How to Grow Lavender in Cold Climates

Lavender is a perennial herb favored by many gardeners, including those in cold climates. The key is to plant a suitable variety, site the shrub correctly and provide adequate air circulation to avoid disease issues like fungus.

Grow lavender plants from nursery starts or seed, and transplant when the soil has warmed in spring. This speeds up the establishment process by directing energy into the root zone.

Soil

Lavender plants are sun lovers and require a well-drained soil. They are prone to root rot in waterlogged soil, so the best option for them is a sandy loam or gravelly type of soil. The pH level of the soil should be slightly alkaline, between 6.5 and 8.0. Lavender plants are also tolerant of clay soil, provided it is not too wet and is amended with plenty of coarse-textured compost or builder’s sand at planting time to make sure it drains well. Lavender also grows well in raised beds and on slopes, which will help with drainage, as will a layer of light mulch, such as pine bark or pebbles.

If you are starting lavender from seed, it is best to grow it indoors in a container with sterile seed starting mix. Sow the seeds in early spring and keep the mix moist, but not wet, until the seedlings are ready to transplant. Lavender is easy to propagate by cutting the stems at their lowest node and removing 3-4 of the lower leaves. Dip the cut end of each stem in a solution of equal parts water and rooting hormone, and then set the cuttings in warm, but not hot, water. Keep the soil lightly moist and warm until they start to grow roots, then transplant them to your garden or containers.

To ensure that lavender plants get the proper amount of drainage, plant them in high mounds or on slopes, and work in plenty of coarse-textured compost or builder’s soil to “open up” the heavier clay types. The ideal soil is a dry, sandy loam, but any type of well-draining soil will do. Lavender also does well in pots, provided it is planted with a good drainage soil like clay or lava rock, and the pot is one size larger than the roots.

Water

Lavender is drought tolerant once established, but the plant needs to be tended to its watering schedule like any other garden plant. Generally, lavender plants should be watered when the soil is nearly dry. The frequency of this depends on the seasons, with summer calling for more frequent watering, and winter’s dormancy necessitating less. Other factors, such as soil type, also play a role. Sandy soil tends to dry out faster than gossip at a small-town coffee shop, and thus requires more frequent watering than loamy or clay soils.

Using a moisture meter or finger test is the best way to know whether or not lavender needs water. To test for dryness, dig your digit into the soil up to the second knuckle. If it feels dry and looks dull, that’s your cue to water. Depending on the weather, you might need to water more frequently if the sun is beating down on your lavender like a drum at a rock concert.

When the weather turns cooler and your lavender goes into dormancy, reduce the frequency of watering. However, be vigilant: lavender can easily rot in overly wet soil.

To ensure your lavender has the right amount of nutrients, fertilize the plant once a year in spring. Alternatively, you can use an organic or slow-release plant food to keep the lavender healthy and happy throughout the season. This will encourage abundant flowers and vigorous growth. To ensure the health of your lavender, you should also mulch around the plant to help regulate soil temperature and moisture levels.

Light

Lavender plants love sunlight. Too little of it, and you’ll get a stunted, sparse plant that produces few flowers. Ample sun, however, encourages vigorous growth, lush foliage and abundant blooms. Lavender thrives in sunny, well-draining soil that’s slightly alkaline with a pH between 6.5 and 7.5. The best soil for growing lavender is loose and sandy, but you can amend clay or loamy soil with organic matter or inert materials such as rice hulls to improve drainage. Avoid using chemical fertilizers, as they can promote excessive vegetative growth at the expense of flower production.

If you want to grow lavender from seed, sow seeds in a sterile seed starting mix and barely cover them. It may take up to a month for them to sprout, but warm temperatures and bright sunlight speed up the process. Lavender plants grow quickly and produce abundant flowers in summer, which you can cut to enjoy the fragrance or to use for cooking. The plants reach peak bloom during their third year.

In areas where the sun is intense, consider planting your lavender near trees or structures that cast afternoon shade. This helps protect the plants from wilting and sunburn while maximizing sunlight exposure during the shorter days of winter.

In general, it’s a good idea to prune lavender plants lightly in spring after the first flush of bloom, late summer after the second bloom flush and mid-to-late fall. This stimulates growth, keeps the plants tidy and healthy and promotes future blooming. Be sure to use sanitized pruning tools. You can also harvest faded blooms throughout the season to encourage additional flowering. If the plants are crowded, thin them by cutting back the old wood in the spring or fall.

Pruning

As lavender plants mature they can get very bushy. It is important to prune them regularly to encourage more blooms and prevent the plant from becoming floppy. In addition, yearly pruning can also help prevent lavenders from becoming overgrown and susceptible to diseases such as Septoria leaf spot and Phytophthora crown and root rots.

Pruning lavenders is a relatively easy process, especially for those who are familiar with cutting herbs such as thyme and sage. A pair of hand pruners or a set of hedge shears will be perfect for the job. Before you begin, remember to sanitize your tools with rubbing alcohol or disinfecting wipes so that you don’t introduce disease to the lavender plants.

When pruning, start at the top of the plant and remove any dry flowers that are still attached. Next, look for where the woody base of the plant meets new foliage growth and cut just above that point. Avoid cutting into bare, old woody growth as lavenders do not regenerate on bare woody stems.

Once you have trimmed back the old growth, look for new buds that are just beginning to form. Prune out any dead flower heads and their stems as well as any old, twiggy growth that hasn’t produced flowers for quite some time.

While some gardeners choose to prune their lavenders in the fall, this can actually be counterproductive. Lavenders that are pruned in the fall will tend to put out tender, new growth that can be killed by frost or weakened by snow. This can be especially problematic for lavender plants that are grown in containers and overwintered outdoors. It is better to wait until spring to prune the lavenders once they are in full bloom.

Harvesting

Lavender plants should be harvested after a large number of flowers have opened and are at their peak, typically in mid- to late summer. This allows the oil content to remain high. Harvesting too early can induce woody growth and reduce the essential oils in the buds.

When ready to harvest, simply snip off the flower heads from each stem. The flower heads can be used for dried bouquets, or a simpler option is to shake the whole lavender plant off the stems and store them in an airtight jar. The dried buds can also be used for making sachets to keep sheets, clothes and other linens smelling sweet and to repel moths.

Whether you are cutting the whole plant or just the flowers, make sure the weather is dry before harvesting. This minimizes the chances of fungi developing in the damp lavender, and it allows the buds to dry quickly.

In addition to regular harvesting, the plant should be pruned at least once per year. This promotes vigorous new growth and keeps the plant looking neat and tidy, which is particularly important if you plan to use your lavender for cutting. Pruning can be done in spring or fall, but not before flowering.

Lavender plants are heat and frost tolerant, and grow well in containers. However, they are slow-growing and need a lot of light to stay healthy and bloom regularly. The best time to plant them is in the spring, although they can also be planted in the fall if you allow enough time for them to establish before winter. Planting them in sandy, well-drained soil is ideal. Lavender plants can also be grown in poorer soil if given ample light, but they won’t thrive in shady locations and may not flower as readily.