Chapter 3. Bulbs For The Rock Garden

Some of the dwarfer-growing bulbs are among the most attractive and useful subjects for the rock garden. Most of them bloom early and furnish patches of brilliant colour before the great mass of rock plants awake from their winter sleep. So, apart from their own intrinsic beauty, they well deserve their place in the rock garden.

They are very effective if planted in clumps in odd corners of the rock garden, and are especially attractive when naturalized on the grassy slopes adjacent to it. In the rock garden itself they are best planted beneath a carpeting of Accena microphylla, Arenaria balearica, Globularia nana, or some other dwarf trailer. The bulbs will flower before these break into flower, and when their bloom is over, the foliage of the rock plants will hide their decaying leaves.

A list of bulbs especially suitable for planting in the rock garden will be found below; some are also excellent for growing in the Alpine House, these are also shown below.

The generality of bulbs are of the easiest cultivation, needing but to be planted in the early autumn at about two or three times their own depth, in reasonably good and light garden soil, with which a good amount of leaf-mould has been mixed. They should be planted at a uniform depth and should not come into contact with recent manure. Good drainage is essential. If the soil is inclined to be at all heavy, it is desirable to lighten it by working in sand at and around each spot in which a clump of bulbs is to be planted, and a layer of sand round each bulb will be found beneficial. Bulbs, as a rule, should be planted deeply, rather than shallowly, especially crocuses, gladioli, and lilies, because the bulbs are then less likely to suffer from the effects of frost.

Fig. 3-Correct way of Planting a Bulb

The hole for the bulb should be scraped out with a towel.

Plant the bulbs as early in the autumn as possible, especially the spring-flowering ones; they then have ample time to develop their roots before the strain of flowering makes its demands on them. Early planting promotes larger blooms. It is advisable always to plant the bulbs with a trowel and to press them firmly, but gently, into the earth before they are covered up. Never plant bulbs with a dibber; this makes a narrow V-shaped hole in which it is difficult to set the bulb straight and in which an air-space, which will parch the roots, will be left.

Bulbs For The Rock Garden

Most bulbs, having been planted in suitable soil at a reasonable distance apart, may be allowed to remain for several years without being taken up, divided, and replanted.

Bonemeal is a good artificial manure for bulbs, and should be dusted round them at the rate of two ounces to the square yard and thoroughly forked in in February; an equal amount of superphosphate may, with advantage, be added.

Removing Withered Foliage

Fig 4 - Incorrect way of Planting a Bulb. If the bulb is planyed with a dibber, the inevitable air-space beneath the bulb will parch the roots.

No attempt should be made to remove leaves or flower-stalks until they have withered and decayed to such an extent that they may be pulled away by a very slight effort. The long sword-like leaves of crocuses, hyacinths, etc., should be neatly plaited together, to obviate untidiness of appearance, and should be allowed to remain until they are quite decayed. The dead flowers ought to be cut off just below the spike of bloom, unless it is wished to save the seed. This holds good for all bulbs that have a woody or strong flower stem.

Most bulbs remain where they are from year's end to year's end, provided that the soil is suitable, the drainage sufficient, and that they are planted deeply. (See individual cultural details in List of Plants, Chapter 12.) Bulbs have a tendency to rise to the surface, especially corms, for in the crocus and gladiolus, though not in the cyclamen, the new corms are formed every year on the top of the old ones, which perish.

Naturalizing Bulbs In Grass

Most of our spring bulbs are far more beautiful when viewed in their natural surroundings among the grass and in the meadows, woodlands, or wild garden than when planted, however naturally and artistically, in borders. Most of them, too, especially daffodils, crocuses, and scillas, do much better in this natural state than in beds or borders where they are constantly being disturbed.

Do not plant them on lawns, as the grass cannot be cut until the leaves of the bulbs have turned yellow and dried up. Another word of caution: do not plant daffodils in pastureland, as they are poisonous to cattle.

The bulbs are best planted in long, narrow, oval strips some thirty to forty feet in length, shaped like patches of snow driven by the wind into long slender drifts on the ground. They should be scattered on the grass over an area shaped as above, so that they lie thicker towards the center of the "drift," and should be planted with a trowel or bulb planter just where they fall. There should be no regular, well-defined margin to the "drift," the edges should be indistinct and gradually merging into the grass.

August and September is the best planting time; smaller bulbs like the crocus and scilla should be set some three inches apart, while daffodil bulbs should have about ten inches between them. Bulbs that have been used for beds and borders are equally as good as new bulbs for naturalizing in grass and should be replanted immediately after being lifted from the beds and while their foliage is still green.

Some seven years, at least, may be allowed to elapse before it is necessary to disturb naturalized bulbs, provided they receive an annual top-dressing of leaf-mould each autumn.

Bulbs In Pots Or Pans

Some of the dwarfer-growing bulbs are among the most charming subjects for the Alpine House. The bulbs should be planted in autumn and the crowns should just appear above the surface of the soil, which should come up to within three quarters of an inch of the top of the pot or pan. After planting, the pots or pans should be well soaked in water and placed in the open on boards or slates so that worms cannot get up into the soil. The pots or pans should be surrounded and covered with a layer of five inches of fibre, sand or ashes, and left for seven to nine weeks until the roots will have formed and the tops have made an inch of growth, when they may be moved to a frame or a cold house, if the roots have made sufficient growth, they should be liberally supplied with water, but not saturated. The less forward plants should be put back in the ashes, and will furnish a succession of later bloom, if brought into the Alpine House at successive intervals. The darkness encourages growth of the roots, which is so essential to good blooms.

The pots or pans should not be subjected to full light until two or three days after the covering of fibre has been removed: that is, until the pale yellow shoots have turned green. When this has happened, the pots or pans should be placed close to the glass and should be brought on gradually till the flower buds are well advanced, when liquid manure-water may be used. A good potting compost consists of a mixture of equal parts of loam, leaf-mould, sand, and well-rotted cow-manure.

As to the number of bulbs that may be planted in a pot or pan: this, of course, depends on the species of bulb and on the size of pot used. Snowdrops, crocuses, and scillas may be planted so that they practically touch, that is, about nine bulbs in a five-inch pot; larger bulbs, such as the smaller daffodils, may be planted six in a five-inch pot; while only three hyacinths should be grown in a six-inch pot.

Some Bulbs and Tubers for the Rock Garden

Allium azureum, A. cyaneum, A.

Moly, and A. neapolitanum Anemone (tuberous)

Bulbocodium vernum

Chionodoxa in variety

Colchicum autumnale and C. montanum, and others

Crocus (various) Cyclamen coum, C. europaeum, C. neapolitanum (various) Eranthis hyemalis, E. cilicica

Fritillaria (various)

Galanthus (Snowdrop)

Hyacinthus azureus

Iris (various)

Leucojum asstivum and L. vernum

Muscari azureum and M. conicum

Narcissus Bulbocodium, N. cyclamineus, N. minor and N. triandrus (various) Puschkinia scilloides

Scilla bifolia, S. sibirica, and S. verna

Some Bulbs For The Alpine House

Chionodoxa Luciliae, C. sardensis

Crocus (various)

Cyclamen coum, C. ibericum, and C. neapolitanum Fritillaria (various) Hyacinthus amethystinus Iris (various) Muscari azureum and various others Narcissus asturiensis, N. Bulbocodium, N. cyclamineus, and N. triandrus Scilla (various)

Tulipa Clusiana, T. montana, T. persica, and T. sylvestris

Bulbs and Tubers for Naturalizing in Grass

Allium Moly

Anemone apennina

Chionodoxa (various)

Colchicum autumnale and C. montanum (Autumn Crocus) Crocus (various)

Fritillaria (various)

Galanthus (Snowdrop)

Hyacinthus azureus

Leucojum aestivum and vernum

Muscari conicum

Narcissus (various)

Ornithogalum

Scilla bifolia, S. sibirica, and S. verna

For Individual Cultural Details, Colour, Time of Flowering, and Height, see Alphabetical List of Plants.

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