Question: I love seeing amaryllis at Christmas time. Can other bulbs be “forced”? Can you do it any time of the year?
Answer: Yes, there are many more types of bulbs that can be forced and, yes, you can do it anytime you desire a beautiful burst of color in your home. Try also in the garden for a continuous succession of blooms.
To do this you must simulate the conditions that the bulbs need in order to bloom — known as the cooling period. In other words, you are tricking the bulbs into thinking that the cold winter is over, it is now spring and it is time to bloom. Amaryllis and paperwhite narcissus are both native to a warm climate so they do not require a cooling period in order to bloom.
Since not all bulbs bloom well indoors, I have listed the names of some of the bulbs that are usually the most successful for forcing. These all need between eight to 16 weeks to chill. Whatever bulb you select will have more precise instructions included.
The following is a general but incomplete list of bulbs that bloom successfully indoors: Siberian Squill (Scilla siberica), Snowdrops (Galanthus nivalis), Bulbous iris (Iris reticulata), Grape hyacinth (Muscari armeniacum), Dutch crocus, checkered lily (Fritillaria meleagrus), daffodil, tulip and the Dutch hyacinth (Hyacinthus orientalis). As always, examine for quality, size, firmness and overall health.
Your next decision will be the medium to use. Water or soil? If you want to force your bulbs in water for display inside the house, there are containers that are made especially for this. They are shaped so that the bulb is kept out of the water while the roots below are immersed in water.
Most bulbs do better in soil. For those, combine potting mix and water until you have a moist, but not soggy, mixture. Fill your containers until almost 2/3 full. Place the bulbs in the containers with the roots facing down. When forcing bulbs, whether in water or soil, place the bulbs closer than you would do in your garden. They should be close to touching but not quite — this makes for a spectacular display. Cover with more potting soil, leaving just the tips of large bulbs exposed. The small bulbs should be covered completely with soil to a depth of not more than ½ inch.
Find a safe, out-of-the-way place to put your bulbs. Some places to consider are a garage, cellar, unheated basement, outside or anywhere that the temperature is between 35-55 degrees. Some people use a refrigerator, but do not put bulbs in the refrigerator with fruit. If you choose to put the bulbs outside, be aware that some bulbs (the non-poisonous ones) are delicious treats for outdoor critters. Protect them with leaves or other mulches, tarps, boards or wiring. Guard against them becoming too moist or too dry.
Check periodically for signs of rooting. Roots will usually poke out the bottoms of pots. Judge their readiness by the appearance of roots, not the growth from the top. Roots are of prime importance. Strong, vigorous roots ensure proper flowering.
Forcing bulbs allows you to enjoy them longer, and timing the bloom times will produce a continuous, showy display of color. However, be aware that after forcing bulbs, it can take up two years for them to bloom again, if they bloom again at all.