by Connie Oswald Stofko
Some people can’t wait for spring; they want to see crocuses and tulips and other spring bulb plants blooming inside their homes while it’s still winter. If you’re one of those people, find out how to force bulbs with the great information here from Patti Jablonski-Dopkin, general manager at Urban Roots Cooperative Garden Market, 428 Rhode Island St., Buffalo.
Now is the time to begin the process of forcing bulbs, that is, tricking the bulbs to flower sooner than they normally would.
Of course, many gardeners enjoy having spring flowers outside in the spring, and now is the time to plant those, too. Follow the instructions in this previous article with Jablonski-Dopkin.
Urban Roots has bulbs in stock now.
Bulbs need a period of cold
The best bulbs for forcing are tulips, hyacinths, narcissus, muscari and crocus, Jablonski-Dopkin said.
The forcing process takes months to complete. The earliest you will have blooms is around the end of January. (If you want flowers for the winter holidays, you need to look for amaryllis and paperwhites that are sold during the holidays; they have already been cold treated.)
Some bulbs need a longer period than others:
- Crocus, iris reticulata, and snowdrops need 15 weeks of cold.
- Daffodils, 15 to 17 weeks.
- Tulips, 14 to 20 weeks.
- Muscari, 13 to 15 weeks.
- Scilla, 12 to 15 weeks.
- Hyacinths, 11 to 14 weeks.
Planting the bulbs
In October or November, plant the bulbs in clean pots with drainage holes. Use a soil mix with loam, peat and sand.
You could use a regular potting mix, but you want a bit of grit in the mix so you have good drainage, Jablonski-Dopkin said. If the mix has too much peat, you may be looking at rotting issues.
Do not add fertilizer to the soil, she said. Bulbs have everything they need in them. If you add fertilizer, you’ll just get leaf growth and no flowers.
In a six-inch pot, you can plant this many bulbs:
- 15 crocus bulbs or
- 6 tulip or
- 4-6 narcissus or
- 3 hyacinths.
Note: The pot size is the diameter of the opening of the pot.
Plant the bulbs so that the tips are above the soil line. When you plant them outside in the ground, you plant them more deeply, but when forcing them, they’re planted less deeply to avoid rotting, she explained.
Storing bulbs during the cold period
Store the bulbs in the pots in an unheated basement, attic, unheated garage or outside in a cold frame. The optimal air temperature should be 35 – 48 degrees Fahrenheit.
You could place the pots in your refrigerator only if you don’t store fruits and vegetables in there. Apples and many other fruits and vegetables give off ethylene gas, which will kill the bulbs, she noted. A dorm fridge or beer fridge with no fruits or vegetables would work.
Transition slowly to warmer temperatures
After the necessary number of weeks for the bulb you have planted, short shoots should emerge.
Bring the pot into a bright area that is still cool, about 55 to 60 degrees. Don’t bring them immediately into your warm living room
“You don’t want to shock them,” Jablonski-Dopkin said. “You need a bit of a transition.”
In three to four weeks you will have blooms.
After you have enjoyed the flowers inside during the winter, can you plant the bulb outside in spring?
“You can,” she said. “I feel there’s about a fifty-fifty chance they will flower again. Plant them as soon as you can work the soil. Add some bonemeal to the soil to help the bulb rejuvenate. I think it’s worth a shot.”