Delphinium (_Larkspur_).--The gorgeous spikes of flowers produced by
these plants render them invaluable for the border. They like a deep
soil, highly enriched. The perennials may be divided at the root in
autumn, care being taken not to injure the young fleshy sprouts. The
annuals are readily raised from seed. The quickest way to grow the
perennial varieties from seed is to sow in a frame with a slight
bottom-heat, at any time from March to August; but sowings made in the
open from April to June will succeed. Keep the ground moist, and shade
from the sun till the plants are up, then transplant to nursery beds
for the summer, afterwards transferring them to their final quarters.
Flower in June and July. Height, 1-1/2 ft. to 6 ft.
Dentaria Digitata (_Toothwort_).--This tuberous hardy perennial grows
well in old leaf-mould, and is very suitable for the base portion of
rock-work, where it can obtain both shade from the midday sun and
moisture. It is readily increased by cutting the roots into pieces
about 1-1/2 in. long, and replanting them where they are intended to
bloom, putting 1 in. or so of sand round them. They flower in May.
Height, 1-1/2 ft.
Desfontania Spinosa.--A fine, evergreen wall shrub with holly-like
leaves, and long, pendulous scarlet and orange flowers in June. It
grows best in a compost of loam, peat, and sand, with a south or west
aspect. It is propagated by cuttings under glass. Height, 10 ft.
Desmodium Canadense.--This is a fine border hardy perennial, producing
long racemes of rosy-purple flowers in June or July. It prefers a soil
of sandy loam and peat, and may be increased by seed or by cuttings
planted in sand and subjected to heat. Height, 4 ft.
Desmodium Pendulaeflorum.--A hardy evergreen shrub, flowering in July.
It thrives in sandy loam and peat. Cuttings planted in sand with a
little bottom-heat and under glass will strike. Height, 6 ft.
Deutzia.--A beautiful conservatory shrub, bearing in spring a large
quantity of flowers resembling the snowdrop. A peaty soil suits it. It
is pretty hardy. Height, 3 ft.