Lavandula multifida, or Fernleaf Lavender or French Lace, is a highly aromatic, fast-growing, everblooming plant. It grows to about 4 inches tall on straight stems with fern-like gray-green leaves. Native to the warm climates of the northwestern Mediterranean and the Canary Islands, it resembles a perennial. It is technically a sub-shrub because it develops woody stems in winter hardy conditions. The plant produces blue-violet flowers that bloom in dense, showy terminal spikes (up to 2 ½ inches long) on stems that rise above the foliage to 6 to 18 inches.
In warm winter locations, the flowers bloom throughout the year, especially in summer when the plants are grown annually. Unprotected plants will not survive winter if temperatures drop below 20°F. Growing this lavender in sheltered locations with good winter mulch in Zone 8 is best. Full sun and well-drained soils are essential. Excellent, moist conditions can lead to root and stem rot, so soil drainage is necessary in winter. Remove faded flowers to promote continued blooming and maintain the plant's appearance. Pruning should be done in spring after new leaves appear.
This species of lavender differs from most others by having a much better tolerance for summer heat and humidity.