and therefore to grow more rapidly. Of course, if still earlier results
are desired, the seed should be sown in the kitchen, hotbed, coldframe,
or in a greenhouse. In starting plants ahead of the season, be careful
not to use too deep boxes. The gardener's "flat" may be taken as a
suggestion. Three inches of earth is sufficient, and in some cases (as
when the plants are started late) half this depth is enough.
The difficulty with early sown seedlings is "drawing up," and weakness
from crowding and want of light. This is most liable to occur with
window-grown plants. Vigorous June-sown plants are better than such
weaklings. It must be remembered that very early bloom usually means the
shortening of the season at the other end; this may be remedied to some
extent by making sowings at different times.
The "hardy" annuals are such as develop readily without the aid of
artificial heat. They are commonly sown in May or earlier, directly in
the open ground where they are to grow. Florists often sow certain kinds
in the fall, and winter the young plants in coldframes. They may also be
wintered under a covering of leaves or evergreen boughs. Some of the
hardy annuals (as sweet pea) withstand considerable frost. The
"half-hardy" and "tender" annuals are alike in that they require more
warmth for their germination and growth. The tender kinds are very
quickly sensitive to frost. Both these, like the hardy kinds, may be
sown in the open ground, but not until the weather has become settled
and warm, which for the tender kinds will not commonly be before the
first of June; but the tender kinds, at least, are preferably started in
the house and transplanted to their outdoor beds. Of course, these terms
are wholly relative. What may be a tender annual in Massachusetts may be
a hardy annual or even a perennial in Louisiana.
These terms as ordinarily used in this country refer to the northern
states, or not farther south than middle Atlantic states.
Some familiar examples of hardy annuals are sweet alyssum, ageratum,
calendula, calliopsis, candytuft, Centaurea Cyanus, clarkia, larkspur,
gilia, California poppy, morning-glory, marigold, mignonette, nemophila,
pansy, phlox, pinks, poppies, portulaca, zinnia, sweet pea, scabiosa.
Examples of half-hardy annuals are: China aster, alonsoa, balsam,
petunia, ricinus, stocks, balloon-vine, martynia, salpiglossis,
thunbergia, nasturtium, verbena.
Examples of tender annuals: Amarantus, celosia or coxcomb, cosmos,
cotton, Lobelia Erinus, cobea, gourds, ice-plant, sensitive-plant,
solanums, torenia, and such things as dahlias, caladiums, and acalypha
used for bedding and subtropical effects.
Some annuals do not bear transplanting well; as poppies, bartonia,
Venus' looking-glass, the dwarf convolvulus, lupinus, and malope. It is
best, therefore, to sow them where they are to grow.
Some kinds (as poppies) do not bloom all summer, more especially not if
allowed to produce seed. Of such kinds a second or third sowing at
intervals will provide a succession. Preventing the formation of seeds
prolongs their life and flowering period.
A few of the annuals thrive in partial shade or where they receive
sunshine for half the day; but most of them prefer a sunny situation.