Choosing Winter Flowering Bulbs
Early bulbs can bring added colour to your home in winter. Order them in early autumn (August), to plant in bowls or pots indoors or in the greenhouse in mid autumn (September).
Bulbs,that are generally grown in pots for early flowering are hyacinths, (narcissi), tulips, crocuses and cyclamen.
Choosing your bulbs
Always buy top-size bulbs for flowering indoors; you will get more and better blooms from these, and they are well worth the small extra cost. Top-size daffodils will have two or three ‘noses’ or growing points per bulb. Hyacinths are measured by their circumference, in centimetres, around the widest part of the bulb, and the top-size variety measure approximately 18-19cm (7 – 7-½ in). ‘Prepared’ hyacinth bulbs, which give blooms about mid winter (December) are usually 16-17cm (6 – 6-½ in) in circumference.
These ‘prepared’ bulbs grow much more quickly than untreated bulbs and flower in time for Christmas in Britain. The bulbs are refrigerated by the suppliers, a process that speeds up the period before flowering, but you must plant them as soon as possible after purchase. If not, the effect will wear off and they will then bloom later – probably in late winter (January).
Top-size tulips can also be recommended for planting in bowls: these measure about 12-14cm (4-½ – 5-½ in) in circumference. Crocuses should be no smaller than 7-9cm (2-½ – 3-½ in) round.
Inspect the bulbs before you buy them – or immediately upon receipt if you are buying from a mail order firm – to ensure that they are not soft or infected with mould. Bulbs should feel firm to the touch and quite heavy in relation to their size. Bulbs that feel soft or very light are undoubtedly rotting inside and will neither flower nor grow properly.
There are many varieties of hyacinths, daffodils, tulips and crocuses — choose those that appeal to you. The Roman hyacinths are the earliest to come into flower, apart from the treated varieties. The narcissi varieties Paper White and Grand Soleil d’Or are extremely attractive for indoor planting arrangements, and the large-flowered Dutch crocuses, together with dwarf early single and double tulips can also be highly recommended for winter flowering in the home.
Materials for planting
You can buy special bowls for bulbs from garden centres and shops. The usual growing medium to use with these is bulb fibre, also easily obtainable from your garden suppliers. This is basically peat combined with a mixture of crushed charcoal and oyster shell. You can also grow your bulbs in ordinary plastic or clay flowerpots, provided you first cover theholes with a layer of crocks topped with a thin layer of roughage. Use a conventional potting compost in pots, such as J.I. No 1, or a loamless (soilless) compost. They must be moist before use.
How to plant
Now to the method of planting the bulbs. First place a layer of fibre or compost in the bottom of the container and firm it lightly with your fingers. Then stand the bulbs on the growing medium, ensuring that their tips are level, or Just above, the rim of the container. Then place the compost or fibre between and around them and lightly firm it with your fingers. After planting, the upper third of hyacinth bulbs should remain exposed and the noses of daffodils and crocuses must be visible. Plant your bulbs close together for the best flower display but do not let them touch each other. For example a 15cm (6 in) diameter bowl will hold two or three hyacinths, one daffodil, five tulips, or eight crocuses; and a 30cm (12 in) diameter bowl will contain seven to nine hyacinths, six to seven daffodils, twelve tulips or sixteen crocuses. These estimates are for top-sized bulbs.
Caring for your bulbs
After planting, place the bowls in complete darkness in a cool place — a cellar is ideal. Many people bury the bowls about 15cm (6 in) deep in a bed of ashes or sand in a cool part of the garden. Or you can put each container into a black polythene bag and place it in a cool, shady part of the garden. Try to keep the temperature below 9°C (48°F) at this stage.
Leave the bulbs in these conditions for a period of six to eight weeks (during which time roots will develop) until they start to produce shoots. Daffodils, hyacinths and tulips should be brought back into the light when their shoots are 2-3cm (1 in) long, and crocuses when they have 13mm (I in) high shoots.
To start with, place the bowls in subdued light, then, after a week, transfer them to full light and a temperature of 10°C (50°F). The temperature should not be higher than this until the flower-buds are well formed, at which time you can increase the temperature to 15°C (60°F).
Keep the compost or fibre moist at all times. Do not over-water bowls; remember that they have no drainage holes in the base, and so the fibre could become saturated. If this should happen, carefully stand the bowl on its side until the surplus water has drained away.
It should not be necessary to stake the flower-stems but if these do become top heavy, insert two or three canes and encircle them.
When the bulbs have finished flowering, stand them in a cold frame or a sheltered spot out of doors to complete their growth. Water and feed them until the leaves have completely died down. Then remove the bulbs, clean and dry them and store in a cool dry place until planting time in the autumn. You must not grow them indoors again, but you can plant them in the garden where they will make a good display during spring of the following year.