Light
Lavender plants grown in full sunlight is the best way to guarantee a lot of buds and big, full bushes.
Soil
Lean soil (soil without a lot of organic matter mixed in) will encourage a higher concentration of oils (and good smells), so go easy on the organic matter and fertilizer. Lavender plants prefer well-drained soil that is on the drier side, so if you’re using a traditional potting mix, be sure to add in some sand for drainage. An alkaline or especially chalky soil will enhance your lavender’s fragrance, while any pH below about 6.5 will likely cause lavender plants to be very short-lived.
Water
Lavender is a resilient plant that is extremely drought-tolerant once established. When first starting your lavender plants, keep them regularly watered during their first growing season. After that, they can handle extended periods of drought—in fact, too much water can lead to fungal disease and root rot.
Temperature and Humidity
Lavender can withstand a range of temperatures, and it’s usually dampness more than the cold that’s responsible for killing lavender plants. Dampness can come in the form of wet roots during the winter months or high humidity in the summer. If humidity is a problem, make sure you have plenty of space between your plants for airflow, and always plant your bushes in a sunny location. Protect lavender plants from harsh winter winds by planting them next to a stone or brick wall to provide additional heat and protection. If you live in an area where the ground routinely freezes and thaws throughout the winter, your lavender plants will benefit from a layer of mulch applied after the ground initially freezes to protect the roots.
Fertilizer
It’s a good idea to add a handful of compost into the hole when you are first starting lavender plants. Beyond that, feeding is not needed with these plants and can detract from the overall potency of your lavender.
Types of Lavender
There are many varieties of lavender, each boasting benefits and perks. Some of the most popular include:
English Lavender (Lavandula angustifolia): A varietal that’s available in several cultivars, including: ‘Munstead,’ an old-fashioned standard with blue-purple flowers; ‘Hidcote,’ a version favored for its dark purple flowers; ‘Jean Davis,’ a unique blend that produces pale pink flower spikes. Lavandin (Lavandula x intermedia): A varietal with several cultivars including: ‘Provence,’ which is particularly popular for drying; ‘Grosso,’ a highly disease-resistant and fragrant standard. Fringed lavender(Lavandula dentata): A bushy, spreading shrub varietal that produces dense purple-blue flower spikes that are only mildly fragrant. French lavender(Lavandula stoechas) : A beautiful Mediterranean varietal that is compact and bushy with fragrant, dark purple flowers.
Pruning
Although lavender plants get regularly pruned simply by harvesting the flowers, a bit of spring pruning is recommended to keep your plant well-shaped and to encourage new growth. Taller lavender varieties can be cut back by approximately one-third of their height, while lower-growing varieties can either be pruned back by a couple of inches or cut down to new growth. If you live in an area where lavender suffers winter die-back, don’t prune your plants until you see new green growth at the base of the plant. If you disturb the plants too soon in the season, they’re unlikely to develop new growth.
Harvesting Lavender
A major reason lavender is so prized is that its flowers keep their fragrance once dried. For best drying results, harvest the flowers as the buds first begin to open. Hang them in small bunches upside-down in a warm spot with good air circulation until dried. Besides being beautiful and aromatic, lavender flowers are also edible. They can be used raw in salads, added to soups and stews, used as a seasoning, baked into cookies, and brewed into tea. Use sparingly; a little lavender flavor goes a long way.
Propagating Lavender
Lavender plants are best propagated by either softwood cuttings (the soft, flexible tips of shoots) or hardwood cuttings (segments of shoots with woody stems). Softwood cuttings are available in the spring; hardwood cuttings are available in the fall. Both processes can be done relatively the same—here’s how:
Potting and Repotting Lavender
Where outdoor planting is not practical, growing lavender in a ceramic, clay, or terra-cotta pot and moving it around to follow the sun or even bringing it indoors for the winter, will be most efficient. Lavender prefers to grow in a tight space. A pot that can accommodate the root ball with a couple of inches to spare is a good choice; a pot that is too large will encourage excessive dampness. Ensure that your container has plenty of holes at its base for drainage—root rot is one of the few problems experienced by lavender plants. Additionally, you can plant lavender in a clay or terracotta pot to help wick moisture away from the soil and keep it from getting too wet. Use a loose, soilless mix for planting, and remember that container-grown lavender will require more water than garden-grown plants. A good rule of thumb is to water when the soil (not the plant) appears dry, watering at the base of the plant to limit dampness on the foliage.
Common Pests & Plant Diseases
Lavender plants are not afflicted by many diseases. They may develop phytophthora, which is a soil-borne fungal disease that causes root and stem rot. Lavender can also succumb to septoria leaf spot, which is caused by a fungus and is also commonly found on tomato plants. However, many common pests are attracted to lavender, including whiteflies, spider mites, leafhoppers, and spittlebugs (which do little damage). Water spray, insecticidal soaps, and neem oil can be helpful to eliminate pests. The four-lined plant bug (FLPB) is another pest that can be found sucking on lavender plant leaves and can be controlled by pesticides.
How to Get Lavender to Bloom
When you’re growing a plant as prized for its blooms as lavender, try to do all you can to get it to flower profusely. If you’re having a difficult time getting your lavender plants to bloom, there are a few issues that could be to blame. Soil that is too fertile can result in fewer blooms. Highly fertile soil promotes a lot of green growth at the expense of bud production. You can either relocate your plants or amend the soil with sand or gravel to aerate it and make it less nutrient-dense. You should also make sure that your lavender plants are getting at least six to eight hours of sunlight daily, which will result in the most productive blooming. If your plant isn’t getting that much light in its current location, you can cut back nearby foliage that may be overshadowing it, or replant your lavender in containers so you can move them around and “chase” the light. Lastly, pruning your plant each spring—even if the size is suitable for your space—can result in more frequent (and fuller) blooming. The reason: Lavender sets buds on new growth, so stimulating that process is a helpful signal to the plant that it should get growing.
Common Problems With Lavender
Lavender plants are fairly trouble-free, but problems can occur. Here are common issues you may encounter when growing lavender indoors or outdoors.
Leaves Turning Yellow
Leaves turn yellow if the soil is too wet. If the lower leaves are yellow, that definitely means you are overwatering the plant. Many lavender plants will perish if their soil gets too wet over the winter months.
Plant Smells Bad
You have probably overwatered your lavender plant. The plant may have root rot. If you have a potted lavender plant that you think has root rot, prune the dead or affected roots with a sharp and sterilized cutting tool and repot the plant to see if it’s salvageable.
Drooping Leaves
You have probably underwatered your lavender plant. In addition, the soil will feel parched.
Soil Is Always Wet
You have overwatered your lavender plant. See if you can remove any root rot and replant the lavender in new soil.
