How Big Does French Lavender Grow? A Complete Guide

French lavender (Lavandula dentata) is one of the most popular lavender varieties grown in home gardens. With its iconic purple blooms and serrated grey-green leaves, this hardy lavender variety adds beauty and fragrance to any landscape. But exactly how big does French lavender get? Read on to learn all about the mature size of this classic perennial.

Overview of French Lavender

French lavender is native to the Mediterranean region and is more tolerant of heat and humidity than other lavender varieties. It produces light purple flowers on long stems from late spring through fall. The foliage is finely serrated and emits a camphor-like fragrance when crushed.

While not as sweetly scented as English lavender, French lavender is less prone to common lavender diseases like root rot and mildew. Its loose, informal growth habit makes it excellent for informal hedges, borders, and mass plantings. Let’s take a closer look at how big this variety grows.

Mature Height of French Lavender

On average, French lavender reaches a mature height of 2 to 3 feet (60-90 cm) tall. However, some cultivars may grow slightly shorter or taller

• Dwarf French lavender cultivars like ‘Melissa Lilac’ and ‘Anouk’ grow 12 to 18 inches (30-45 cm) tall.

• Larger cultivars like ‘Folgate’ can reach up to 4 feet (120 cm) at maturity.

• Most standard French lavender plants will grow 2 to 3 feet (60-90 cm) tall at maturity in ideal conditions.

Soil fertility, sunlight exposure, and climate can also impact mature height Rich soils tend to produce more vigorous growth Meanwhile, plants grown in shade or extreme heat may stay more compact.

Mature Width of French Lavender

The width of French lavender at maturity largely depends on the cultivar as well:

• More compact varieties reach 1 to 2 feet (30-60 cm) wide.

• Larger cultivars can spread 3 to 4 feet (90-120 cm) across

• On average, mature French lavender plants grow 2 to 3 feet (60-90 cm) wide.

Proper spacing during planting helps restrict width. Allow at least 2 to 3 feet (60-90 cm) of space between plants to prevent overcrowding. Pruning and shearing established plants controls width by keeping growth compact.

Growth Rate

French lavender is relatively fast-growing, especially when grown in loose, sandy soils under full sun. Here’s what to expect:

• In warm climates, first-year plants may reach 18 inches (45 cm) tall and wide.

• Most plants take 2 to 3 years to fully fill out to their mature height and width.

• Once established, French lavender grows at a moderate rate of 6 to 12 inches (15-30 cm) per year.

Healthy plants can live 5 years or longer in ideal conditions. Staggering new plantings every 2 to 3 years ensures a continual supply of young, vigorous plants.

Height Factors

Several cultural and environmental factors can affect the eventual mature height of French lavender:

Soil conditions – Plants reach larger sizes in loose, sandy soils. Growth may be stunted in heavy clay or perpetually damp soils.

Sun exposure – At least 6 hours of direct sun per day is required for French lavender to reach its full size. Too much shade results in sparse, leggy growth.

Climate – Hot, dry climates tend to produce larger plants than cool coastal regions. Protect plants from harsh winter winds in cold climates.

Pruning and shearing – Regular pruning controls size by removing old wood and shaping plants. Avoid shearing too often as this can weaken plants over time.

Cultivar – Compact cultivars have an inherently smaller mature size than larger varieties. Select cultivars suited to available space.

Spacing – Allow enough room between plants to prevent overcrowding and competition for resources. This encourages plants to grow freely to their mature dimensions.

Width Factors

The eventual width of French lavender also depends on various growing conditions:

• Loose, fast-draining soil provides room for roots to spread out.

• Full sun exposure prevents lanky, spaced-out growth.

• Ample spacing prevents competition between plants.

• Routine pruning keeps growth compact and prevents bare lower stems.

• More compact cultivars have a naturally smaller mature width.

• Excess shade or fertilizer can cause plants to grow leggy as they reach for light and nutrients.

Size in Containers

French lavender adapts well to container growing. Limit pot size to restrict growth. A 12-14 inch (30-35 cm) diameter pot is sufficient for most plants. Select dwarf cultivars for smaller containers. Grow in a lightweight potting mix and allow pots to fully dry out between waterings. Move containers to a frost-free location in winter. Rejuvenate potted plants every 2 to 3 years by taking cuttings or replacing with fresh plants.

Tips for Managing Size

Here are some tips to control French lavender’s growth:

• Space plants 2 to 3 feet (60-90 cm) apart to prevent crowding.

• Prune annually after flowering to remove old wood and shape plants.

• Shear established hedges and borders lightly in midsummer to shape and compact growth. Avoid heavy shearing.

• Grow dwarf cultivars like ‘Anouk’ and ‘Melissa Lilac’ for smaller spaces.

• Use gravel mulch to keep soil dry and restrict vigorous growth.

• Reduce water and fertilizer to limit growth in rich soils.

Achieving the Best Size

With its airy purple blooms and refined foliage, French lavender adds beauty, fragrance, and texture to both formal and informal garden designs. Allow enough space for this versatile Lavandula variety to grow to its mature size for maximum impact. Annual pruning and proper care will keep plants looking their best year after year.