Hardy rosemary zone 6

Growing Rosemary in Zone 5

According to the hardiness maps we are too far north (zone 5) to grow rosemary as a perennial. So I thought putting a rose cone over it might help it make it through the winter. Is that a good idea? I put it on after we had some pretty cold weather, and when I put it on, it still looked green. What do you think?

Rosemary is generally hardy in zones 8 and 9. A few cultivars like Arp and Hill Hardy will survive in zone 7 and a few gardeners report success in zone 6b. Check out the National Arboretum located in zone 7 for more details on their rosemary hardiness study. You may chuckle when they talk about their challenging winter which is much milder than those gardening in zones 2 through 5. You have nothing to lose by trying the rose cone. You may need to vent the cone on sunny days when the temperatures inside the cone can cook the plant. Be sure to remove the cone when spring temperatures start hovering above freezing. Next fall consider bringing a plant indoors. Though challenging to over winter inside you have a better chance for success and even the dried dead plant is fragrant.

Herbs to Grow in Manitoba (Zone 3A)
Answered by: Richters Staff
Question from: Gordon Ogilvie
Posted: Before April 1998
I live in South Central Manitoba and I am an amateur gardener. I would like to grow herbs but I don’t know which herb varieties would grow best in a short season. We are Hardiness zone 3A. We normally plant our garden during the long weekend in May because soil temperature are suitable for planting at that time. We also have a risk of frost by mid- september. I would like to know which herb varieties are suitable for our conditions. Can you please help me?
Increasingly herb books are listing zone ratings. The best is Deni Bown’s “Encyclopedia of Herbs & Their Uses” which is an excellent all-round reference book that any serious herb gardener should get. Richters carries this book, as well as others that list zone ratings. You can quickly see from the zone ratings which herbs are likely to do well in your area.
You may find that not many of your favourite herbs are rated zone 3 or lower. That does not mean you cannot grow those plants; zone ratings are only a guide and in fact many plants rated for higher zones will grow in your area successfully.
This point needs to be emphasized. First, because most herbs have not been subjected to exhaustive hardiness trials, most zone ratings are approximations or even guesswork. Second, local conditions have a profound effect on hardiness. French tarragon will be perfectly hardy in a sandy, well-drained soil in zone 5, but in heavy, wet clay, it cannot survive in even zones 6 or 7. Third, with protection such as winter mulching you can often “push” plants to grow in a colder zone. Fourth, even if a plant does not survive the winter in your area you can still grow them as annuals, or bring them indoors over winter. What matters is whether or not you get enough growth to get a harvest.
Some suggestions:
Lemon balm: perennial, zones 4-9. May be pushed to zone 3 *if* soil drains well and *if* protected with a winter mulch.
Basil: most are annuals; all should be planted after the ground is warm: in your area that may mean early June.
Chives: perennial, zones 3-9.
Dill: annuals; sow directly in the garden in late May or transplant peat pot seedboxes (without disturbing the roots – very important!).
Lovage: perennial, listed as zones 5-8, but we believe that it will survive colder zones, possibly zone 3 with protection.
Sweet marjoram: a tender perennial (zones 9-10) that is normally grown as an annual.
Greek oregano: perennial, zones 5-9. Probably won’t survive zone 3 even with protection and excellent drainage, but it can be grown quite successfully as an annual.
Rosemary: tender perennial, zones 8-10. Can be grown as an annual or dug up and overwintered indoors.
Garden sage: perennial, zones 5-8. Like oregano, probably will not survive zone 3 but can be grown as an annual.
Savory: the summer type is annual and the winter type is perennial. Winter savory is rated zones 5-8, and is probably matures too slowly to grow as an annual. Summer savory is better as it grows more quickly and will yield a harvest.
Sorrel: perennial, zones 4-8. Probably will survive zone 3 with protection and good drainage.
French tarragon: perennial, zones 4-7. Needs protection and excellent soil drainage to survive. May only work as an annual.
English thyme: perennial, zones 4-8. Same as tarragon.

Quick Guide to Growing Rosemary

  • Plant rosemary in spring once all chances of frost have passed. This delightful herb is an all-star in the kitchen and is a great option for raised garden beds, containers, and in-ground gardens.
  • Space rosemary plants 2 to 3 feet apart in an area with abundant sunlight and rich, well-drained soil with a pH of 6.0 to 7.0.
  • Before planting, set your garden up for success by mixing in several inches of aged compost or other rich organic matter into your native soil. For container growing, consider a premium bagged potting mix.
  • Promote spectacular growth by feeding rosemary regularly with a water-soluble plant food.
  • It’s important to water regularly but be sure to let the soil dry out between waterings.
  • Harvest rosemary stems by snipping them with sharp gardening shears. Harvest often once the plant is established, but avoid pruning more than one-third of the plant at a time.

Soil, Planting, and Care

Set out rosemary in spring, planting starter plants 2 to 3 feet apart; you can also plant in fall in zone 8 and south. Choose strong, vigorous Bonnie Plants® rosemary to get your garden off to a great start—after all, Bonnie has spent over a century helping home gardeners successfully grow their own food. Plants are slow growing at first, but pick up speed in their second year.

Rosemary prefers full sun and light, well-drained soil with a pH between 6 and 7. Improve your existing soil by adding a few inches of aged compost-enriched Miracle-Gro® Performance Organics™ All Purpose In-Ground Soil and mixing it in with the top layer. Potted rosemary needs a lighter-weight soil mix, so fill containers with Miracle-Gro® Performance Organics™ All Purpose Container Mix instead. Keep the soil uniformly moist, allowing it to dry out between waterings. Mulch your plants to keep roots moist in summer and insulated in winter, but take care to keep mulch away from the crown of the plant. In the spring, prune dead wood out of the plants.

For best growth, it’s not enough just to start with rich, nutritious soil. You’ll also want to feed rosemary regularly throughout the season with a plant food that feeds both your plants and the soil, like Miracle-Gro® Performance Organics™ All Purpose Plant Nutrition (following the directions on the label).

Zone 5 Rosemary Plants – Tips On Growing Rosemary In Zone 5

Rosemary is traditionally a warm climate plant, but agronomists have been busy developing cold hardy rosemary cultivars suitable for growing in cold northern climates. Keep in mind that even hardy rosemary plants benefit from ample winter protection, as temperatures in zone 5 may drop as low as -20 F. (-29 C.).

Selecting Zone 5 Rosemary Plants

The following list includes rosemary varieties for zone 5:

Alcalde (Rosemarinus officinalis ‘Alcalde Cold Hardy’) – This cold hardy rosemary is rated for zones 6 through 9, but it may survive the upper ranges of zone 5 with adequate protection. If you’re in doubt, plant Alcalde in a pot and bring it indoors in autumn. Alcalde is an upright plant with thick, olive-green foliage. The blooms, which appear from early summer to fall, are an attractive shade of pale blue.

Madeline Hill (Rosemarinus officinalis ‘Madeline Hill’) – Like Alcalde, Madeline Hill rosemary is officially hardy to zone 6, so be sure to provide plenty of winter protection if you want to try leaving the plant outdoors year round. Madeline Hill displays rich, green foliage and dainty, pale blue flowers. Madeline Hill is also known as Hill Hardy Rosemary.

Arp Rosemary (Rosemarinus officinalis ‘Arp’) – While Arp is a very cold hardy rosemary, it may struggle outdoors in zone 5. Winter protection is critical, but if you want to eliminate all doubt, bring the plant indoors for the winter. Arp rosemary, a tall variety that reaches heights of 36 to 48 inches, displays clear blue flowers in late spring and early summer.

Athens Blue Spire Rosemary (Rosemarinus officinalis ‘Blue Spires’) – Athens Blue Spire presents pale, gray-green foliage and lavender-blue flowers. Once again, even cold hardy rosemary such as Athens Blue Spire may struggle in zone 5, so give the plant plenty of protection.

The most important aspect of growing rosemary plants in cooler climates is to provide adequate winter care. These tips should help:

Cut the rosemary plant to within a couple of inches from the ground after the first hard frost.

Cover the remaining plant completely with 4 to 6 inches of mulch. (Remove most of the mulch when new growth appears in spring, leaving only about 2 inches in place.)

If you live in a very cold climate, consider covering the plant with extra protection such as a frost blanket to protect the plant from frost heaving.

Don’t overwater. Rosemary doesn’t like wet feet, and damp soil in winter places the plant at higher risk of damage.

If you choose to bring rosemary indoors during the winter, provide a brightly lit spot where temperatures remain about 63 to 65 F. (17-18 C.).

Tip for growing rosemary in cold climates: Take cuttings from your rosemary plant in spring, or after the flower has finished blooming in late summer. That way, you’ll replace plants that may be lost during the winter.

As the Mediterranean is the source of so much goodness on our dinner tables, it’s hardly a surprise that the region is also home to rosemary (Salvia rosmarinus), the pungent member of the mint family that adds the perfect flavor to many dishes.

While US gardeners who live in climates similar to that of the Mediterranean – one that’s warm and dry – are able to grow rosemary year-round, those in more northern climes may fear they are less fortunate.

But no!

Mother Nature has gifted our northern friends with a number of rosemary varieties that can withstand the chill and still reward with garden interest and palate pleasure.

And while there are no varieties that are rated to consistently withstand the brutal chills of -10°F to -20°F temperatures that can occur in Zone 5 and below, with planning and preparation, gardeners in Zones 5, 6, and 7 have fairly solid odds of overwintering their plants.

Best Cold Hardy Rosemary Varieties

  • Tips for Growing Rosemary in Cold Weather
  • Best Cold Tolerant Cultivars to Choose
    1. Alcalde
    2. Arp
    3. Athens Blue Spire
    4. Madalene Hill

Let’s learn more about rosemary varieties that – with a little TLC – will do well in cooler areas.

But first we’ll look at the best way to ensure success when growing rosemary in Zones 5-7.

If you’d like to learn all there is to know about rosemary, check out our complete growing guide.

Tips for Growing Rosemary in Cold Weather

Before you even install your rosemary plants in the garden, give the process some consideration.

Photo by Lorna Kring

The easiest way to ensure it survives the winter is to plant rosemary in a container, and overwinter it indoors.

If your potful of rosemary has gotten a bit unwieldy, as rosemary is wont to do, you can certainly give it a bit of a haircut before you bring it inside.

However, if your plant is already in the ground, and you’re thinking it might not make it through the winter chill, consider digging it up and replanting it in a container.

Before transplanting, you’ll want to trim it back.

Plan to do this in late August or early September, and why not prepare some grilled rosemary-garlic hamburgers the evening you do the trimming, so you can make use of all those flavorful cuttings.

Read our full guide to protecting rosemary plants in winter here.

Photo by Lorna Kring

If you’re set on a permanent outdoor planting, choose your site carefully. You’ll want a sunny, sheltered location, preferably near a building.

After the first frost, prune your plant to about 3 inches, and completely cover the plant and the growing area with a thick, 4 to 6-inch layer of mulch.

Learn more about mulching to protect crops in winter here.

Best Cold Tolerant Cultivars to Choose

Most important to ensure overwintering success, of course, is selecting a plant variety that is especially well-suited to withstand cold temperatures. We’ve curated a few options for you:

1. Alcalde

This variety was originally found growing in a northern New Mexico garden and was brought into cultivation by Charles Martin, an agronomist.

In its native habitat, it had withstood years of sub-zero winters at high elevations.

‘Alcalde’ produces pale blue flowers and wide, olive-green leaves.

This upright type grows up to 30-36 inches tall and 24-26 inches wide.

2. Arp

Considered the most cold-tolerant rosemary variety, ‘Arp’ can withstand temperatures down to -10°F. It grows up to four feet tall and about as wide.

‘Arp’

The slim leaves are gray-green and the flowers are bright blue. You can prune this upright plant regularly to create a denser form, or to create a topiary.

You can find the lemony-flavored ‘Arp’ variety available at Burpee.

3. Athens Blue Spire

Discovered in 1998 in a crop sown from a packet of commercial rosemary seeds by a horticulture researcher at the University of Georgia, this variety is still making its way to widespread availability.

The researcher culled it for its vigor, cold hardiness, branching, and upright growth habit – it grows to about three feet tall and two feet wide.

‘Athens Blue Spire’ will survive temperatures ranging down to -5°F to -10°F.

4. Madalene Hill (Hill’s Hardy)

Named for a well-known and beloved herb expert, this variety is sometimes misspelled ‘Madeline’ or called ‘Hill’s Hardy.’

‘Madalene Hill’

‘Madalene Hill’ grows 36-40 inches tall, with an irregular, upright habit.

It is hardy to 0°F. Bees love its nectar-rich, light blue springtime flowers. Its fragrant needles are dark green.

Find a live ‘Hill’s Hardy’ rosemary plant in a four-inch pot at Hirt’s Gardens via Amazon.

Safe Passage for a Tasty Plant

Rosemary’s distinctive flavor is so delicious that it’s no surprise gardeners in colder regions would be keen on overwintering their plants.

The keys to doing this are site selection, winter protection, and varietal selection. Choose a variety that is known to be cold hardy, and carefully place it where it will have the best chance against winter’s wrath.

Plants overwintered outdoors should be protected from the elements with lots of mulch.

Looking for other herbs to grow in your garden? Check out these articles:

  • How to Grow Winter Savory
  • Grow Common Sage, A Mediterranean Culinary Staple
  • How to Grow and Use Lemon Balm

79shares

  • Twitter
  • Pinterest79

Photos by Lorna Kring © Ask the Experts, LLC. ALL RIGHTS RESERVED. See our TOS for more details. Originally published on January 1, 2020. Last updated: January 19, 2020 at 14:24 pm. Product photos via Burpee and Hirt’s Gardens. Uncredited photos: . With additional writing and editing by Clare Groom.

About Gretchen Heber

A former garden editor for a daily newspaper in Austin, Texas, Gretchen Heber goes through entirely too many pruners and garden gloves in a year’s time. She’s never met a succulent she didn’t like and gets really irritated every 3-4 years when Austin actually has a freeze cold enough to kill them. To Gretchen, nothing is more rewarding than a quick dash to the garden to pluck herbs to season the evening meal. And it’s definitely time for a happy dance when she’s able to beat the squirrels to the peaches, figs, or loquats.

Growing Rosemary in Winter

submitted by Sarah Browning, UNL Extension Educator

email this page to a friend

Rosemary, Rosmarinus officinalis, combines ornamental beauty and the usefulness of a culinary herb in one attractive plant. Rosemary grows as a woody, evergreen shrub, and in its native Mediterranean region they can easily grow to a height of 4-6 feet. However, they seldom reach that height in Nebraska gardens.

The plants have slender, needle-like foliage, with either a dark green or gray-green coloration. The foliage is fragrant, and plants produce flowers in spring and summer that are light blue, pink, or white.

Winter Protection

However rosemary is a very tender perennial herb, and so is usually grown as an annual in Nebraska. Under normal garden conditions plants are hardy to Zone 7, and possibly to Zone 6 with winter protection. Occasionally in eastern Nebraska, hardiness zone 5, gardeners can find just the right spot that provides extra warmth in winter, protection from wind, and well-drained winter soil conditions that will allow rosemary to survive if they are given extra winter protection.

Their roots are more cold-hardy then the top-growth, so protection must be provided for the branches and foliage to survive. However, the biggest threat to winter survival is wet, poorly drained winter soil.

In the summer garden, rosemary prefers a sunny, sheltered location with very well-drained, dry, and almost gravelly, slightly acidic soil. For their best winter survival, rosemary should be planted close to your house on the south or west side so that plants benefit from retained and reflected winter warmth.

Make sure plants are protected from strong winter winds. This can be done through the use of rose cones placed over the plants in late November. Also mulch the roots with 5-6 inches of wood chips to provide additional root protection.

‘Arp’ is a common cultivar, originated by Madalene Hill from Arp, Texas, and is one of the most winter hardy types (Zone 6). It has light blue flowers on upright 3′ tall plants.

Rosemary As A Houseplant

If you don’t want to take the chance that your rosemary may not survive outside, then plants can also be grown as houseplants. Simply dig up your plants and repot them into containers for growth inside during winter. Remember to use a potting soil that contains perlite and/or vermiculite to improve drainage. Or create your own potting soil by mixing 2 parts peat-based soil with 1 part clean sand.

Provide plants with a bright, sunny window during winter. Normal indoor temperatures are fine during winter, but rosemary would also be happy in cooler conditions 55-50 F if that is available. Water as needed to keep plants evenly moist to slightly dry.

Another option, if you don’t have room inside for rosemary in containers, is to harvest long stems or whole plants before frost and hang them upside-down in bunches in a warm, well-ventilated location to dry. Once dried, strip leaves from the stems and store them in tightly covered jars in a dark, cool location. If moisture condenses inside the jars, more drying is needed.

Leave a Reply

Your email address will not be published. Required fields are marked *