Chilling & forcing flower bulbs

Speeding up the season – chilling and forcing flower bulbs 

Forcing refers to tricking bulbs to bloom out of season indoors by providing them with favorable conditions for growing. Plant bulbs, such as paper white narcissus and amaryllis, indoors now, and you can impress your friends and family with stunning, often fragrant indoor blooms in the months ahead. What is the cooling period for flower bulbs?

CHOOSE A PLANTING METHOD

PLANT BULBS

Place water-forced bulbs tip-end up, positioned with the bottom of the bulb 1/8 to 1/4 of an inch above the surface of the water. Roots will reach into the water.² Hyacinth, amaryllis and narcissus respond well to this method of forcing.

For other bulb types, it is best to force using gravel or potting soil. Plant bulbs about an inch apart, tip-end up, leaving 1/2 to 2/3 of the bulb exposed. If you cover the entire bulb, it may rot. After planting, water until the soil or planting medium is moist but not soggy.

CHILL TO INITIATE BLOOMING

Place water-forced bulbs tip-end up, positioned with the bottom of the bulb 1/8 to 1/4 of an inch above the surface of the water. Roots will reach into the water.² Hyacinth, amaryllis and narcissus respond well to this method of forcing.

For other bulb types, it is best to force using gravel or potting soil. Plant bulbs about an inch apart, tip-end up, leaving 1/2 to 2/3 of the bulb exposed. If you cover the entire bulb, it may rot. After planting, water until the soil or planting medium is moist but not soggy.

CHILL TO INITIATE BLOOMING

Except for amaryllis and paper white narcissus, bulbs require a period of chilling after planting in order to initiate blooming. Place the planted bulbs in a location with temperatures of 35 to 55 degrees Fahrenheit. Good locations include a root cellar, unheated garage, attic, shed or, if space allows, a refrigerator.³ If temperatures are cold enough, you can also chill the bulbs outdoors. Just make sure the soil or planting medium doesn't become overly moist.

Plant roots form and stems lengthen during this cooling period, which generally ranges from 10 to 15 weeks. If the bulbs were chilled by the bulb company prior to selling (refer to the packaging), the cooling period will be shorter. Consult the chart above for chilling time periods. Subtract any pre-chilling time, including any time spent in a refrigerator prior to planting.

During the chilling period, check on the bulbs periodically, and water when the top inch of soil or gravel becomes dry or when the water level in the jar is more than 1/2 an inch below the bottom of the bulb

Anemone: 8-10 weeks

Crocus: 8-10 weeks

Leucojum: 8-10 weeks

Chionodoxa: 10-12 weeks

Snowdrops: 10-12 weeks

Dwarf Irises: 10-12 weeks

Siberian Squill : 10-12 weeks

Hyacinths: 10-12 weeks

Tulips: 12-16 weeks

Daffodils: 10-14 weeks