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.The easiest way to ensure it survives the winter is to plant rosemary in a container, and overwinter it indoors.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.Alcalde This variety was originally found growing in a northern New Mexico garden and was brought into cultivation by Charles Martin, an agronomist.‘Alcalde’ produces pale blue flowers and wide, olive-green leaves.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.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.Product photos via Burpee and Hirt’s Gardens. .
The Secret to Keeping Rosemary Alive Indoors
Growing rosemary indoors is a little tricky.Best to keep it in a pot and move it inside for the winter.If you want to keep the plant a certain size, root pruning will help you keep it happy in the same size pot, year after year (read below).Make sure the pot has a drainage hole and a drainage pan, and use a well-drained potting soil.Rosemary is called an “upside-down plant” because it likes dry roots and prefers to absorb moisture from the air through its foliage.How to Water Rosemary.How you water this herb inside is crucial, however.Indoors, water the soil every two weeks (if the soil is dry), but always keep water in the drainage pan with the rocks in it.Fertilizing Rosemary Indoors.Sizing Rosemary to the Pot.Each spring, evaluate your rosemary’s size, repot it in new soil, and prune the roots as needed.After each season, your plant will have extracted all of the nutrients available in the potted soil mix, so in the spring you’ll want to repot rosemary with new potting soil.This is a good time to check the roots and root prune if necessary.Root Pruning Container-Grown Rosemary.If your rosemary has outgrown its pot, you can prune the roots to keep your plant growing in the same pot.Have you kept your rosemary plant alive indoors? .
This year, we have two we keep as ornamentals and allow to bloom, and two for culinary use in containers, because I have a hoarder-like fear of running out of rosemary.Why not have rosemary all year long?Here are a few ways to push the zone a bit on rosemary, and my tip for keeping rosemary (and lavender) healthy through winter.I have one container on the southwest side of my patio for easy access and another against a southern wall that gets full sun all day in the winter.Harvest some rosemary for culinary use well before the first frost so that the plant is healthy and not blooming.Carefully brush as much snow off of the plant as you can, especially over the center, main branches.This is not a ton of snow, but is enough that the slow dripping from melting could damage some of the branches or roots of this rosemary plant. .
How to Protect Rosemary Plants in the Winter
If you live on the edge of rosemary’s winter survival zone, in Zone 8 or 9, you’ll need to provide extra protection for your plants if you want them to overwinter outdoors.One option is to cover them with floating row covers.Another option is to prune and mulch your plants right before temperatures dip below freezing.Mulch also protects the soil from cycles of freezing and thawing, helping to keep soil temperatures stable.You can read more about mulching to protect plants in winter here.If you live in Zone 7 or below and your plants are growing in the ground outside, you’ll need to pot them up and take them indoors away from the cold.You’ll need to dig up your plants before the first frost has a chance to do any damage.Leave the plant outside for a few days to acclimate to its new container, provided there is no frost in the forecast.A lightly heated garage or hallway is a good option, as warm indoor air can cause the plant to dry out. .
Growing Rosemary in USA
Rosemary will grow from seeds but this is not recommended as the success rate is very low. .