If you have some leftover bulbs that didn’t make it into the ground before it started snowing, then “forcing” them to bloom is a way to bring spring cheer into the house. Emma Erler, host of Homegrown NH and lead horticulturist with Kirkwood Gardens, says you can do this with tulips, daffodils, hyacinth, crocus, and muscari.
However, you need to have planned ahead! Hardy bulbs like daffodils, tulips, and hyacinths require an extended period (12-15 weeks) of cold temperatures between 35-50F to initiate shoots and flowers.
Any cool, dark storage space that stays within this temperature range will do, such as a basement, root cellar, cold frame, or refrigerator.
If your bulbs have been chilling over the winter, here’s what you need to know to force them to bloom, according to Erler.
Bulbs require good drainage; all pots must have one hole in the bottom. It must be deep enough for growing roots – at least 8” deep for larger bulbs.
Use a quality soilless potting mix from the garden center. These drain quickly but hold moisture and provide stability.
Fill with an inch or two of potting mix and arrange bulbs so the tops sit below the container rim. Cover with more potting mix and leave room at the rim for watering.
Move the pot to a warm, bright spot, like a sunny window sill. Once plants start flowering, relocate them out of direct sun in order to prolong the flowering period.
After the bulbs bloom, they can be planted in your garden, but it may take them a few years to recover.
Pre-chilled bulbs from the garden center, such as hyacinths or tender narcissus like paperwhites are even easier, just plant and place them on a warm windowsill!
They can be placed in a container of pebbles and water, with the bulb bases touching the water.
See you in the garden!
Homegrown New Hampshire is a collaboration between Squam Lakes Natural Science Center and NHPR.
