French lavender is famous for its iconic purple blooms and its ruffled, toothed leaves. Though this common name is sometimes also used for another species of lavender—Lavandula stoechas—it is not commonly used in the U.S for Lavandula dentata, the species under consideration in this growing guide.
Although it is adorned with its famous purple blooms, French lavender is not as fragrant as English varieties of lavender. In areas without cold frosts, this variety of lavender blooms year-round. In areas with frost, it blooms from spring to fall. Though beautiful, French lavender is not often used for culinary purposes because of poor taste. What it lacks in taste, it makes up for with its uniquely toothed, ruffled appearance.
|Botanical Name||Lavandula dentata|
|Common Name||French lavender|
|Mature Size||12-36 in. tall, 48-60 in. wide|
|Soil Type||Sandy, Well-drained|
|Soil pH||Neutral, Alkaline|
|Bloom Time||Spring, Summer, Fall, Winter|
|Hardiness Zones||8-11, USA|
|Native Area||Europe, Mediterranean|
French Lavender Care
French lavender is very easy to care for and actually thrives with neglect. It needs sunny, hot, dry conditions to flourish. Soil conditions are the most important aspect of growing French lavender. It needs fast-draining, nutrient-poor, alkaline soil. Occasional pruning will help keep this lavender clean and blooming. Deadhead spent flowers to encourage more flowering.
This plant is not often bothered by pests or diseases. Lavender is actually a natural repellent for bugs, such as aphids. The only disease to watch out for is rot, which is caused by too much water. Plant French lavender in the spring to allow time for it to establish before the heat of summer. Alternatively, French lavender can also be planted in the fall in areas without harsh winter temperatures.
French lavender needs a lot of sunshine to thrive, so be sure to plant it in a very sunny location. While other plants may droop or wilt with intense direct sunlight, you should choose the sunniest, hottest place in your garden for French lavender.
Dry, well-draining, alkaline soil is important for the health of French lavender. This plant prefers poor soil conditions, as nutrient-rich soils can damage the plant. Gravel mulch is a great option for topping the soil around French lavender. This will help excess water and moisture drain away. Heavy or clay soils should be amended with small-sized bark mulch to improve drainage.
French lavender is extremely drought-tolerant and prefers to stay more dry than moist. Because of this, you will most likely not need to water this lavender variety unless there is extreme heat and drought. New plants appreciate more water when first planted, but they do not require consistent water after this. Watering every few weeks will be fine until blooms appear, when you should switch to weekly or twice weekly watering until harvest.
Temperature and Humidity
French lavender cannot handle frost, snow, or freezing temperatures. High humidity is another enemy to the French lavender plant. These plants like dry, warm areas. Think of the sunny, hot climates of the Mediterranean where this plant is native and try to mimic these conditions.
Because French lavender thrives in fast-draining, poor soil, there is no need to fertilize these plants. French lavender thrives with little nutrients, while too many nutrients can harm this plant, causing leggy, yellowed foliage and few flowers.
In regions with mild winters, pruning can be done in the fall. For other regions, prune at the end of winter into early spring, after the last frost has passed. Pruning lavender will help the plant maintain a pleasing shape. Using sharp snips, round the plant to the desired shape. Be sure to avoid any old, woody growth, only pruning the young, soft growth. Old, woody growth will not grow new shoots.
Propagating French Lavender
French lavender is easily propagated from cuttings. Here’s how to do it:
- Wait until new growth appears in the spring. It is best to take cuttings right after the plant has bloomed.
- Using clean snips, cut a stem where the new growth meets the old growth.
- If there happen to be any flowers, trim them off. Then remove all the leaves on the lower half of the cutting.
- Gently poke the stripped end into well-draining dirt, covering the stem just below where the leaves start. Keep the soil moist until the plant is established.
- Alternatively, you can place your cuttings in a glass of water until roots appear. Then plant these in the soil. Just be sure the water does not touch the leaves.
How to Grow French Lavender From Seed
Growing French lavender from seed requires patience and specific conditions. Here is how to do it:
- Seeds germinate the best when collected and started in the fall.
- Lightly cover the seeds and allow them to overwinter in a cool place, such as in a cool greenhouse. Alternatively, you can start them indoors by placing them in the refrigerator for a few weeks.
- Keep the soil lightly moist, but avoid covering the seeds with plastic as this will retain too much moisture.
- Remove the pots from the refrigerator and allow them to come to room temperature. Germination should happen in about 1 month. If there is a low germination rate, return the trays to the refrigerator for another 2 weeks, and repeat the process.
- When seedlings are big enough to handle, transfer them to their own pots or plant in the garden in the spring.
Potting and Repotting French Lavender
French lavender does very well in pots. This is especially useful for areas where the temperatures are too cold in the winter, as the pot can be taken indoors. Terracotta pots are perfect for lavender, since the porous material provides for better drainage and keeps the soil on the drier side.
French lavender will need to be repotted yearly to accommodate new growth. It will top out with a pot size around 12 inches wide. Because potted plants do not have access to nutrient deposits in the ground, potted lavender may need to be fertilized with a light fertilizer during the growing season. If you choose to do this, add sparingly.
To overwinter potted plants in areas that are too cold for lavender, bring the pot indoors before the first frost. Keep the pot in a cool area with bright light. Water sparingly throughout the winter, only providing enough water to keep the plant alive. For plants kept outdoors in areas with mild winters, no watering is required. Simply prune before winter, if you wish, and clear away any dead, organic material that will hold moisture.