When to Plant Fall Flower Bulbs: South Atlantic Coast
Region "D" — South Atlantic Coast
Optimum Planting Time:
October 15th - December 15th
USDA Hardiness Zones:
Yours is a moderate climate with hot moist summers and cool to cold moist winters. You will be able to grow an enormous number of spring-flowering bulbs successfully. However, due to your moist conditions, only specific bulb cultivars will perennialize well. Local experts and garden centers will have recommendations.
Plant bulbs in the fall, starting when nighttime temperatures stay between 40-50°F. But be sure to plant approximately six weeks before the ground freezes to allow sufficient time for rooting. Flower bulbs will root best in cool soil and once rooted undergo natural changes that keep them from freezing. Water your bulbs after planting to help them start the rooting process.
After planting, apply slow release "bulb food" fertilizer on the top of the ground to supply nutrients for the second year's bloom. (Fall bulbs are already fully charged with energy for peak flowering performance in their first spring bloom season.) Do not put the fertilizer in the hole with the bulb's tender roots.
Please note: Modern bone meal often draws rodents and dogs that dig up the bulbs looking for bones!
After the ground cools or freezes, cover your beds with a lightweight mulch (pine needles, buckwheat hulls, straw, or chopped up leaves) 2 — 4 inches thick to help keep down weeds and maintain a consistently cool soil temperature.
Special Note: Most spring-flowering bulbs need to remain relatively dry during their dormancy. Do not plant them where you have 'mindless summer irrigation' (a sprinkler system that comes on like clockwork, whether you need it or not). Planting in elevated beds (6"-12" above normal soil level) will help to alleviate this problem and aid in perennialization.
A Sampling of Flower Bulbs for Perennializing (Return for Several Years):