To read more about planting rhubarb in pots,
GO to Container Gardening – Can Rhubarb be Grown in Containers?
Instructions for How to Plant Rhubarb
In your prepared garden, dig a small hole where you plan to plant the rhubarb.
Add water to the hole.
Carefully remove the plant from the pot in which you have purchased it, and set it inside the hole. Be sure the soil of the potted plant is moist enough so that when you gently pull at the plant, the soil remains around the crown/roots like a “ball”)
Plant with the top bud about 5 cm (2″) below soil level.
Fill in the area around the plant base with soil, while ensuring the plant is firmly set.
If you are planting more than one plant, space the plants about 75 cm. (30″) each way.
Diagram of How to Plant Rhubarb
How to Plant Rhubarb Plants or Roots
Careful planting of rhubarb will ensure a bountiful harvest of healthy rhubarb stalks.
Enjoy watching your rhubarb garden grow and grow — and you don’t have to replant or seed it every year!
A few years after you plant your first rhubarb plant, you will notice how quickly it “self propagates” and you will most likely have more rhubarb than you can use fresh.
Gardeners having too much rhubarb is a comment that I hear from time to time. Having too much rhubarb means you have lots to preserve for winter!
That’s when you freeze it, or can or dry it! I prefer to freeze my extra rhubarb because freezing rhubarb is extremely quick and easy!
Here below, (or use the navigation bars) are helpful links to information about growing rhubarb in the home garden.
CARING for Rhubarb
Rhubarb COMPANION Gardening
More COMPANION Plant Ideas
LINKS RELATED TO RHUBARB GARDENING
ORGANIC PESTICIDE RECIPES and Information
EASIEST Vegetable to GROW
WEED CONTROL Tips
WHERE to Grow Rhubarb
How to GET RID OF SLUGS
CONTAINER GARDENING – Can Rhubarb be Grown in Containers/Pots?
Yorkshire FORCED RHUBARB
TOP of How to Plant Rhubarb Plants
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Tips for Growing Rhubarb
Last Updated: May 29, 2015 | by Mike McGroarty
Rhubarb is one of those garden plants that folks either love or hate. Those who love rhubarb eagerly look forward to the first harvest of this perennial plant each spring so they can savor the tart flavor in a cherished dessert recipe. Growing rhubarb in your own garden is incredibly easy and this carefree plant will provide a family with an ample supply of edible stalks for many years.
For many of us, our first encounter with rhubarb was in Grandma’s garden. Well known for its delicious qualities, rhubarb was sometimes referred to as “pie plant” in days past. Grandma may have been growing rhubarb near her strawberry plants. Rhubarb and strawberries go very well together and conveniently, both fruits are harvested at about the same time each year.
Rhubarb, or Rheum x hybridum, grows well in climates that experience cold winters. Growing rhubarb in growing zones 9 and higher is futile, as this plant needs to experience cold weather before it will begin growing in the spring. When temperatures climb above 90 degrees Fahrenheit in the summer, rhubarb will wilt and stop growing.
To begin growing rhubarb, purchase healthy plants from a nursery or acquire a divided plant from a gardening friend. Rhubarb comes in varieties with either red or green stalks, and although the red varieties are often preferred for their lovely color, green varieties are often much more productive and are also more heat tolerant.
Rhubarb is a tough plant, but for the most success in growing rhubarb, choose and prepare the planting area carefully. Because rhubarb is a perennial that will return year after year for up to twenty years, it should be located where it will not need to be disturbed. Rhubarb prefers to grow in full sun but it will tolerate light shade. A growing rhubarb plant is fairly tolerant of acidic soil and it will grow in soils with a pH as low as 5.0, but it is happiest in soils with a pH between 6.0 and 6.8.
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Although you can begin growing rhubarb by planting it from seed, it will take much longer for the plants to become harvestable, and a seed-grown plant will not grow true to the parent plant. Even if the parent plant produced lovely red stems, its seeds may grow into plants that produce only green stems.
Well draining soil is also essential for growing rhubarb. If you have clay or compacted soil that does not drain well, it is advisable to plant rhubarb in a raised bed. Crown rot is one of the few problems to effect rhubarb, and poorly draining soils will encourage crown rot.
Begin growing rhubarb by planting it in early spring. If planting one rhubarb plant – enough to feed a family of four – dig a hole about two feet wide and just as deep. Mix the soil with an equal amount of compost or aged manure, then partially backfill the hole with this mixture. Set the crown and roots on the mounded soil mixture and continue filling the planting hole until the buds are an inch or two below the surface. Be careful to not pack the soil tightly around the buds. Once planted, water the plant well and continue to give the plant about an inch of water weekly. Once the new shoots begin to emerge, the plant can be mulched with compost or shredded leaves to help keep the roots cool and moist.
A single rhubarb plant can grow to be four feet wide and up to three feet tall, so give your growing rhubarb plant plenty of room. If you wish to plant more than one rhubarb plant, space them about three feet or more apart. If planting several rhubarb plants in rows, each row should also be three feet apart.
A growing rhubarb plant needs time to establish itself, so no stalks should be harvested the same year it is planted. The following year, if the plant is growing well, a few of the small stalks may be harvested if you have a strong hankering for a taste of rhubarb, but it isn’t until the plant’s third year that it can be harvested fully.
To harvest rhubarb, the entire plant can be cut down at once, or individual stalks may be harvested as needed. Stalks may either be cut with a knife at the soil line, or pull on them gently and the entire stalk will separate from the crown.
Always cut the leaves from the stalks as soon as the stalks are removed from the plant. Rhubarb contains oxalate, which is present in all parts of the plant but the highest concentrations of oxalate are in the leaves and roots. Poisoning will occur if leaves or roots are ingested, so only the stalks should be eaten.
If you are growing rhubarb in your garden, children should be made aware that they should never eat the large, attractive leaves of the rhubarb plant.
Rhubarb is harvested mainly over a 4-6 week period in the spring and early summer. Later in the summer, the plant will produce seed stalks, and once the plant puts out seed stalks it will stop producing the edible leaf stalks. The edible stalks have a shape like the letter D, but the seed stalks will be round and thick, and they will grow much taller than the edible stalks. The seed stalks can be removed from the plant as soon as they appear. Removing them will help the plant put more energy into growing bigger and better edible stalks.
Once planted, growing rhubarb is almost effortless. The large leaves shade out most weeds, and very few pests bother the plant. Occasionally slugs will feed on lower leaves, but removing those leaves will solve the problem as the slugs will not be able to reach higher-growing leaves.
In the fall or early winter, feed rhubarb by applying compost or composted manure around the plant, being careful to not cover the crowns. Alternately, apply a couple handfuls of 10-10-10 fertilizer around each plant in the early spring.
Growing rhubarb doesn’t have to be limited to those of us with a great deal of garden space. Rhubarb can also be grown in containers in a patio garden. The container should be at least 24 inches wide and just as deep, and it should provide ample drainage. For potting soil, use a 50/50 mixture of good quality potting soil and compost, or an equal mixture of potting soil and composted manure. Just like growing rhubarb in the ground, a container-grown rhubarb plant needs about an inch of water each week and should not be harvested until its third year.
With very little effort, you can enjoy growing this lovely old-fashioned harbinger of spring and will soon have enough to share with your rhubarb-loving friends too.
Questions? I do my best to answer all questions on my blog…
How to Grow Rhubarb
The ultimate guide to growing rhubarb in the UK
What could be better than rounding off your Sunday lunch with a piping hot bowl of rhubarb crumble? Or how about a delicious rhubarb pie, summer fool or homemade jam?
Rhubarb is an undemanding perennial that’s easy to grow and fantastically hardy. In fact, it actually needs a cold snap in order to produce the best crops.
A healthy rhubarb plant will remain productive for at least 10 years so it makes an excellent investment. During the first year, you’ll need to resist the temptation to harvest the stems. But from the second year, you can harvest your rhubarb from April to June. Here are some tips to help you grow your own.
Which variety to choose
Different varieties have different flavours, strengths, and qualities.
There are lots of different varieties of rhubarb to choose from. Here are some of our favourites – all of which are suitable for planting in autumn or spring.
- • ‘Champagne’: Reliable and easy to grow, this early variety is ideal for forcing to produce long, slender, pink-tinged stalks. Leave it unforced for a deeper, red-coloured stem.
- • ‘Victoria’: These greenish-pink stems have an excellent balance of sweetness and acidity. Once established, it will produce a heavy crop, year after year.
- • ‘Raspberry Red’: These have thick, deep red stalks with a superb sweet flavour that can be harvested early in the season, without the need for forcing.
- • ‘Giant Grooveless Crimson’: This compact rhubarb produces a bountiful supply of tall, uniform, fully coloured, bright red stems with a delicate acidic flavour.
- • ‘Thomson’s Terrifically Tasty’: These thick pink, flavoursome stalks (that taper to green) are produced from March through to mid-summer, a whole month earlier than other rhubarb plants!
- • ‘Delight’: An everbearing variety that crops over a long period with good disease resistance, this rhubarb plant has dark green and red stems with a lovely flavour.
- • ‘Fulton’s Strawberry Surprise’: These strong, vigorous plants produce eye-catching, vivid red stems with a well balanced acidity. It was voted best-flavoured rhubarb in the RHS Wisley trials.
- • ‘Glaskin’s Perpetual’: This easy to grow garden variety produces large, juicy stems that can be lightly harvested the following year, if started in heat during the winter.
Should you grow rhubarb from seed?
A rhubarb crown is a good option for beginners and green thumbs alike.
Like most crops, you can grow rhubarb from seed, but it’s much easier to plant crowns or budded pieces. They establish well, making them ideal for beginners, but even experienced gardeners will appreciate the grow boost.
Rhubarb crowns are established plants that are at least one year old. They will produce a crop in the first harvest season after planting, which is much sooner than rhubarb plants that are grown from seed.
Budded pieces, meanwhile, are a portion of an established crown. These can be cropped two years after planting.
When to plant rhubarb
Rhubarb crowns are best planted in autumn or spring.
Rhubarb crowns and budded pieces are best planted in autumn or spring, while the soil is warm and moist.
If you’ve grown your rhubarb in a pot, this can be planted out at any time of the year as long as the soil is not frozen, waterlogged or suffering from drought.
Where should you grow rhubarb?
Find a place you’re happy for rhubarb to grow for up to 10 years.
While undemanding, there are a few key things to keep in mind when selecting a place to plant rhubarb.
Firstly, rhubarb grows well in a sunny position with moist, well-drained soil, but it will tolerate semi-shade.
It doesn’t respond well to disturbance so the place you choose will need to be a permanent home – somewhere your plants can grow without interruption, from year to year. Take the time to properly prepare the right spot in your garden before you begin planting.
How do you plant rhubarb?
Take some time to properly prepare the area before you plant.
Prepare the ground by thoroughly weeding the area and digging in two bucketfuls per square metre/yard of well-rotted manure.
Once you’ve done that, spread out the roots and plant so the tip of the crown is just visible above the soil.
When planting rhubarb crowns or budded pieces, set them so that the top of the crown sits 3cm (1″) below soil level. If you’re gardening on a heavy, wet soil then plant them slightly higher, so that the top of the crown sits at ground level. This will help to prevent crown rot. Rhubarb plants can get quite large so allow a spacing of 75cm (30″) between them.
Can you grow rhubarb in a container?
A big, deep container is a good option for growing rhubarb.
Image: Rhubarb ‘Fulton’s Strawberry Surprise’
Rhubarb plants have big root systems so they do require a decent amount of space to grow. But if you use a container that holds a minimum of 40 litres of compost, you should be fine. In fact, you’ll most likely produce a decent crop.
A soil-based compost, such as John Innes No 3. mixed with plenty of well-rotted manure, is best for growing rhubarb in a container. To get started, why not try one of our 60 litre vegetable patio bags.
How do you force rhubarb?
Traditional forcing pots work, but so do dustbins and buckets.
Forcing rhubarb will yield an earlier crop – a useful option if you can’t wait until April for your first harvest. While clay or terracotta pots are traditional (and are specifically designed for this purpose), an upturned dustbin or a large bucket will work equally well.
In January, cover the crown with a layer of straw and then place your choice of large container over the crown to exclude the light. Forced rhubarb stems can be harvested around eight weeks after covering, which may be up to a month earlier than unforced crops.
However, try to avoid forcing the same rhubarb crown for two years in a row; this can weaken the plant. Our top tip? Grow several rhubarb plants at a time and force just one a year in rotation.
Any seasonal advice for growing rhubarb?
Rhubarb needs different things at different times of year.
Rhubarb plants are very low maintenance, but they will produce better crops if given a little extra care and attention according to the season.
- • Spring: Remove rhubarb flowers as they appear in order to direct the plants’ energy into growing tasty stems. A feed of general purpose fertiliser will also give them boost during this time.
- • Summer: Keep an eye on your rhubarb plants and water them during dry periods. You don’t want the soil to completely dry out. Rhubarb that’s grown in containers will need to be watered much more often in order to keep the compost moist.
- • Autumn: When the leaves die back naturally, simply cut back the old rhubarb stalks to leave the buds exposed. Apply a mulch of well-rotted manure around the crown of the plant; this will help to conserve moisture in the soil and keep the weeds down, as well as feeding the plants for the following growing season. But take care not to cover the crown as this may cause it to rot.
- • Winter: Every five or six years you’ll need to lift and divide the rhubarb crowns in order to maintain their vigour and ensure that the plants remain productive. Use a spade to lift each crown before splitting it into 3 or 4 pieces and replanting them separately. Each piece needs a healthy looking bud – this will become the growth point for next year’s new shoots.
How do you harvest rhubarb?
A little patience in the first year helps you harvest more later on.
During the first year, you need to resist the temptation to harvest the stems, in order to allow your rhubarb plants to become properly established. But your patience will pay off because, from the second year onwards, your rhubarb can be harvested from April to June, when the leaves have fully unfurled and the stems are 30cm long.
To harvest, pull each rhubarb stalk from the base of the stem and twist it away from the crown. It?’s important to only harvest a few stems at a time (never more than half of the available stems), as over-cropping will reduce the plant’s vigour.
The rhubarb plant will need time to build up energy reserves for next year’s crop, so make sure to finish harvesting by the end of July. Don’t worry if you find that you have more rhubarb than you can use; rhubarb freezes really well. Pickling and preserving is also a great way to extend the shelflife of your rhubarb.
A word of warning: only the stems of rhubarb are edible. The leaves contain oxalic acid, which is toxic if eaten. Simply trim the leaves away from the stems and add them to your compost heap.
Any problems to watch out for?
Slugs and other critters may find your rhubarb appealing.
Crown rot can be a problem when growing rhubarb. It’s caused by fungi or bacteria (either in the soil or water) and, once it spreads, the disease call kill the plant. The best thing to do is act quickly and cut away any affected areas of the plant. Don’t be afraid to cut into healthy plant tissue – it could save the whole plant.
You may find that slugs, snails and other garden critters feed on your tasty rhubarb. The bane of gardeners all over the world, you’ll probably have your own way of dealing with slugs, from eggshell barriers to biocontrols. Keep an eye on your plants and deal with any pests quickly.
Which slug-deterrents have worked best for you? Get in touch over on our Facebook page and let us know! In the meantime, happy growing!
Rhubarb is pretty easy and will reward you with many years of succulent stalks for 10 years or more. It’s a plant that looks beautiful in the garden with its huge leaves and bright red stems, an impressive looking crop for a first time grower! We stock 3 of our favourite varieties which can be easily ordered below:
Rhubarb Mix Pack
So, let’s get stuck in with the first step, where do I put it?
Site and Soil
The sunniest spot in the garden is the best but rhubarb will tolerate partial shade and still do well. Partial shade does not mean a corner of the garden that gets a couple of hours of sun in the morning, make sure you get 5 or 6 hours of direct sun a day. Be aware that your new rhubarb plant will be in the same position for 10 years meaning the soil around the plant can’t be dug over to avoid damaging the wide root system. When planning your planting position be aware that a medium sized rhubarb plant will be about 4 foot in diameter so make sure you have enough room!
Rhubarb will prefer a well drained soil so if you have a wet garden we recommend using raised beds. Dig over your soil 4 weeks before planting and remove as many stones as you can. Dig in plenty of organic matter as rhubarb won’t tolerate soil disturbance once it has become established. The reason for leaving 4 weeks between digging and planting is to give the soil and added organic matter time to settle. For very high quality bulk organic matter we recommend ‘Envirogrind’ natural soil improver sold in 1 tonne bags.
When to plant
You can grow rhubarb from seed but it takes much longer and can result in plants which aren’t true to the parent variety. It’s much easier to plant part of a divided rhubarb plant which are known as rhubarb crowns. The best time to put in Rhubarb crowns is late Autumn – early Winter. November and December are perfect for starting off your new plants.
How to plant
Make sure you get your Rhubarb plants from a reputable supplier (us!) to ensure they are disease free. Dig a hole in your prepared bed a little wider than your rhubarb crown. The crown should be planted so the tip of the plant is approx 2.5cm below the surface of the soil. Firm the surrounding soil in around the roots to ensure it’s well packed and no air pockets remain. If due to some extraordinary shift in Irish weather conditions the ground is dry water well to help the plant get established.
Spread a compost mulch around the plant but not directly above the growing tip where it will emerge in 4 weeks or so.
|Variety||Between Plants||Between Rows|
|Timperley Early||75 cm||75 cm|
|Victoria||1.2 m||1.2 m|
|Glaskins Perpetual||80 – 90 cm||1 m|
Rhubarb plants require very little care and will produce for you even if you just leave them alone and ignore them. With a little care and attention however they will produce much finer stalks and crop better than lonely plants.
When the season is over and the leaves have died down spread a layer of well rotted garden compost (If you don’t have any our ‘Envirogrind’ is perfect) around the plant ensuring it’s not touching the stems. If the Summer is dry (again, unlikely) give the plants an occasional soaking. Keep the area around the plant well weeded.
Cut off any flower heads which may appear in early Spring as the new rhubarb stalks emerge from the soil. Do this as soon as you can as if the flower head is left to grow and produce seed the plant will never recover to full strength.
Rhubarb suffers from very few pests and diseases with the only problem you may encounter being crown rot. Crown rot can be avoided by planting in well drained soil and avoiding burying the growing tips under compost. If you stick to the planting guidelines this is unlikely to be a problem.
It will be tempting to harvest some of the stalks in the first year. Don’t. You should leave the new plants for the first year without harvesting any stalks as this will weaken the plant. You want your rhubarb to establish a good healthy root system and it will need all its foliage to do this.
During the second season you can pick a few stems making sure you only pull two per plant at any one time and that at least 5 healthy stalks remain. From the third season onwards pull three or four stems at a time making sure you leave 3 or 4 on the plant. The rhubarb will produce stalks from May until July or August and should give you 2 or 3 pickings from each plant.
To pick, remove the largest stalks when the leaves have fully opened. Remove the stalks by pulling gently from the base of the plant while using a twisting motion. The leaves can be composted but please don’t eat them as they are high in oxalic acid and therefore poisonous.
Rhubarb can be forced by covering with a large container like a dustbin or large pot to exclude any light. The lack of light and the warming effect of the container will make the rhubarb grow faster meaning it’s ready for picking about a month before it’s normally ready. We tend to grow ‘Timperley Early’ as this gives a very early crop without the need for forcing but it is fun to do and some people will tell you the end result is sweeter.
Forcing should be started in January. Remove any dead leaves and debris from around the plant so the crown doesn’t rot. Make sure your covering excludes all light so plug and small holes or gaps. You can also add some dry straw around the crown for extra insulation if the weather is very cold. A dark coloured bucket will absorb more heat and will warm better.
The stalks should be ready for harvesting approx 8 weeks after covering or when the stalks push the bucket off.
Rhubarb is a cool season, perennial plant that is very winter hardy and resistant to drought. Its crop is produced from crowns consisting of fleshy rhizomes and buds. Following a season of growth the rhubarb crown becomes dormant and temperatures below 40 °F / 5 °C are required to stimulate bud break and subsequent growth. The first shoots to appear in the spring are edible petioles and leaves. These emerge sequentially as long as temperatures remain cool (below 90 °F / 32 °C). As temperatures increase, top growth is suppressed, even appearing dormant in periods of extreme heat. With declining temperatures in later summer, foliage growth resumes.
Climate and Growing Region
Rhubarb is a cool season, perennial crop. It requires temperatures below 40 °F / 5 °C to break dormancy and to stimulate spring growth and summer temperatures averaging less than 75 °F / 24 °C for vigorous vegetative growth. The Northern U.S. and Canada are well suited for rhubarb production. In the United states it grows best in the northern states from Maine south to Illinois and west to Washington state. Once planted, rhubarb plantings remain productive for 8 to 15 years.
In the United States, commercial production is concentrated in Washington (275 Acres), Oregon (200 Acres), and Michigan (200 Acres), with small commercial acreage in many northern states field and greenhouse forced production. A good commercial yield is 15 tons and an exceptional yield is about 18 tons. Red varieties usually yield about 50% of the green types; however, if the crop is harvested twice in one year, total yields will increase about 50%.
Rhubarb can not be very successfully grown in the southern regions of the United States, although there are exceptions. Rhubarb is a popular garden vegetable in northern areas of the United States but unfortunately will not do well in hot, dry summers of the south. If it survives the heat it will not grow well will produce only thin leaf stalks which are spindly and lack color. Rhubarb will wilt very quickly on hot days (over 90 °F). There has been mention of an unknown variety of rhubarb with large green petioles that thrives in the Panhandle north of Amarillo (Texas).
Rhubarb tolerates most soils but grows best on fertile, well-drained soils that are high in organic matter. A clean planting site is essential for the cultivation of rhubarb since no herbicides are registered for use on rhubarb. Small areas of perennial weeds can quickly build up to serious proportions. To prevent this, all perennial weeds should be killed the year before planting. The fields should be cultivated in the spring and after cutting, and hand hoeing may also be necessary. Rhubarb is relatively free of insect and disease problems.
Rhubarb is rather tolerant of soil acidity but does best in slightly to moderately acid soil. The crop can tolerate soil pH as low as 5.0; however, maximum yields are attained at a pH of 6.0 to 6.8. Liberal quantities of fertilizer are needed.
Rhubarb responds well to fertilizers. The quality of the crop harvested depends to a large extent on the care and fertilization received. Commercial growing requires about 1500 pounds of 10-10-10 per acre before planting. Home gardeners should give each plant 1 cup (about 2 handful’s) of 10-10-10 fertilizer each spring, applied in a circle around the plant when growth starts. Fertilize each year and cultivate shallowly as often as necessary to remove weeds.
Manure is an extremely valuable source of organic matter as it helps to conserve moisture, preserves the soil structure, and makes nutrients readily available. Fifteen tons of manure should be applied per acre before planting for commercial growing or one to two shovels per plant for home gardeners. An application of composted manure or leaves is beneficial in late fall and early winter, but do not cover the crowns as this may promote rotting. Fresh manure should not be used as this will burn the tender rhubarb plants.
Adding Manure to rhubarb plant
Planting and Spacing
Plant rhubarb roots in early spring. Planting seeds is not recommended as it may take too long for the plants to become established, and the seedlings would not come true to color and size, if that is important to you.
Space rhubarb roots 24 to 48 inches (60-120 cm) apart in rows 3 to 4 feet (1 m) apart for commercial growing. These distances can be decreased to 36 inches for plants in rows and rows for smaller gardens (non commercial). Much smaller than this will seriously crowd the plants and result in a diminished crop and increase the likelihood of spreading disease. A 2-3 year old plant, the Victoria variety can be 4 feet (1.25 meter) in diameter and 3 feet (1 meter) tall. Plant the roots with the crown bud 2 inches (5 cm) below the surface of the soil. The hole for the crown should be dug extra large and composted manure, peat moss or dairy organic should be mixed with the soil to be placed around the roots. Firm the soil around the roots but keep it loose over the buds. Water the crowns after planting. Give the plant 1/4 cup of 5-10-10 worked in to the top 10 inches of soil at planting time. Good garden drainage is essential in growing rhubarb. For home gardeners, planting in raised beds helps ensure against rotting of the crowns. Crowns will have a longevity of many years, but because of diseases and insects, it is Normal to reset a bed after 4-5 years.
General Growing Information
Rhubarb responds to good care and watering. Remove the flower stalks as they are seen. During the first year of planting, the stalks should not be picked, since food from the leaves is needed to nourish the roots for the next year’s growth. One light picking may be taken during the year following planting if the plants are vigorous, and beginning the second year following planting, the entire plant may be harvested. When harvesting rhubarb, the first step is to cut the stalks at the soil line or simply pull them out individually. All of the stalks of a plant may be harvested at one time, or pulled out selectively over a 4-6 week period. After the stalks are cut, the leaves may be removed. For the home (small) gardener, rhubarb will tolerate a fair amount of neglect and still thrive, they are very tough plants.
The rhubarb season (in the United States) runs from April to September, although it can be grown forced (see Forcing in winter) which accounts for its availability early in the year when other crops are scarce. Early forced rhubarb has a distinctive bright pink color and delicate flavor. Outdoor rhubarb is a little darker in color.
Refrain from harvesting rhubarb the first year after planting. Each plant needs time to build up food reserves in the root to produce thick, robust stems.
Established rhubarb plants can be coaxed into early outdoor production by covering plants with clear plastic in the early spring, before the crown starts to grow. As growth starts, cut 1/4 inch ventilation holes in the plastic. As leaves get larger, cut the plastic to keep the leaves free.
Rhubarb hit by a frost or freeze can still be eaten provided the stalks are still firm and upright. Leaf injury may be noticeable with some brown or black discoloration on the edges. If the stems appear soft and mushy, do not eat them. Severe cold injury may cause the oxalic acid crystals in the leaves to migrate to the stalks increasing the likelihood of poisoning problems. If in doubt about the safety of eating the stalks, don’t. Cut those stalks off and compost them. Allow new stalks to develop before eating, or if it is the end of the growing season, try forcing some rhubarb indoors (see Forcing in winter).
How do I prepare my rhubarb plants for winter
Rhubarb needs cold to trigger spring growth. Rhubarb tolerates very cold (-20 F) very well. Collect the last few stalks after the first hard frost and throw them on the compost pile. Then spread a layer (2-3″) or compost (or leaves or hay) to prevent winter winds from drying out your roots. You don’t need to do much.
Do I need to thin my overgrown rhubarb?
Established clumps will have to be trimmed every 4 to 5 years or when the stalks get small and spindly or when the crown is visibly crowded. This will help the plant to keep growing nice thick stems. This is done by digging around and trimming the crown down to 4 or 5 buds. You can also use this opportunity to divide your plant into more plants. You may encounter is rot in the crowns from excessive water in the crown area. If so, destroy these plants.