French lavender is famous for its iconic purple blooms and its ruffled, serrated leaves. Though this common name is sometimes also used for another species of lavender—Lavandula stoechas—the name is not commonly used in the U.S. for Lavandula dentata, the species described in this growing guide.
Although it is adorned with its famous purple blooms, French lavender is not as fragrant as English lavender (Lavandula angustifolia). In warm, frost-free climates, French lavender blooms year-round. In areas that receive frost, French lavender blooms from spring to fall. Though beautiful, French lavender is not often used for culinary purposes because of its poor flavor. What it lacks in taste it makes up for with its uniquely serrated, ruffled appearance.
|Botanical Name||Lavandula dentata|
|Common Name||French lavender, fringed lavender|
|Mature Size||23-36 inches tall, 23-27 inches wide|
|Soil Type||Sandy, Well-drained|
|Soil pH||Neutral, Alkaline|
|Bloom Time||Spring, Summer, Fall, Winter|
|Hardiness Zones||8-11, USDA|
|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 condition is the most important requirement to grow 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 insects, 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 itself before the heat of summer. French lavender can 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 might 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; it does not grow well in nutrient-rich, fertile soils. Gravel mulch is a great option for topping the soil around French lavender. The gravel helps drain away excess water and moisture. Heavy or clay soils should be amended with small-sized bark mulch, pea gravel, or sand to improve drainage.
French lavender is extremely drought-tolerant and prefers to grow in dry conditions. Because of this, you will most likely not need to water French lavender unless in cases of extreme heat and drought. New plants appreciate more water when first planted, but they do not require consistent water after becoming established. Watering every few weeks will be fine until blooms appear. After that, switch to weekly or twice weekly watering until you harvest the blooms.
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. French lavender thrives with very few nutrients, while too many nutrients can harm this plant, often causing leggy, yellowed foliage and few flowers.
In regions with mild winters, prune French lavender in the fall. In 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 and well-defined shape. Using sharp snips, round out the plant to the desired shape. Be sure to avoid any old, woody growth, and only prune the young, soft growth. Old, woody growth will not grow new shoots.
Propagating French Lavender
French lavender is easily propagated from cuttings:
- 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 stem cutting.
- Gently press the cut end into a pot filled with well-draining potting soil or horticultural vermiculite, covering the stem up to the point just below where the leaves begin. There is no need to use a rooting hormone.
- Keep the soil moist until the plant is established and has developed a root system.
- Alternatively, you can place your cuttings in a glass of water until roots develop. Be sure the water does not touch the leaves. When roots develop, place the cutting into a pot filled with well-draining potting soil.
How to Grow French Lavender From Seed
Growing French lavender from seed requires patience and specific conditions. Seeds germinate best when collected and started in the fall.
- Fill small pots with potting soil, sprinkle a few seeds on top, and then lightly cover the seeds with soil.
- Overwinter the pots in a cool place such as in a cool greenhouse. Alternatively, you can start the seeds indoors by placing the pots in a refrigerator for a few weeks. Germination should occur in about one month.
- Keep the soil lightly moist, but do not cover the seeds with plastic because doing so retains too much moisture.
- If pots are in the refrigerator, remove them and allow them to come to room temperature. If there is a low germination rate, return the trays to the refrigerator for another two weeks and repeat the process.
- When seedlings are large 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 when grown in pots. Pot-grown plants are necessary in cold winter areas because you can move the pots indoors to protect the plants. Terracotta pots are perfect for growing lavender because the porous material wicks away moisture 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 about 12 inches in diameter. Because potted plants do not have access to nutrient deposits in the ground, potted lavender might need to be fertilized with a light fertilizer during the growing season. If you choose to do so, add sparingly.
To overwinter potted plants in areas that are too cold for French 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.
Zimmermann, Karen. “Pruning Lavender.” Oregonstate.edu. N.p., 3 July 2019. Web