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Peas are an annual plant.

Of one season's duration from seed to maturity and death.

Standard Cyclopedia of Horticulture

Annuals. What are known to gardeners as "annuals" are plants that bloom in the open the same year the seeds are sown and that do not live over winter.

These plants are not necessarily true annuals; for annuals in the botanical sense are plants that normally complete their entire life- cycle within one vegetation-year. Perennial plants that bloom freely from seed the first year and do not usefully survive till another year may be classed as annuals by the gardener and treated as such: these are properly plur-annuals, a group standing midway between annuals and perennials. The garden Nicotiana affinis (properly N. alata) and pinks and snapdragons are such. It may be said that plur-annuals are plants of somewhat indefinite duration that are terminated by cold weather rather than by their normal maturity within the season. Many real perennials, as castor bean, are treated as annuals in northern gardens.

Some of the biennial plants—those that normally bloom and perish in the second year—may flower the first year if the seeds are sown early and the plants are hurried along. Of these, Canterbury bell, ipomopsis and some of the oenotheras arc examples. See Biennials.

The annuals of gardens are grown directly from seeds, in usual practice. Some plants are reared annually from bulbs or tubers, as crocus, lilies, potato: these are really perennials that die each year to the ground and do not perish root and branch. To these plants the name pseud-annuals (i.e., false annuals) has been given.

Among the true annuals there are many grades. Some of them are winter annuals, growing in the cool part of the year and carrying over winter under the snow, as the common creeping chickweed and other crucifers. In the arid regions of the West, many annual plants spring into growth with the rains and thrive in the cool months. Many of the annuals are summer annuals and others are autumn annuals: these two classes are practically the only ones that are cultivated in the open for ornament.

Among the annuals are found some of the most showy garden flowers. As a rule, they are easily grown, producing quick results and affording a great variety of colors, forms and foliage. Some of the annuals last only a few weeks in bloom, others continue throughout the summer. There are trailers and climbers, dwarfs and tall growers. By a judicious selection and arrangement of kinds, the handsomest effect may be produced. Many of the showy kinds are adapted to mass effects, while the dwarf-growing sorts make good flowering edgings for beds or walks. With the latter, handsome ribbon-beds are possible, but this requires care in the selection of kinds, and as the use of the trimming shears is almost precluded, it is best to limit oneself to simple designs. Annuals are well suited to the covering of bare spots of ground in the border. Like other flowers, they display best when seen against a background of foliage. The tall and leafy kinds make excellent covers for unsightly objects. For climbing and twining kinds, see Vines. See, also, Everlastings and Grasses. Classification as to hardiness.

It is customary to divide annuals into three classes: (1) Hardy annuals are those that are sown directly in the open ground where they are to grow. They are vitally strong, developing without artificial heat, and may be sown from February to May, according to the season and latitude. Some of them, as sweet peas, may be sown even in the fall. For this class, a well-prepared border on the south side of a fence or wall, or other sheltered place, is usually preferred for early sowings. From here the seedlings are transplanted later where they are to grow. Some sorts, however, do not bear transplanting well, consequently must be sown in the places they are to occupy. Among such are poppies, eschscholtzia, bartonia, Venus' looking-glass, lupine, malope, and the dwarf convolvulus. (2) Half-hardy annuals are usually sown in February or March in the window or a warm frame. The season is usually not long enough to enable them to reach full development in the open. In the early stages of growth they need protection and warmth. Such kinds are sometimes sown in the fall and wintered over in a coldframe. When once established, they are hardy with slight protection. Some of the kinds are grown 'to their greatest perfection only in this way. (3) Tender annuals require still more warmth, and are started from January to May in the greenhouse or other suitable place. They commonly need a temperature of 60° to 70°. The danger with early-grown seedlings, especially those started in the window, is over-crowding and want of light. As soon as crowding begins, the plants should be thinned out or transplanted to other trays, or into pots, and reset from time to time, as they need; frequent transplanting is usually an advantage. The last transplanting is preferably into small pots, as then the seedlings may be readily set in the open ground at the proper time, with little or no check.


The greater number of common annuals will bloom freely if the seeds are sown in the open ground when the weather becomes thoroughly settled. But there are some kinds, as the late cosmos and moonflowers, for which the northern season is commonly too short to give good bloom unless they are started very early indoors.

In the case of others than the continuous bloomers, a succession of sowings or plantings is desirable to provide for a continuous display; then as a kind begins to fail, its place may be filled with young plants of the same or other species. The usual method of securing succession is to sow the seeds in flats, or beds, and transplant the seedlings first to pots. The potted plants may be set out at any time, with but little check to growth.

When flowers of any annual are wanted extra early, the seeds should be started indoors. It is not necessary to have a greenhouse for this purpose, although best results are to be expected with such a building. The seed may be sown in boxes, and these boxes then placed in a sheltered position on the warm side of a building. At night they may be covered with boards or matting. In very cold "spells" the boxes should be brought inside. In this simple way seeds may often be started one to three weeks ahead of the time when they can be sown in the open garden. Moreover, the plants are likely to receive better care in these boxes, 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.

One trouble with early sown seedlings is "drawing up," and weakness from crowding and want of light. This is most likely to occur with window-grown plants. Vigorous June-sown plants are better than such weaklings. It must be remembered, however, 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.

Only the best seeds should be purchased, and it is usually best to get the colors in separate packets. In the open ground, seeds may be covered to a depth of four or five times their own thickness, but when sown indoors in trays or pots, the rule is to cover them to about their own thickness. After covering, the soil should be pressed firmly over the seed with aboard or hoe. or the feet. In soils that are inclined to bake, a sprinkling of sand or fine litter over the surface after sowing will remedy this evil. Evergreen boughs placed over the beds until the seedlings have appeared will afford useful shelter from beating rains. It is desirable to sow the seeds thickly. For the reception of seeds, the surface should be mellow and smooth. The seeds are sown in drills or concentric circles, according to the method of planting decided upon. Taller- growing kinds are sown toward the center or back of the bed. When up, the plants may be thinned to their proper distances. Particular care should be given to this matter, and to keeping down weeds, or the plants may become weak, spindling and valueless. Much trouble will be avoided if each seed-row is plainly labeled or marked so that the young plants may be distinguished from the weeds, with which they must often compete.

Soil and places.

Most annuals thrive best in an open, sunny situation, but pansies, forget-me-nots, and some others, thrive where they get the full sunshine for only half the day. Some of the kinds are at their best in full sunlight, as portulaca, sunflower, and zinnia. In all cases the best results are secured only when the soil is well enriched and thoroughly prepared previous to sowing or planting; and it is far better to make this preparation a fortnight or more in advance. A considerable proportion of humus in the soil is desirable, rendering it less subject to baking and drying out. Cow-manure, stable-manure or leaf-mold, worked in liberally, will supply this. Beds should be spaded thoroughly and at least a foot deep. If the surface is then again worked over to half this depth, better results will be obtainable. The soil should not be disturbed, however, unless it pulverizes readily.

When the flowers are to be grown about the edges of the lawn, make sure that the grass roots do not run underneath them and rob them of food and moisture. It is well to run a sharp spade deep into the ground about the edges of the bed every two or three weeks for the purpose of cutting off any grass root that may have run into the bed. If beds are made in the turf, see that they are 3 feet or more wide, so that the grass roots will not undermine them. Against the shrub borders, this precaution may not be necessary: it is desirable that the flowers fill all the space between the overhanging branches and the sod.

The plants should not be allowed -to bear seed, else they will be exhausted and the season of bloom will be short. Sweet peas, for example, soon spend themselves and dry up if the pods are allowed to ripen. The frequent cutting of blooms prolongs the season.

The kinds.

Most of the staple or general-purpose types of annuals in the North are the following: petunias, phloxes, pinks or dianthuses, larkspurs or delphiniums, calliopsis or coreopsis, pot marigolds or calendulas, bachelor's buttons or Centaurea Cyanus, clarkias, zinnias, marigolds or tagetes, collinsias, gibas, California poppies or eschscholtzias, verbenas, poppies, China asters, sweet peas, nemophilas, portulacas, silènes, candytufts or iberis, alyssum, stocks or matthiolas, morning-glories, nasturtiums or tropaeolums, wallflowers, gaillardias, snapdragons, coxcombs, lobelias, four-o clocks, amaranths, balsams, sweet sultans, salpiglossis, scabiosas, nicotianas, and pansies. Other species are mostly of special or particular use, not general-use types. In the South, and occasionally at the North, some of the annuals come up voluntarily year after year from self sown seeds, e.g.,petunias, phloxes and morning-glories.

Late sowings, even as late as June in the latitude of New York City, may be made of such things as China aster, sweet alyssum, California poppy (Eschscholtzia), calliopsis or coreopsis, portulaca, calendula, phlox, zinnia, marigold, candytuft, mignonette, petunia. Late- blooming beds of these and other annuals may be secured by this delayed sowing. The tendency to sow everything for early bloom deprives the garden of much freshness and interest in autumn.

The numbers of varieties in some of these long- cultivated species-groups are surprising large, and they often appeal to collectors. If a collector desires annuals for autumn display, for example, he will find that zinnias have about forty current varieties, annual pinks about fifty, petunias about sixty, pansies sixty to seventy, balsams over sixty, and stocks perhaps 300, all of which may be prolonged more or less into autumn. But the most appropriate and varied of these annuals are the China asters, which have about 450 varieties. Owing to the greater variety of everything abroad, collectors naturally send to Europe for large collections, and the very low duty on flower seeds has stimulated the collecting of annuals. Perennial flowers are more difficult to import, but many persons have recently imported fifty or more varieties of the following: gaillardia about 100 varieties, hardy chrysanthemums 100 and more, florists' pentstemons more than 150 (not sufficiently hardy), delphiniums over 200, and phlox 350. Unfortunately, collections of a single flower rarely give an artistic effect, even when at their best, owing to the difficulty of isolating troublesome colors in a garden that must be sunny, failures among highly bred varieties, the fact that the early, midseason and late sections mix poorly, and so on. The obvious limitation of gardens devoted to one kind of flower is that they are unattractive out of season, and therefore it is best to isolate them. There are practically no annuals that bloom satisfactorily throughout summer and autumn.

Background plants, for bold mass-displays of color in the rear parts of the grounds or along the borders may be secured from some of the coarser species. Good plants for such use are: sunflower and castor-bean for the back rows; zinnias for bright effects in the scarlets and lilacs; African marigolds for brilliant yellows; nicotianas for whites. Unfortunately, we have no robust growing annuals with good blues. Some of the larkspurs and the browallias are perhaps the nearest approach to them.

For lower-growing and less prominent mass-displays, the following are good: California poppies for oranges and yellows; sweet sultans for purples, whites, and pale yellows; petunias for purples, violets, and whites; larkspurs for blues and violets; bachelor's buttons (or cornflowers) for blues; calliopsis and coreopsis and calendulas for yellows; gaillardias for red-yellows and orange- reds; China asters for many colors except yellows.

For still less robustness, good mass-displays can be made with the following: alyssums and candytufts for whites; phloxes for whites and various pinks and rods; lobelias and browallias for blues; pinks for whites and various shades of pink; stocks for whites and reds; wallflowers for brown-yellows; verbenas for many colors.

Vines are abundant among the annuals, the most prominent being morning-glory, sweet pea, cobea, climbing nasturtium, Japanese hop, cypress-vine and other ipomoeas, balloon-vine, scarlet-runner, moon flowers in the South.

Some of the "everlastings" or immortelles are useful as flower-garden subjects as well as for "dry-bouquets." These "paper flowers" are always interesting to children. The colors are bright, the blooms hold long on the plant, and most of the kinds are very easy to grow. Favorite groups are the different kinds of xeranthemums and helichrysums. The globe amaranths, with clover-like heads (sometimes known as bachelor's buttons), are good old favorites. Rhodanthes and acrocliniums are also good and reliable.

Ornamental grasses should not be overlooked. They add a note to the flower-garden and to bouquets that is distinct and can be secured by no other plants. They are easily grown. Some of the good annual grasses are Agrostis nebulosa, the brizas, Bromus brizseformis, the species of eragrostis, and pennisetums and Coix Lachryma as a curiosity. Such good lawn grasses as arundo, pampas-grass, eulalias, and erianthus are perennials and therefore are not discussed here.

The amateur would do well to make up lists from the most detailed seed catalogues. The following short lists (under trade names) suggest a few things in several categories:

White-flowered annuals.

Ageratum mexicanum album.

Alyssum, common sweet.

Centranthua macrosiphon albus.

China asters.

Convolvulus major.

Dianthus, Double White Margaret.

Iberia amara; coronaría.

Ipomœa hederacea.

Lavatera alba.

Malope grandiflora alba.

Matthiola (Stocks), Cut-and- Come-Again; Dresden Perpetual; Giant Perfection; White Pearl.

Mirabilis longiflora alba.


Phlox, Dwarf Snowball; Leo- poldii.

Poppies, Flag of Truce; Shirley ; The Mikado.


Yellow- and orange-flowered annuals.

Cacalia lútea.

Calendula officinalis, common; Meteor ; sulphurea ; suffruticosa.

Calliopsis bicolor marmorata; cardaminifolia; elegans.

Cosmidium Burridgeanum.

Dimorphotheca auruntiaca.

Erynimum Perofakianum.

Eschscholtzia californica.

Hibiscus africanus; Golden Bowl.

Ipomœa coccínea lútea.

Loasa tricolor.

Tagetes, various kinds.

Thunbergia alata Fryerí ; aurantiaca.

Tropaeolum, Dwarf; Lady Bird; Tall, Schulzii.


Blue- and purple-flowered annuals.

Ageratum mexicanum; mexicanum Dwarf.

Browallia Czerniakowski ; elata.

Centaurea Cyanus, Victoria Dwarf Compact; Cyanus minor.

China asters of several varieties.

Convolvulus minor; minor unicaulis.

Gilia achilleaefolia; capitate.

Iberis umbellata; umbellate lilacina.

Kaulfussia amelloides; atroviolacea.

Lobelia Erinus.


Phlox variabilis atropurpúrea.

Salvia farinácea.


Verbena, Black-Blue; caerúlea; Golden-leaved.

Whitlavia gloxinioides.

Rose- and rose-red-flowered annuals.

Cacalia, Scarlet.

Clarkia elegant rosea.

Convolvulus tricolor roseus.

Dianthus. Half-Dwarf Early Margaret; Dwarf Perpetual chinensis.

Gaillardia picta.

Ipomoea coccínea; volubilis.

Matthiola annuus; Blood-Red Ten Weeks; grandiflora, Dwarf.

Papaver (Poppy) cardinale; Mephisto.

Phaseolus multiflorus.

Phlox, Large-flowering Dwarf; Dwarf Fire-ball; Black Warrior.

Salvia coccínea.

Saponaria. [Thumb.

Tropaeolum, Dwarf, Tom Verbena hybrida. Scarlet Défi-Zinnia, [ance.

Annuals useful for edgings of beds and walks, and for ribbon-beds.

Ageratum, blue and white Alyssum, sweet.





Dianthuses or pinks.


Gypsophila muralis.

Iberia or candytufts.


Lobelia Erinus.



Portulacas or rose moss.

Saponaria calabrica.




Late-blooming annuals.

Probably the best annuals to bloom in late fall, even after the first frosts, are petunia, phlox, and verbena. Other excellent kinds are ageratum, alyssum, antirrhinum or snapdragon, Calendula officinalis, California poppy, gaillardia, marigold, and pansy. The list may be extended by Abronia umbellata.

Adonic aestivalia; autumnale.

Argemone grandiflora.


Carduus benedictus.

Centaurea Cyanus (bachelor's button).


Centranthus macrosiphon.

Cerinthe retorta.

Cheiranthus Cheiri.


Convolvulus minor; tricolor.

Dianthus of various kinds.

Elsholtzia cristata.

Erysimum Perofsklanum; arkansanum.

Gilia achilleaefolia; capitata; laciniata; tricolor.

Iberia affinis.

Lavatera alba.

Matthiolas or stocks.

Œnothera rosea; Lamarckiana; Drummondii.

Podolepis affinis; chrysantha.

Salvia coccínea; farinácea; Hor.

Vicia Gerardii. [minum.

Virginian stocks.

Viscaría elegans; oculata; Coelirosa.

If sown early or in the fall, bachelor's button, annual gypsophila and poppy will re-seed and furnish plants for late fall bloom.

The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.

See also

This article contains a definition from the Glossary of Gardening Terms.
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