Landscaping & Nursery Information for Home Gardeners


The annual flowers are those that give their best bloom in the very year in which the seeds are sown. True annuals are those plants that complete their entire life-cycle in one season. Some of the so-called annual flowers will continue to bloom the second and third years, but the bloom is so poor and sparse after the first season that it does not pay to keep them. Some perennials may be treated as annuals by starting the seeds early; Chinese pink, pansy and snapdragon are examples.

The regular biennials may be treated practically as annuals; that is, seeds may be sown every year, and after the first year, therefore, a seasonal succession of bloom may be had. Of such are adlumia, Canterbury bell, lunaria, ipomopsis, oenothera Lamarckiana; and foxglove, valerian, and some other perennials would better be treated as biennials.

Most annuals will bloom in cooler climates 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 moon-flowers, for which the northern season is commonly too short to give good bloom unless they are started very early indoors.

If flowers of any annual are wanted extra early, the seeds should be started under cover. A greenhouse is not necessary 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.

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.

Any good garden soil is suitable for annuals. If not naturally fertile and friable, it should be made so by the application of well-rotted stable-manure or humus. The spading should be at least one foot deep. The upper six inches is then to be given a second turning to pulverize and mix it. After making the surface fine and smooth the soil should be pressed down with a board. The seed may now be sprinkled on the soil in lines or concentric circles, according to the method desired. After covering the seed, the soil should be again pressed down with a board. This promotes capillarity, by which the surface of the soil is better supplied with moisture from below. Always mark with a label the kind and position of all seed sown.

If 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 roots that may have run into the bed. If beds are made in the turf, see that they are 3 ft. or more wide, so that the grass roots will not undermine them. Against the shrub borders, this precaution may not be necessary. In fact, it is desirable that the flowers fill all the space between the overhanging branches and the sod.

It is surprising how few of the uncommon or little known annuals really have great merit for general purposes. There is nothing yet to take the place of the old-time groups, such as amaranths, zinnias, calendulas, daturas, balsams, annual pinks, candytufts, bachelor's buttons, wallflowers, larkspurs, petunias, gaillardias, snapdragons, coxcombs, lobelias, coreopsis or calliopsis, California poppies, four-o'clocks, sweet sultans, phloxes, mignonettes, scabiosas, nasturtiums, marigolds, China asters, salpiglossis, nicotianas, pansies, portulacas, castor beans, poppies, sunflowers, verbenas, stocks, alyssums, and such good old running plants as scarlet runners, sweet peas, convolvuluses, ipomeas, tall nasturtiums, balloon vines, cobeas. Of the annual vines of recent introduction, the Japanese hop has at once taken a prominent place for the covering of fences and arbors, although it has no floral beauty to recommend it.

For bold mass-displays of color in the rear parts of the grounds or along the borders, some of the coarser species are desirable. 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 gross 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.

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 reds; 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.

A garden of pleasant annual flowers is not complete that does not contain some of the "everlastings" or immortelles. These "paper flowers" are always interesting to children. They are not so desirable for the making of "dry bouquets" as for their value as a part of a garden. The colors are bright, the blooms hold long on the plant, and most of the kinds are very easy to grow. My 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.

The 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 brizæformis,_ 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 are therefore not included in this discussion.

Some of the most reliable and easily grown annuals are given in the following lists (under the common trade names).

_List of annuals by color of flowers._

White Flowers

Ageratum Mexicanum album.
Alyssum, common sweet; compacta.
Centranthus macrosiphon albus.
China asters.
Convolvulus major.
Dianthus, Double White Margaret.
Iberis amara; coronaria, White Rocket.
Ipomoea hederacea.
Lavatera alba.
Malope grandiflora alba.
Matthiola (Stocks), Cut and Come Again; Dresden Perpetual; Giant   Perfection; White Pearl.
Mirabilis longiflora alba.
Phlox, Dwarf Snowball; Leopoldii.
Poppies, Flag of Truce; Shirley; The Mikado.

Yellow and Orange Flowers

Cacalia lutea.
Calendula officinalis, common; Meteor; sulphurea; suffruticosa.
Calliopsis bicolor marmorata; cardaminefolia; elegans picta.
Cosmidium Burridgeanum.
Erysimum Perofskianum.
Eschscholtzia Californica.
Hibiscus Africanus; Golden Bowl.
Ipomoea coccinea lutea.
Loasa tricolor.
Tagetes, various kinds.
Thunbergia alata Fryeri; aurantiaca.
Tropaeolum, Dwarf, Lady Bird; Tall, Schulzi.

Blue and Purple Flowers

Ageratum Mexicanum; Mexicanum, Dwarf.
Asperula setosa azurea.
Brachycome iberidifolia.
Browallia Czerniakowski; elata.
Centaurea Cyanus, Victoria Dwarf Compact; Cyanus minor.
China asters of several varieties.
Convolvulus minor; minor unicaulis.
Gilia achilleaefolia; capitata.
Iberis umbellata; umbellata lilacina.
Kaulfussia amelloides; atroviolacea.
Lobelia Erinus; Erinus, Elegant.
Phlox variabilis atropurpurea.
Salvia farinacea.
Verbena, Black-blue; caerulea; Golden-leaved.
Whitlavia gloxinioides.

Red and Rose-red Flowers

Abromia umbellata.
Alonsoa grandiflora.
Cacalia, Scarlet.
Clarkia elegans rosea.
Convolvulus tricolor roseus.
Dianthus, Half Dwarf Early Margaret; Dwarf Perpetual; Chinensis.
Gaillardia picta.
Ipomoea coccinea; volubilis.
Matthiola annuus; Blood-red Ten Weeks; grandiflora, Dwarf.
Papaver (Poppy) cardinale; Mephisto.
Phaseolus multiflorus.
Phlox, Large-flowering Dwarf; Dwarf Fireball; Black Warrior.
Salvia coccinea.
Tropaeolum, Dwarf, Tom Thumb.
Verbena hybrida, Scarlet Defiance.

_Useful annuals for edgings of beds and, walks, and for ribbon-beds._

Ageraturn, blue and white.
Alyssum, sweet.
Dianthuses or pinks.
Gypsophila muralis.
Iberis or candytufts.
Lobelia Erinus.
Portulaca or rose moss
Saponaria Calabrica.

_Annuals that continue to bloom after frost._

This list is compiled from Bulletin 161, Cornell Experiment Station. Several hundred kinds of annuals were grown at this station in Ithaca, N.Y. The notes are given in the original trade names.

Abronia umbellata.
Adonis aestivalis; autumnale.
Argemone grandiflora.
Carduus benedictus.
Centaurea Cyanus.
Centranthus macro-
Cerinthe retorta.
Cheiranthus Cheiri.
Convolvulus minor; tricolor.
Dianthus of various kinds.
Elsholtzia cristata.
Erysimum Perofskianum; Arkansanum.
Eschscholtzias, in several varieties
Gaillardia picta.
Gilia achilleaefolia; capitata; laciniata; tricolor.
Iberis affinis.
Lavatera alba.
Matthiolas or stocks.
oenothera rosea; Lamarckiana;
Phlox Drummondii. {Drummondii.
Podolepis affinis; chrysantha.
Salvia coccinea; farinacea; Horminum.
Vicia Gerardi.
Virginian stocks.
Viscaria elegans; oculata; Coeli-rosa.

_List of annuals suitable for bedding (that is, for "mass effects" of color)._

A list of this kind is necessarily both incomplete and imperfect, because good new varieties are frequently appearing, and the taste of the gardener must be consulted. Any plants may be used, broadly speaking, for bedding; but the following list (given in terms of trade names) suggests some of the best subjects to use when beds of solid, strong color are desired.

Adonis aestivalis; autumnalis.
Ageratum Mexicanum; Mexicanum, Dwarf.
Bartonia aurea.
Calendula officinalis, in several forms; pluvialis; Pongei; sulphurea,
  fl. pl.; suffruticosa.
Calliopsis bicolor marmorata; cardaminefolia; elegans picta.
Callirrhoë involucrata; pedata; pedata nana.
Centaurea Americana; Cyanus, Victoria Dwarf Compact; Cyanus minor;
China asters.
Chrysanthemum Burridgeanum; carinatum; coronarium; tricolor.
Convolvulus minor; tricolor.
Cosmidium Burridgeanum.
Delphinium, single; double.
Dianthus, Double White Half Dwarf Margaret; Dwarf Perpetual;
  Caryophyllus semperflorens; Chinensis, double; dentosus hybridus;
  Heddewigii; imperialis; laciniatus, Salmon Queen; plumarius;
  superbus, dwarf fl. pl.; picotee.
Elsholtzia cristata.
Eschscholtzia Californica; crocea; Mandarin; tenuifolia 
Gaillardia picta; picta Lorenziana.
Gilia achilleaefolia; capitata; laciniata; linifolia; nivalis; tricolor.
Godetia Whitneyi; grandiflora maculata; rubicunda splendens.
Hibiscus Africanus; Golden Bowl.
Iberis affinis; amara; coronaria; umbellata.
Impatiens or balsam.
Lavatera alba; trimestris.
Linum grandiflorum.
Madia elegans.
Malope grandiflora.
Matricaria eximia plena.
Matthiola or stock, in many forms; Wallflower-leaved; bicornis.
Nigella, or Love-in-a-mist.
oenothera Drummondii; Lamarckiana; rosea tetraptera.
Papaver or poppy, of many kinds; cardinale; glaucum; umbrosum.
Petunia, bedding kinds.
Phlox Drummondii, in many varieties.
Salvia farinacea; Horminum; splendens.
Schizanthus papilionaceus; pinnatus.
Silene Armeria; pendula.
Tagetes, or marigold, in many forms; erecta; patula; signata.
Tropaeolum, Dwarf.
Verbena auriculaeflora; Italica striata; hybrida; caerulea; Golden-leaved.
Viscaria Coeli-rosa; elegans picta; oculata.
Zinnia, Dwarf; elegans alba; Tom Thumb; Haageana; coccinea plena

_List of annuals by height._

It is obviously impossible to make any accurate or definite list of plants in terms of their height, but the beginner may be aided by approximate measurements. The following lists are made from Bulletin 161 of the Cornell Experiment Station, which gives tabular data on many annuals grown at Ithaca, N.Y. Seeds of most of the kinds were sown in the open, rather late. "The soil varied somewhat, but it was light and well tilled, and only moderately rich." Ordinary good care was given the plants. The average height of the plants of each kind at full growth, as they stood on the ground, is given in these lists. Of course, these heights might be less or more with different soils, different treatments, and different climates; but the figures are fairly comparable among themselves.

The measurements are based on the stock supplied by leading seedsmen under the trade names here given. It is not unlikely that some of the discrepancies were due to mixture of seed or to stock being untrue to type; some of it may have been due to soil conditions. The same name may be found in two divisions in some instances, the plants having been grown from different lots of seeds. The lists will indicate to the grower what variations he may expect in any large lot of seeds.

Seedsmen's catalogues should be consulted for what the trade considers to be the proper and normal heights for the different plants.

Plants 6-8 in. high

Abronia umbellata grandiflora.
Alyssum compactum.
Callirrhoë involucrata.
Godetia, Bijou, Lady Albemarle, and Lady Satin Rose.
Gypsophila muralis.
Kaulfussia amelloides.
Leptosiphon hybridus.
Linaria Maroccana.
Lobelia Erinus and Erinus Elegant.
Nemophila atomaria, discoidalis, insignis, and maculata.
Nolana lanceolata, paradoxa, prostrata, and atriplicifolia.
Podolepis chrysantha and affinis.
Rhodanthe Manglesii.
Sedum caeruleum.
Silene pendula ruberrima.

Plants 9-12 in. high

Asperula setosa azurea.
Brachycome iberidifolia.
Calandrinia umbellata elegans.
Callirrhoë pedata nana.
Centaurea Cyanus Victoria Dwarf Compact.
Centranthus macrosiphon nanus.
Collinsia bicolor, candidissima and multicolor marmorata.
Convolvulus minor and tricolor.
Eschscholtzia crocea.
Gamolepis Tagetes.
Gilia laciniata and linifolia.
Godetia Duchess of Albany, Prince of Wales, Fairy Queen, Brilliant, grandiflora maculata, Whitneyi, Duke of Fife, rubicunda splendens.
Helipterum corymbiflorum.
Iberis affinis.
Kaulfussia amelloides atroviolacea, and a. kermesina.
Leptosiphon androsaceus and densiflorus.
Linaria bipartita splendida.
Matthiola dwarf Forcing Snowflake, Wallflower-leaved.
Mesembryanthemum crystallinum.
Mimulus cupreus.
Nemophila atomaria oculata and marginata.
Nolana atriplicifolia.
Omphalodes linifolia.
oenothera rosea and tetraptera.
Phlox, Large-flowering Dwarf and Dwarf Snowball.
Rhodanthe maculata.
Saponaria Calabrica.
Schizanthus pinnatus.
Silene Armeria and pendula.
Viscaria oculata cserulea.

Plants 13-17 in. high

Abronia umbellata.
Acroclinium album and roseum.
Brachycome iberidifolia alba.
Browallia Czerniakowski and elata.
Calandrinia grandiflora.
Calendula sulphurea flore pleno.
Chrysanthemum carinatum.
Collomia coccinea.
Convolvulus minor and minor unicaulis.
Dianthus, the Margaret varieties, Dwarf Perpetual, Caryophyllus
  semperflorens, Chinensis, dentosus hybridus, Heddewigii, imperialis,
  laciniatus, plumarius, superbus dwarf, picotee, Comtesse de Paris.
Elsholtzia cristata.
Eschscholtzia Californica, Mandarin, maritima and tenuifolia.
Gaillardia picta.
Gilia achillesefolia alba and nivalis.
Helipterum Sanfordii.
Hieracium, Bearded.
Iberis amara, coronaria Empress, coronaria White Rocket,
Sweet-scented, umbellata, umbellata carnea, and umbellata lilacina.
Leptosiphon carmineus.
Lupinus nanus, sulphureus.
Malope grandiflora.
Matthiola, Wallflower-leaved and Virginian stock.
Mirabilis alba.
oenothera Lamarckiana.
Palafoxia Hookeriana.
Papaver, Shirley and glaucum.
Phlox of many kinds.
Salvia Horminum.
Schizanthus papilionaceus.
Statice Thouini and superba.
Tagetes, Pride of the Garden and Dwarf.
Tropaeolum, many kinds of dwarf.
Venidium calendulaceum.
Verbena of several kinds.
Viscaria Coeli-rosa, elegans picta, oculata, and oculata alba.
Whitlavia gloxinioides.

Plants 18-23 in. high

Adonis aestivalis and autumnalis.
Amarantus atropurpureus.
Calendula officinalis, Meteor, suffruticosa, and pluvialis.
Calliopsis bicolor marmorata.
Callirrhoë pedata.
Centaurea Cyanus minor Blue and suaveolens.
Centranthus macrosiphon.
Chrysanthemum Burridgeanum, carinatum, tricolor Dunnettii.
Cosmidium Burridgeanum.
Delphinium (annual).
Eutoca Wrangeliana.
Gaillardia picta, Lorenziana.
Gilia achilleaefolia, a. rosea and tricolor.
Helichrysum atrosanguineum.
Ipomoea coccinea.
Linum grandiflorum.
Loasa tricolor.
Lupinus albus, hirsutus and pubescens.
Malope grandiflora alba.
Matricaria eximia plena.
Matthiola, several kinds.
oenothera Drummondii.
Papaver Mephisto, cardinale, c. hybridum, c. Danebrog, umbrosum.
Tagetes patula and signata.
Vicia Gerardii.
Whitlavia grandiflora and g. alba.
Xeranthemum album and multiflorum album.
Zinnias of many kinds (all not mentioned in other lists).

Plants 24-30 in. high

Bartonia aurea.
Calendula officinalis fl. pl., Prince of Orange and Pongei.
Calliopsis elegans picta.
Cardiospermum Halicacabum.
Carduus benedictus.
Centaurea Cyanus minor Emperor William.
Cheiranthus Cheiri.
Chrysanthemum tricolor, t. hybridum and coronarium sulphureum fl. pl.
Clarkia elegans rosea.
Datura cornucopia.
Erysimum Arkansanum and Perofskianum.
Eutoca viscida.
Gilia capitata alba.
Helichrysum bracteatum and macranthum.
Hibiscus Africanus.
Impatiens, all varieties.
Lupinus hirsutus pilosus.
Matthiola Blood-red Ten Weeks, Cut and Come Again, grandiflora,
  annuus, and others.
Mirabilis Jalapa folio variegata and longiflora alba.
Papaver, American Flag, Mikado and Double.
Perilla laciniata and Nankinensis.
Salvia farinacea.
Tagetes Eldorado, Nugget of Gold, erecta fl. pl.
Xeranthemum annuum and superbissimum fl. pl.
Zinnia elegans alba fl. pl.

Plants 31-40 in. high

Acroclinium, double rose and white.
Adonis aestivalis.
Ageratum Mexicanum album and blue.
Amarantus bicolor ruber.
Argemone grandiflora.
Centaurea Americana.
Centauridium Drummondii.
Cerinthe retorta. {c. double yellow.
Chrysanthemum coronarium album and Clarkia elegans alba fl. pl.
Cleome spinosa.
Cyclanthera pedata.
Datura fastuosa and New Golden
Euphorbia marginata. {Queen.
Gilia capitata alba.
Helianthus Dwarf double and cucu-
Hibiscus Golden Bowl. {merifolius.
Lavatera trimestris.
Madia elegans.
Martynia craniolaria.
Salvia coccinea.

Plants 41 in. and above.

Adonis autumnalis.
Helianthus of several garden kinds (not mentioned elsewhere).
Ricinus, all varieties.
And many climbing vines.

Adapted from:  Manual Of Gardening by L. H. Bailey
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