Bulb Forcing 101: How to Get Spring Blooms in the Dead of Winter
By Kathy Jentz
Didn't get all your bulbs planted before the ground froze? Don't discard them! Instead pot them up for indoor forcing and enjoy an early springtime in the depths of winter.
If you were a good little gardener and got all your bulbs in the ground on time, there are still a few bulbs hanging around unsold at local area garden centers and on major markdown sales on the web and through mail order, snap them up now at these bargain basement prices and consider yourself a savvy customer. Next year, when you place your bulb orders, add a few extra to your quantities to set aside specifically for forcing.
Never forced bulbs before? Nothing to it. Here are the basics and a few extra tips I've learned from past experiments:
1. Bulb Selection. You don't need to buy any specific variety or kinds. You can just select a few bulbs from those that you would buy for outside plantings. After they are done livening up your winter home, you can plant them outside after the last frost so that they will return annually with your other bulbs. One note of caution, indoor bulbs can sometimes give off potent smells. Some people love them, some don't -- paperwhites and hyacinth are especially notoriously in the love/hate category. Experiment a bit, and you'll soon learn which scents are to your tastes and which are just too overpowering for inside your home.
2. Timing. Keep in mind that bulbs bloom within three-four weeks of removal from cold storage, which lasts about 12-16 weeks. So if you want blooms for a specific occasion, you need to work about 16-20 weeks in advance for planting time.
3. Bulb Planting. Regular bulbs should be planted in soil, but at a shallower depth than you would outside. The top of the bulb should be even with the soil line and have about 2" of soil below for root development. The container should have drainage holes. Because it will be inside your house and no one likes a leaky mess on their furniture, I recommended lining the bottom of the pot with scrap landscape fabric and placing the pot on a good-sized saucer filled with a layer pebbles. Place the bulbs pointy side up and with the "flat" side towards the outside of the pot and as tight together as you like. Crowding them actually makes a nicer visual effect than spacing them far apart. Tight quarters also helps the foliage from growing out too much and flopping over. Water the newly planted bulbs well. Place the pots in plastic newspaper sleeves to maintain a moist environment.
4. Cold Storage/Removal for Flowering. Place the potted-up bulbs in cold storage for about 12 weeks. Cold storage should be roughly 40-50 degrees and without light. Storage areas might include your basement, garage, or the crisper drawer in your refrigerator. Different bulbs have different cold cycle times but most are between 12-16 weeks. (Tulips need the most time at a full 16 weeks.) Mark your calendars so that you don't forget about them. When you first remove them from storage, place them in indirect light and away from a heat source to prevent "legginess." After two weeks, when they have sprouted and are several inches high, move them to a sunny, warm window. Once a flowerhead or bud starts to develop, you can then move it to your desired location with indirect sunlight to prolong the bloom life. Keep them watered regularly as soon as you remove them from cold storage. Enjoy!
