I have found that the tulip enjoys a rather heavier soil than most bulbs – this in no way means a sticky, badly drained soil, but one which may be described as a well-drained heavy loam. Some sand or grit and a small quantity of peat or very well-rotted manure will give it the necessary aid to good. Where growing for profit in the open, earliness will be assisted by a lightening of the soil and peat, sand and some cow manure should be worked in. Should the soil be of a sandy nature, peat or mould and some rotted manure will increase the humus and moisture content of the soil.
As tulips do not grow well in soil that has continually been used for tulips, the ground should first be deeply worked, bringing up to the surface the lower soil and it is to this that is added the various humus-forming ingredients. Tulips often being grown in large unheated houses and frames, the beds will require much the same attention, but must be given ample water before the bulbs are planted in November. Where it can be obtained, a quantity of wood ash is most beneficial to tulips or a 1-oz. per square yard dressing of sulphate of potash will be of equal value.
PLANTING IN OPEN GROUND
Tulips are unlike narcissus in that they should be given individual attention as to times of planting and correct depths. Many varieties seem to grow better from early November planting, yet the well-known Inglescombe Yellow and Golden Harvest both prefer to be planted in early October. Soil depths vary too, William Copeland and William Pitt, both Darwin tulips, are quite happy in a soil depth of no more than 3 in., the cherry red King George V. likes 4 in. of soil over it and the bulb of larger proportions, Farncombe Sanders, a grand cold-house tulip, likes a 5 in. covering, while I have heard it said by some growers that they plant it almost 8 in. deep. As a general rule 4 in. seems to suit most varieties, an inch deeper in light soil, an inch shallower in clay soil.
In the warmer parts of Britain where Tulip Fire disease occasionally makes its presence felt, the bulbs may be planted as late as early December, and it is said that deeper planting will help to keep the trouble at a minimum. Always plant with a wide trowel so that no air pocket is left beneath the bulb. They may be spaced 6 in. apart. When growing for, the beds should be planted 5 ft. wide with a path down either side to allow for ease in cutting.
An 11 cm. Size bulb will give a bloom of top size for outdoor planting, though for commercial cutting outdoors a 10 cm. bulb is frequently used, the cost being about 20% less for the 11 cm. Size, though of course the varieties of more recent introduction are more expensive.
Tulips bruise easily and care should be taken in handling the bulbs. The bulbs should be firm and clean, with the skin a bright brown colour. They should not be exposed to the elements at planting-time more than is necessary. After planting the top soil should be raked over to leave a bed with a fine tilth. Planting late in autumn will mean that very little attention will be given the beds, possibly nothing more than hoeing between the bulbs in spring when growth may be seen.
GROWING TULIPS UNDER CLOCHES
Cloche and cold-frame cultivation calls for some care in planting distances. Here, the bulb may be set only 4 in. apart and in rows of the same distance, a barn-type cloche taking three rows. Late November planting is preferable for cloche work, for the plant should not become too tall too soon. If it is necessary to remove the cloches whilst the weather is still cold, the cloches will have lost much of their value for uncovered plants will have almost caught up with those that began under glass.
My own method of growing under cloches is to take out a trench 8 in. deep and into the bottom 4-5 in. is worked some sand, peat and a little rottted manure. Into this the bulbs are planted, a depth of 3-4 in. being left above the-level in the trench to allow for extra room before the cloches are removed. The bulbs are covered in early February after they have been exposed to some winter weather. They then make rapid growth in the early spring sunshine and protected from frost and cold winds. The glass is removed early in April to a plantation of early strawberries.
Very tall-growing varieties should not be used for frame or cloche cultivation, a suitable selection of Darwin and Cottage types, all of which do well under glass, and which grow less than a ft. tall being:
- Charles Needham (3 in. November). Vermilion-scarlet. Clara Butt (4 in. November). Salmon pink.
- Gloria Swanson (3 in. October). Carmine with blue base. Golden Age (3 in. November). Deep golden yellow.
- New Orleans (4 in. November). Rich heliotrope.
- Peter de Hoogh (3 in. October). Rosy red, edged salmon and grows to a height of only 18 in.
- Utopia (3 in. October) Cherry red.
- Albino (3 in. November). Purest white.
- Inglescombe Yellow (4 in. October). Rich canary yellow. Marietta (4 in. November). Satin-rose. Lily-shaped bloom. Orange King (3 in. November). Orange, shaded bronze.
- Rosy Wings (3 in. November). Apricot pink and very dwarf. (Correct planting depths and month given after each variety.)
CARE OF THE BULBS AFTER FLOWERING
If tulips are allowed to remain in the ground after they have finished flowering, they will deteriorate to a point where only a tiny, short-stemmed bloom will be seen, but many of the bulbs will be suitable for a second season’s flowering if carefully lifted in early June and if not allowed to setafter flowering. Those who grow tulips for the sale of the bulbs in Lincolnshire and in Holland remove the flower-head immediately it shows colour so that the energies of the plant can be directed entirely to its bulb. Again this is where the tulip differs from the daffodil.
A garden fork should be used to lift the bulbs which should first have had the flower heads removed as soon as the petals begin to fade. A trench 6 in. deep should be made in a spare piece of ground, which has been enriched with some rotted manure. At the bottom of the trench should be placed some sand and peat and on to this the bulbs are placed with their foliage exposed and covered with soil. As it is desired to dry off the bulbs as soon as possible, all excess moisture should be withheld. As soon as the foliage has turned brown, the bulbs should be lifted, cleaned, and the foliage removed. They should be sorted for any decayed bulbs and all healthy offsets should be removed for later planting and growing on. The bulbs should be stored in a cool, dry room or shed until ready for planting again in late autumn. My own method when planting in beds about the home is to commence with say a hundred bulbs of a variety and to select the best fifty for planting again the following year. To these are added another fifty fresh bulbs and the same procedure is carried out the following year. After three years, the whole lot are scrapped and a fresh start made. In this way a high standard is maintained and at a reasonable cost.
PROPAGATING THE OFFSETS
The tiny bulblets which should first be examined for any form of disease should be planted in prepared beds in aof full sun in early September. Plenty of sand and peat is essential to the bulbs making growth and they must never be allowed to suffer from lack of moisture. Planted 3 in. apart and 3 in. deep, they will remain in the nursery beds 2+ years and should be fed regularly with liquid manure water. The flower buds must be removed when formed so that the energy of the plant is conserved for the bulb. They may then be lifted in the normal way and replanted in beds where they are to bloom.