Provence Blue has a mature size of 24 inches high and wide. Lavenders need excellent air circulation, so space Provence Blue plants 24 inches apart. This variety is hardy in U.S. Department of Agriculture Plant Hardiness Zones 5 through 9.
English lavenders are slow growers; expect 10- to 12-inch plants the second year after planting from seed, with the plant reaching full size in its third year.
Lavenders grow quickest in full sun and well-drained soil. Keep the soil pH neutral to slightly alkaline, 7.0 and above. Although drought tolerant once established, obtain the best growth with supplemental watering as long as soil drainage is excellent. Water once or twice a week after planting and when the plant begins sending up flower stalks.