Van Bourgondien

Garden Guide Bulbs and Tubers

Varieties

Dahlia imperialism

(Tree Dahlia) Plant in a warm and sunny area in the garden. Plant tuber in welldrained soil, 6" deep and spaced 6-7 feet apart. Grows 20-29 feet tall, blooming in late August until frost. Hardy in zones 8-10; elsewhere dig and store in a frost-free area over the winter.

Dahlias

Dahlias can be started indoors in individual pots with damp peat moss and vermiculite. Care MUST be taken in transplanting them outdoors. Plant dahlias outdoors after all danger of frost has passed. Choose a sunny site with well-drained, sandy soil. Dig soil to a depth of 12". Amend soil with peat moss or compost. Replace about half the soil, then place tubers flat and cover with remaining soil. Space tubers 12-36" apart depending on variety. Water after planting and not again until shoots appear. Stake plants. As plants grow, increase watering. Fertilize sparingly. Pinch and disbud dahlias for later and larger flowers. Buds tend to grow in threes; two-sided ones should carefully be pinched to develop the central bloom. This is especially important with border or pot plant dahlias. If the plants are not pinched back, they will not retain their low, compact size. An exception to this would be the Dahlianovas, which do not require pinching. In areas with winter freeze, carefully dig the tubers in fall after the frost kills the foliage. Cut the stalk approximately 6" above the tuber. Allow tubers to dry thoroughly. Pack them carefully in dry sand, peat moss, or sawdust and store in a cool (40-45°) dry place. In the spring, separate tubers from stalk. Leave 1" of stalk attached to each tuber which must have an eye or bud to bloom. Height and bloom times listed abovd. Hardy in zones 8-10.

Dichelostemma

Plant corms in the fall 4–5" deep and 3" apart in well-drained soil in full sun. They require excellent drainage and dry conditions after blooms. In areas with wet summers, dig after foliage fades and replant in the fall. In colder regions, mulch after fall planting. May be planted in containers in the fall in a well- draining soil with 4-5 corms per 6" container. Store in a cold frame over winter. In late winter, bring containers indoors into a cool, sunny location and keep soil moist. Grows 12-35" tall and 18- 24" wide. Blooms June-July. Hardy in zones 5-7.

Dog Tooth Violet

See Erythronium

Dracunculus vulgaris

(Dragon Arum) Should be planted with the flat side of the bulb up, about 3" deep in rich, moist soil. They do excellent in the wild garden or by the waterside. They flourish in a sunny or a somewhat shady area. The bulbs should be planted 12-16" apart. Water after planting. In areas with severe frost, a winter cover is necessary, especially the first winter after planting. After flowering, it is best to top-dress the plant with top soil or other rich organic matter and cultivate into the ground around the plant. Blooms May-June. Hardy in zones 6-9.

Dragon Arum

See Dracunculus vulgaris

Drumstick Allium

See Allium

Dutch Iris

See Iris hollandica

Easter Lily

See Lilium

Egret Flower

See Habenaria radiata