Home › Bulb Culture › Bulb Culture: Bulbs

Bulb Culture: Bulbs

DEPTH FOR PLANTING BULBS. Unless a bed of bulbs is planted at uniform depth they will not bloom uniformly. It is a good practice to exca vate a bed to a given depth, place the bulbs as desired over the bottom, and then cover all to the same depth, thus making certain that they are evenly planted. The larger and stronger bulbs are, the deeper they may be planted. They may be planted deeper in sandy soil than in heavy clay soil. A general rule for planting depth is three times the average diameter of the bulb. Bulbs are frequently planted too shallow. For depths at which to plant bulbs, also distances apart, see "Bulb Table" (Plate IX, Page 46). When planted in holes made with a dibble, put loose dirt or sand in the bottom of the hole to avoid air space. Planting with trowel or dibble, however, should not be done where uniform show beds are desired. For lawns, bulbs may be dibbled in, but it is better to cut the sod and press back after planting. This is done in the fall when lawns are soft from rains.

MULCHING BULBS. Bulbs lie dormant, to all appearances, over winter, and should be thoroughly mulched to insure that they do not start to grow in any unseasonable warm spell of weather, and also in order to prevent heaving. Mulch with straw or leaves to a depth of four inches to six inches, but do not add this mulch too early; wait till a fairly thick crust has been frozen over the ground. Lilies always require heavy protection and will succeed better in partial shade. Remove the mulch or litter in spring before warm weather and after damage from freezing is past. The coarse part of the mulch should be picked off carefully, care being taken not to injure the tops of the bulbs. The finer pieces of mulch may be worked into the soil, if the cultivating is done cautiously.

REPRODUCTION OF BULBS. Many bulbs, like the varieties of crocus and certain varieties of narcissi, will continue to multiply by developing small bulblets and in that way produce a flower effect for a considerable number of years. Other bulbs, like certain varieties of the tulips and other varieties of narcissi, will have their energy sapped during the first one or two years. They will not reproduce bulblets and the result is that in order to continue the flower effect new bulbs must be purchased and planted in their place at the end of two or three years. Spanish iris and also the English iris will, under ideal conditions of soil and cultivation, continue to develop new bulbs and to multiply. For this reason they can be left in the ground during a number of years. In cutting flowers from bulbs it is quite necessary that some leaf surface should remain after the flower stalk has been removed. This leaf surface provides a "stomach" for the plant, in which digestive functions continue and new food is supplied to the bulb for the purpose of enlarging it and for the purpose of forming new bulblets. The gladiolus is the best example of bulbs which are reproduced in the average garden by new bulblets. Many varieties of gladioli, however, will not reproduce bulblets if the flowers are removed. None of the varieties of the gladiolus will produce new bulblets or make strong bulbs if, when the flowers are cut, all of the leaves are removed.

TREATMENT OF BULBS AFTER FLOWERING. Bulbs will not ripen if the tops are cut very soon after flowering. For best results, do not remove the tops before late June, or until leaves turn brown. When cutting flowers cut as few leaves as possible, and do not cut the entire stem of a lily. Never lift any bulbs, if it is possible to wait, before the tops are brown and limp. If bulbs must be removed to make way for other plants, take roots, top and all-some soil also with the roots. Heel-in, not too close together, in a shady spot until the tops commence to die. Autumn-flowering bulbs also should be allowed to ripen before removal for winter storage. Oftentimes it becomes necessary in the renovating of the flower garden to dig up bulbs during the month of September or October. This is not desirable. Wherever it is foreseen that the soil in the flower beds must be spaded over and refertilized in the fall, all bulbs should be removed in the late spring and stored in the usual manner in a cool, dry, dark place in the cellar or shed until time to plant them in the fall. If it is necessary to dig up bulbs in the fall after some root growth has started, then these bulbs should be taken up with some soil attached to the roots. They should be kept moist and replanted just as soon as practical. They should never be left to dry out because after the root growth has once started this drying out of the roots is likely to cause considerable injury to the bulbs. Only such permanent sorts as the tulips, especially the Darwins, narcissi, and the lilies will as a rule repay the trouble entailed. Hyacinths seldom can be depended upon for good bloom after the first display, in any event, and are thus hardly worth the trouble of replanting. In the eastern states and in the Middle West root growth in bulbs hardly ever starts before the latter part of September because the dry months of late summer keep the bulbs dormant until the fall rains. When replanting of bulbs is done after September 15th, a good mulch of straw manure put on to keep the frost out of the ground as long as possible is essential.

Of lilies, in the case of the foreign and the hybridized, it is practically useless, in general, to try to prolong life and to improve bloom from year to year by taking the bulbs up annually. Careful study and experimenting are necessary to determine what kinds it is best to plant. The tiger lily, the speciosum, white and pink-dotted, and the madonna lily are managed easily and the native lilies are apt to be permanent, if given their natural conditions. The one named last should be planted early in the autumn or even late in the summer, not more than two or three inches deep and in heavy or somewhat clayey soil. The bulbs of this and of the others named here may be taken up every few years, as they increase in number, and be replanted in fresh soil. The bulbs of nearly all lilies except notably the madonna may be kept over winter packed in moss or sand and stored in a cool place where they will not freeze. Then they can be successfully planted in the spring (Consult XXXIII-F, Page 253). Narcissi are best left undisturbed for several years. It is best to allow crocuses and early tulips to run out, unless the tulips are wanted for formal effects. All tulips, like hyacinths, yield most satisfactory bloom if they are taken up annually and replanted at the proper season. Only the larger bulbs should be planted, where uniformity of effect is desired, while the smaller ones may be planted apart by themselves to increase in size. Late tulips often do very well undisturbed for three, four, or five years.

Crocuses, squills, and narcissi may be naturalized, especially if care is taken not to cut the tops too closely or too soon after blooming. This is one of the strong arguments in favour of planting crocus bulbs in September. The tops will have then matured before spring mowing begins.

After the bulbs of any kind have been lifted, and the tops are dried, these tops should be carefully trimmed off and the bulbs stored in a dark, cool place until time for replanting.

Plant bulbs in combinations as shown under "Bulbs." Learn which are late flowering and which are early; also which varieties are tall and which are short. Choose lilies that are easy to grow and select varieties that have proved successful.

FORCING BULBS. Bulbs are grown extensively, both privately and commercially, for cut flowers, and for indoor use during the winter season. It is not hard to achieve success in forcing bulbs if two important rules are observed, namely: I. Procure the strongest and best bulbs possible, for good care will improve the quality of the flowers but not the quantity. The latter is always fixed within the bulb before it is purchased. 2. Perfect root development must be insured before the tops are permitted to start growth. The bulbs should be planted as soon as they are procurable, with late August and November as limits. The soil to use should be rich loam mixed with bone meal in a one to fifty proportion. If the soil is heavy add leaf mold or sand. It is better to avoid manure unless it is thoroughly rotted and pulverized. Five-inch pots may be used for larger bulbs, such as hyacinths; and a three or four-inch pot for one tulip or any bulb other than a hyacinth bulb of large size. It is better, however, to plant three or more bulbs in a larger pot, as soil moisture and temperature are more evenly maintained. When being forced for cut flowers, bulbs are planted in boxes or flats of a depth of three inches to four inches, with the bulbs set from one inch to two inches apart. This is a good way to grow bulbs for decoration also, since the flats can be covered with crepe paper, raffia mats, etc., when the flowers are in bloom. Broken pottery or charcoal should be put in the bottom of the pots for drainage. The soil is then sifted into the pot or flat, but not packed, and the bulb is so planted that the top is just below the surface. Do not press the bulbs down. After planting, water thoroughly to settle the soil firmly about the bulb and do not water again until the top growth starts unless the pots or flats are stored in a place where they will dry out.