1/8"; needs darkness to germinate.
Recommended. Direct sow in early spring 3-4 weeks before last frost, or early autumn in zones 7-10.
PLACEMENT & CULTIVATION
Nothing could be finer than to have clouds of gem like petite flowers to set off larger-flowered spring and summer annuals. Larkspur 'Blue Cloud' is a great filler for bouquets too! Blooms all summer in moderate heat areas. A fall sowing can be made in zones 6-7, when they will germinate and establish before winter and most likely live over in all but the most severe winters.They can tolerate some heat and drought but perform best where summer nights cool down. Caution: all parts contain toxic alkaloids.
Water regularly, particularly during dry periods, but avoid saturated soils. Somewhat drought tolerant, but best flowering with regular water.
Slightly acidic to slightly alkaline; if soil is very acidic, add lime before planting.
Mix in 2-4" of compost prior to planting.
Diseases & Pests:
Susceptible to fungal problems in poorly drained locations, or where foliage stays wet. Space to allow for good air circulation and use organic fungicides or neem oil if needed.
When to Cut for Bouquets:
Harvest when about 1/2 of the florets are open.