Biennials.--These plants take two years to flower, and then they die
away altogether. The seed of the hardy varieties is sown thinly in
the open border any time between April and June, and the plants
transferred in the autumn to the place where they are intended to
bloom. Seed is also sown in August and September for flowering the
following year. The half-hardy kinds may be sown in May or June. These
require protection during winter, such as is afforded by a cold pit,
frame, or greenhouse, or the covering of a mat or litter.
Bignonia _(Trumpet Flower_).--This is admirably suitable for a south
wall, but it requires plenty of room. It is propagated by cuttings
placed in sand, or by cuttings of the root. These should be planted
out in the spring, or autumn will do if they are covered with a
hand-glass.