The Wonderful World of Forcing Bulbs

Using easy-to-follow instructions, bulbs can be grown indoors and coaxed into flowering to brighten up your winter scenery. You may also have a unique set of gardening requirements – maybe you desire a continuum of color throughout the blooming season, or your yard is susceptible to pests, etc.

Remember one key point – you can do no wrong! Gardening with bulbs is easy and the more you experiment, the better you will get! Gardening for many is a loved and cherished pastime allowing a chance at creativity and needed relaxation. Planting flower seeds to vegetable seeds in container gardens, backyard gardens, hanging baskets, butterfly gardens, rock gardens and window boxes also adds beauty to our homes, yards, businesses, parks and streets.

Spring is both an exciting and refreshing time of year made even more magic with the appearance of flowers peaking up through the soil or light snow. Flower bulb varieties found in free seed catalogs, garden centers and nurseries are favorite flowers for many gardening enthusiasts, there are however some who just can’t wait until spring to enjoy the lovely flowers.

With that said there is a technique know as forcing bulbs that allows us to appreciate flower bulbs at other times of the year. To force bulbs you will want to start 15-16 weeks before bulbs should bloom (for Christmas gifts start in September), choose a pot at least twice as tall as bulbs, mix bulb fertilizer into potting soil, fill pot with light potting soil, place bulbs on top of soil close together but not touching each other or pot, sprinkle soil around bulbs, water soil and keep moist.

Next you will want to place in dark cold place (refrigerator) as bulbs will need approximately 12 weeks of cold storage and lastly when stems are about 2” tall move your pot to sunny spot to bloom. There is no reason your flower bulbs, flower and vegetable seeds cannot be enjoyed all year long.

How to Force a Bulb to Grow Indoors

Forcing, or tricking, a bulb to grow out of season and thus indoors, can add to your year round enjoyment. The most commonly used varieties for this purpose are amaryllis, paperwhites (narcissus), and hyacinths, but others are possible. Our pre-packaged kits are available to purchase, but you can do-it-yourself by following this step-by-step process:

Step 1: Choose a clean pot with drainage holes. Line the bottom with a good quality potting soil.

Step 2: Place either one large or several small bulbs in pot, allowing for a gap of about 1″ around edge. Most bulbs barely need covering. Water thoroughly. It’s advisable to stick to one variety per container and we suggest you label it with the name, planting date, and date you should bring it out of storage.

Step 3: Store your planting in a cool, dark location. Temperatures should be about 40-50° F. Leave the pots for at least 12 weeks or until the sprouts have grown to about 2″ high.

Step 4: Now the “forcing” of blooms begins! Bring the pots into warmth and light gradually. Keep them for a week in indirect sunlight and when the shoots are 4-6″ tall, move them into direct sunlight. Most bulbs will require about 2-3 weeks to bloom.


  • You can re-plant your forced bulbs outdoors when spring arrives. This is not always successful, but with some special treatment, you can get more years of growth from the bulb. The roots should be minimally disturbed, the use of fertilizer is necessary, and they may not produce the best blooms until they have “re-covered” from their interrupted life cycle.
  • Crocus and hyacinth can be forced to grow roots and bloom in water only – without any soil. Specially designed jars are available for this process. It is important to note that bulbs forced this way cannot replenish themselves and will not bloom again.
  • Moving the plant in relation to the sun will vary the blooming period. In the sun a bloom will grow quickly – by moving it to a cooler location you can retard both the bloom growth and the length of time it will last once fully developed.
  • Store your purchased bulbs in a fridge if you are not ready to pot them. Take care not to keep them near fruit – fruit emits a gas that can destroy bulbs.


Tulips need at least 15 weeks of cold to force well. Plant them with their flat side toward the rim of the pot so that the largest leaf will arch out over it. Bring them into a light, cool room until the leaves are up 4 inches and the buds are visible. Growth can be slowed by a cool environment or sped up by a warmer one. Plant bulbs in October to bloom in January, or slow them down to bloom later. After forcing, tulips are usually thrown away, as they do not recover well.


Daffodils need at least 12 weeks of cold. Pot bulbs in mid-October for blooms in January or February. Bring the pots into a light, cool room until the leaves are 3 inches tall and the buds are visible. If you want to replant the bulbs after they bloom, remove the flower stems, set the pots outdoors in a sunny, cool spot, and gradually reduce watering until the leaves die. Store the dormant bulbs in a dry airy spot at 60-70 degrees until it is time to replant them in the fall. These bulbs won’t produce well for a year or two.

Dutch Iris

Dutch iris bulbs require 8-10 weeks of 40-50 degree temperatures. They can be stored in the refrigerator for this period and them potted, but the bulbs must be kept dry. For top growth development they need temperatures of 55-65 degrees. Bring them out for display when they bloom; they should last about two weeks. Then set the pots outside (but above40 degrees since they are not acclimatized) for later planting.