'Force' your spring bulbs now to enjoy next year
Now is the time to "force" into bloom tulips, daffodils, grape hyacinths and other hardy bulbs you had chillin' for the past few months, according to local horticultural experts. This inside gardening replicates what will eventually happen outdoors in a couple of months when the spring bulbs planted in flower beds last fall start blossoming as the weather warms up for good.
Dorthe Hviid of Berkshire Botanical Garden in Stockbridge, Mass., says forcing bulbs to flower indoors ahead of their natural schedule, in time for Easter perhaps, can be daunting for novices, but colorful in the end.
"Once you've tried it, I think you'll agree that it's well worth the effort and truly a magical experience," she said.
If you adhere to the following steps, expect very good results, says Darren Godette, head grower at Mettowee Mill Garden Center in Dorset, Vt.
"They all should flower in the first season," he said.
Forcing the issue with bulbs began late last fall, but if you didn't get the memo on this step, bulbs already in forced mode are available at local nurseries or online, ready to start the blooming process.
Unforced bulbs should have been chilled in a dark space, such as an unheated basement or a refrigerator at a temperature between 35 to 45 degrees. Plant the bulbs in pots close to each other without touching, leaving the tops of the bulbs exposed. Hviid says clay pots work best as they absorb the water to prevent soggy soil.
"Tulips and daffodils need 16 weeks to cool, snowdrops and crocus need 12 weeks," she said.
Choose plants with varied growing cycles to ensure continuous indoor blooms.
"Some [bulbs] grow fast, some grow slow, so stagger your color so you'll have flowers throughout the spring," Godette said.
When shopping for bulbs, Hviid says choose good-quality, top-sized bulbs.
"The bigger the bulb, the bigger the flower," she said. "Crocus are among the easiest [to force], but they don't last long, maybe a week."
The warm up
Once roots show through the hole of the pot and growth emerges from the top of the bulb, move the chilled pot bulbs to the coolest room in the house that gets plenty of natural light. Close any heat vents and the door to keep the room at about 50-60 degrees for about a week or until the shoots expand.
Next, relocate to a warmer room for a full bloom. In all, most bulbs take three to four weeks to bloom after being taken out of cold storage.
"Keep back from the window on warm days and in medium to bright light," Hviid noted. "To prolong the bloom, place the pots in a cooler room at night."
Watering depends on the size of the pot, but horticulturists recommend every other day, more often in warmer-than-normal weather to prevent drying out.
"Bulbs can rot if they are too wet," Godette said. "If you plan to eventually put the bulbs in a garden, keep feeding them fertilizer high in phosphorus.
To prolong the blooms, Hviid suggests placing the plants in a cooler room at night.
After the Bloom
As the flowers start to wilt and discolor, resist the urge to clip off the bloom.
"Don't cut down to the bulb, let the plant die down natural," Godette said. "Leave the foliage to allow for photosynthesis to store energy in the bulb for next year."
Following the die-off, replant the bulbs outside for next spring, or bag them up in paper or burlap and put in a cool dry place until the next forced cycle begins in the fall.
What: "Out of Africa: Discovering South African bulbs among New England Springtime favorites." Fitzpatrick Greenhouse is a harbinger of spring through March 17 when the public is invited to enjoy nearly 100 flowering bulbs in this exhibition. Exhibit is open daily, 9 a.m. to 4 p.m.
Special event: Join horticulturist Rob Girard in the greenhouse for a Q&A on the Berkshire Botanical Garden's South African bulb collection.
When: 1-3 p.m. Saturday
Where: Berkshire Botanical Garden, corner Routes 102/183, Stockbridge, Mass.
Registration and tickets online at www.berkshirebotanical.org or by phone at 9413) 320-4794
What: Garden Club of Manchester "Think Spring" lecture by Darren Godette
When: 1 p.m., Wednesday, March 15
Where: Mettowee Mill Garden Center, Dorset, Vt.
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