Here’s a trick to get early spring color in your bulbs
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Four weeks ago I discussed planting spring bulbs. If you don’t get them planted before the ground freezes, there is still an easy way to get early spring color, or even color in the house — plant them in a pot. Some people prefer to have their bulbs in pots rather than in flower beds. They are easier to care for and can be moved around the yard or house during the blooming season.
There is a lot of flexibility with bulbs in pots. Species can be mixed for a longer blooming season, or they can be crowded for a more intense color show.
Most spring bulbs have a chilling requirement. This publication from the University of Delaware has a good chilling requirement chart in it. Otherwise, your bulb supplier may have chilling information for specific cultivars. Chilling requirements are met by a certain number of hours (with bulbs it is usually measured by weeks) at temperatures between 35 – 40-degrees.
Always use pots with good drainage and potting soil that drains well. Bulbs do not like to get waterlogged.
Fill the pot to a level that will put the bulbs at the depth they would be planted outside. Cover them with soil and firm them down so the soil line is about one inch below the pot rim. Water them and let the pot drain.
The planted pot should be placed in a location such as an insulated garage or unheated basement where they would get cool temperatures without freezing. If you don’t have a good location to chill potted bulbs, they can be chilled in a refrigerator before planting in a pot. The challenge with refrigerator chilling is that ethylene gas that is produced by some fruits, such as apples, is detrimental to the bulbs.
After outside potted bulbs have finished their bloom and the tops have died, they can be taken out of the pot and planted in the yard in early summer for beautiful blooms the next year. They could also be left in the pot and set to the side for next year, using the same techniques to meet the chilling requirements. It’s a good idea to pull them out to divide and totally repot every couple of years to keep the bulbs fresh and avoid disease build-up.
Another option is to plant annual flowers around them while the tops die, bringing on another splash of color just as the bulb leaves die down. These bulbs may be planted in the ground in the fall.
Bulb forcing is a technique used to get your bulbs to bloom at a time different from their natural cycle. Follow the same steps for outside potted bulbs, but bring them into the house after there has been time for the chilling requirement to be met. You should get blooms in 4 – 6 weeks.
Forced bulbs that bloom inside will probably not get enough light to regenerate the bulb and will not give satisfactory results the next year if planted outside. They can be composted.
Bulbs should be kept moist while they are blooming. Enjoy the versatility of spring bulbs and add a splash of color to your winter or spring.