Dragon’s Head.—­See “Dracocephalum.”

Dryas Octopetala (Mountain Avens).—­A prostrate, creeping perennial which bears white Anemone-like flowers from July to September.  It thrives in peat, and is increased by seeds, cuttings, or division.  Not being quite hardy, protection should be afforded during winter.  Height, 6 in.

Dutchman’s Pipe—­See “Aristolochia.”

E

Earwigs, to Trap.—­An inverted flower-pot, containing a little dry moss or hay, placed on a stick, forms a good trap for these pests.  They will also congregate in any hollow stems of plants that may be laid about.  They may be destroyed by shaking them into boiling water.

Eccremocarpus (Calampelis).—­These climbing half-hardy perennials will grow in any garden soil, a light, loamy one being preferable.  Sow the seed in autumn on a slight hotbed, pot off, and winter in a greenhouse.  The plants will be ready to turn out on a warm south wall in April or May.  Cut them down in the autumn, and cover the roots with dry leaves:  they will shoot up again in the spring.  The foliage is dark and Clematis-like; the flowers are borne in clusters, are tube-shaped, and bright orange-scarlet in colour.  They are increased by cuttings.

Echeveria.—­Choice greenhouse evergreen shrubs.  They grow best in a sandy loam, with a little peat, mixed with pulverised brick rubbish.  Water must be given cautiously.  Young plants may be taken off the parent in October and pressed firmly, but without bruising them, in light, rich soil.  Cuttings should be left for a few days to dry before planting.  They flower in autumn.  In winter keep them in a cold frame, and as dry as possible.  Height, 1 ft. to 2 ft.

Echinacea Purpurea (Purple Cone Flower).—­A stately hardy perennial, very pretty when in flower, but hardly suitable for cutting purposes.  It likes a rich, light, loam soil and plenty of sunshine.  The roots may be divided in spring, after growth has fairly started.  It blooms during September and October.  Height, 2-1/2 ft.

Echinops (Globe Thistle).—­Coarse perennial plants, of stiff growth.  Any soil suits them, and they may be increased by dividing the roots.  They bloom in July.  Height, 4 ft.

Echium Creticum.—­A scarlet-flowering hardy annual which should be grown wherever bees are kept.  Sow in spring in any garden soil.  Height, 1-1/2 ft.

Edelweiss.—­See “Gnaphalium.”

Edraianthus Dalmaticus.—­A charming little herbaceous perennial which proves quite hardy in our climate, and well deserves a place in the rockery.  Plant in deep, rich loam, and cover the surface of the crown with 1/2 in. of coarse sand.  It may be propagated from off-sets, taken with as much root as possible as soon as flowering ceases.  Winter the young plants in a cold frame, and do not give them too much water, or they will rot.  They will bloom in July and August.  Height, 4 in.