Pelargonium.--The shrubby kinds will grow well in any rich soil; loam
and decayed leaves form a good compost for them. They require good
drainage and plenty of air and light while in a vigorous state.
Cuttings root readily in either soil or sand, especially if placed
under glass. Most of the hard-wooded varieties are more easily
increased by cuttings from the roots. The tuberous-rooted ones should
be kept quite dry while dormant, and may be increased by small
off-sets from the roots.
Pentstemon.--This charming hardy perennial is deserving of a place in
every garden. It may be grown in any good soil, but a mixture of loam
and peat is most suitable. The seed may be sown in April, and the
plants transferred when strong enough to their flowering quarters; or
it may be sown in a sheltered position during August or September to
stand the winter. It may also be increased by dividing the roots in
spring, as soon as growth begins. Cuttings of the young side-shoots
about 6 in. long may be taken at any period--the middle of September
is a good time; these should be placed under a hand-glass in sandy
loam and leaf-mould. These cuttings will flower the first year. It
blooms from May to October. Height, 2 ft.
Peppermint.--This may be grown on any damp or marshy soil, and
increased by dividing the roots.
Perennials.--These are plants that die down during the winter, but
spring up and produce new stems annually. Some, as for instance
Antirrhinums and Pansies, flower the first season, but usually they do
not bloom till the second season. Many of the species improve by age,
forming large clumps or bushes. The stock is increased by division
of the roots, which, if judiciously done, improves the plant. Like
annuals, they are divided into classes of Hardy, Half-hardy, and
Tender plants.
Hardy perennials do not require artificial heat to germinate the
seeds, or at any period of their growth, but are the most easily
cultivated of all plants. Seed may be sown from March to midsummer,
transplanting in the autumn to their flowering quarters; or it may
be sown in August and September in a sheltered position to stand the
winter.
Half-hardy plants require artificial heat to germinate their seed, and
must be gradually introduced into the open. They may be sown during
March and April in frames or a greenhouse, when many will bloom the
first season. If sown between May and the end of August they will
flower the following spring and summer. They require protection during
winter, such as is afforded by a cold pit, frame, or greenhouse, or
the covering of a mat or litter. Tender perennials may be sown as
directed above, but the plants should be kept constantly under glass.
Some perennials, such as Pinks, Carnations, Saxifrages, etc., do
not die down, but retain their leaves. These are called evergreen
perennials.