Excerpt
from The All-New Illustrated Guide to Gardening
by Trevor Cole and Fern Marshall Bradley
Annuals and Biennials
A garden can be quickly filled with
color by using annuals and
biennials. These plants flower longer than many others and are ideal
for filling gaps
in a border.
Almost any patch of soil can be transformed into a blaze of
color in a matter of weeks by planting nursery-grown annuals, or in two
or three months with the plants you grow from direct-sown seeds.
Annuals are plants that grow, flower, produce seeds, and die in one
growing season. The most popular kinds provide a longer-lasting display
than perennials or bulbs, and they are invaluable for starting a new
garden quickly. They can also be used to supply bright accents among
shrubs or perennials, under trees, and in containers. Many of these
plants provide excellent cut flowers as well.
Most annuals are inexpensive, easy to grow, and available in a broad
range of colors and heights.
Plants that are similar in their general effect are biennials. They are
started from seeds one year; they flower the next; and then they die.
In mild climates, however, some of the plants grown as annuals may
survive the winter (they actually are tender perennials), and some
biennials can be grown as annuals.
Annuals are classified in some books and catalogs, and on some seed
packets, according to the British system, which divides them into two
groups -- hardy and half-hardy. Hardy annuals, which tolerate cold
weather, can be sown earlier than halfhardy annuals. This terminology
often proves more confusing than helpful, however, because it does not
apply to all areas of North America. Therefore, it is not used in this
book.
The quickest and easiest way to enjoy flowers in the garden is to
purchase young annuals or biennials in plant form in spring (also in
autumn in the South) and set them directly in the garden. A wide choice
of plants is available, but seeds, especially those offered in
catalogs, provide an even greater diversity.
Seeds can be given an extra early start (especially in cold regions) by
sowing them in a protected and controlled environment. This is almost a
necessity for very fine seeds, such as those of the wax begonia; for
seeds that need high temperatures to germinate, such as those of the
impatiens; and for those plants that are slow to bloom from seeds, such
as the vinca, petunia, and ageratum. Seeds can be started indoors if
sufficient light and proper temperature are provided (see p. 193), or
outdoors if a cold frame or hotbed that protects them from the elements
can be located conveniently.
Seeds can also be sown directly outdoors where they are to flower. This
is a popular and practical method for plants that bloom quickly, as
well as for those that have large seeds (see p. 191).
Biennials, although fewer in number than the annuals or perennials,
have some of the showiest garden flowers. Particularly popular
are sweet William, Canterbury bell, foxglove, hollyhock, and
pansy. They are usually sown in the late spring or early summer
outdoors in a protected location.
When biennial seedlings are large enough to handle, they can be
transplanted in rows to grow until late summer. By then they should be
sturdy enough for transplantation to permanent positions or to spend
the winter in a cold frame.
Many annuals and biennials have been garden favorites for centuries. A
worthwhile advance in recent years has been the development of the F1,
first generation, and the F2,
second generation, hybrids (the F stands for filial). They are the
result of selecting and inbreeding different parent lines of the same
plant to get the most desirable characteristics and then
cross-pollinating the plants to combine the best characteristics of
each.
Several generations of this kind of breeding are required to produce
plants of the desired quality. Some home gardeners may be deterred by
the relatively high price of the seeds, especially since seeds saved
from such hybrid plants will not produce plants of equal vigor or
identical color the next year.
But the first generation of flowers grown from F1
hybrid seeds will demonstrate such superiority to the less expensive
types that they are well worth the added cost. These hybrids offer
clearer colors, more vigor, larger size, greater weather and disease
resistance, and better, more uniform growth habits than their forebears.
F2 hybrids are the results of the
hybridizers' attempts to improve the quality without the high cost of
the F1 method. This is achieved by
selffertilizing the F1's. In some cases
it has worked. Generally, the F2 hybrids
are an improvement on standard seeds, though not so spectacular as the F1's.
Most seed catalogs do not mention the designations, but the difference
in the price is usually an indication that the most expensive seeds are
F1 hybrids or a new variety.
Selecting varieties from a catalog or seed rack can be confusing. In an
attempt to simplify the choice, All-America Selections, founded in
1932, began growing new varieties submitted by hybridizers in official
test gardens throughout the continent. Those awarded the highest number
of points are designated as the All-America Selections, and every seed
packet of those varieties is so labeled. The buyer can be assured that
these varieties have proven to be superior to other plants under varied
climatic and soil conditions.
Among most recent All-Americas are petunia 'Opera Supreme Pink Morn', a
ground cover that flowers profusely; celosia 'Fresh Look Gold',
free-branching and weather-tolerant; dianthus 'Supra Purple',
long-flowering and heat-tolerant; cleome 'Sparkler Blush', with pink
flowers that turn white with age; gaillardia 'Arizona Sun', with dark
red flowers with petals tipped in yellow on a spreading plant; and
zinnia 'Magellan Coral', with fully double flowers on a 12-inch plant.
Other All- Americas are indicated by an asterisk on the chart beginning
on page 197.
The above is an excerpt from the book The All-New Illustrated Guide to Gardening: Planning - Selection - Propagation - Organic Solutions by Edited by Fern Marshall Bradley and Trevor Cole. The above excerpt is a digitally scanned reproduction of text from print. Although this excerpt has been proofread, occasional errors may appear due to the scanning process. Please refer to the finished book for accuracy.
Copyright © 2009 Fern Marshall Bradley and Trevor Cole, editors of The All-New Illustrated Guide to Gardening: Planning - Selection - Propagation - Organic Solutions