Published on Thu, Sep 12, 2002 by Michelle Ensinger

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By Michelle Ensinger

I was planning on explaining how to layer bulbs for next years’ color in containers. However, as it is still too warm for planting, I thought I’d give you a quick primer on what to look for in bulbs and how to force blooms for a beautiful off season display.

Selecting healthy bulbs is an important step for good flowering and longevity.
1. Ensure the bulb is large as it will have have the largest reserve of food energy for flower/foliage. Make sure that the bulbs aren’t in holeless plastic bags.
2. They should feel solid, heavy and firm, not dried out and without cuts, mold and soft spots.
3. Sprouting bulbs have been stored in a warm area too long and chances are will continue to grow now and not in spring.

If you purchase now, keep in a cool (less than 50 F) dark location or in a refrigerator without any apples with it, as apples release ethylene gas and can cause distortion of bulbs, odd shapes, poor flower color and production. Tulip bulbs are especially susceptible to this.

When planting when cooler, remember if the bulb does not have a tip (which usually goes upwards), plant it on its side. It will give the bulb a better chance for it to send its roots and shoots in the right directions.
Bulb forcing: If you have been afraid of forcing bulbs, I want you to see how easy it is and something you may want to do throughout the cold winter months.

It is very important to choose the largest, firmest, plumpest bulbs to ensure the variety is an early bloomer, although I have found all hardy spring bulbs force well. Here is list of ones I have found that do well (using this method, I have found bulbs may only flower once as it weakens them, but sometimes if fed, the smaller bulbs may come back in the spring if fed right after flowering): botanical or species daffodils, hyacinths, crocuses, and traditional tulips, grape hyacinth, snow drops, glory-of-the-snow, squill, iris reticulata, (miniature dark blue and yellow), dutch iris, (xiphium hybrids), anemone, fressia, and paperwhites (narcissus).

The following is the mix I use and my routine. However, if you have another method that works for you, then enjoy and please share.

Soil mix – equal parts of potting soil, peat moss and perlite. To this, add one part coarse sand or fine gravel on a ratio of two parts mix to one part sand/gravel.

I usually use an odd number of one bulb to avoid a “chopped” look. Plant bulbs in a shallow container with the nose poking out. For tulips, ensure flattened side is on the outside, as the first leaf will be on the outside and the flowers will be bunched in the middle.

You can also double layer this way, by placing the bottom bulbs on a two inch layer of mix; cover to their necks, then alternatively on the next row above, carefully place more bulbs and cover. Note: press soil carefully and firmly around the bulbs.

I usually use a 10-10-10 fertilizer when watering. Ensure containers used have a drain hole, except for your water base forcing bulbs.

Ideal temperatures are 35-50 degrees over a 12–15 week period and darkness in order to grow healthy roots. Good roots = good blooms. For this length of forcing cycle it’s very important to keep bulbs moist (not wet) during this cold treatment. If cool enough, pots/bulbs can be left outside under mulch or a blanket or in a refrigerator if temperatures are too warm.
When bringing the pots inside, after their sleep, place in a bright cool location – not above 55 degrees as too much warmth too soon will rush new growth, making the stalk/flower pale and spindly. Once they bud and bloom, keeping them cooler, they will last longer, however; if this is not possible, try to keep them cooler at night to prolong their bloom time.
If you are planting your own amaryllis here are a few techniques I have found invaluable.

Use a pot slightly bigger than the bulb to avoid the pot tipping as the stalk/flower grows. I like using clay pots, as well as for forcing bulbs. In the bottom put a handful of compost or soil and then place the bulb so a third is sticking above the pot’s rim. Ensure any roots are not damaged while planting. Fill with soil to the top of the rim and firm down. Soak container in water (I usually add a diluted liquid seaweed solution to water as per instructions on container) until soil is moistened and then place in a cool (55 - 60 degrees) dark place. In about one or two weeks sprouts should appear, and then water again.

Starting bulbs in November at one or two week intervals will give you winter color throughout the holidays. After flowering, cut flower stalks back to two inches, however, leave the leaves intact. Place in a sunny, cool room until spring, and when temperatures remain above freezing.

Move the plant/pot to a shady spot outside (remember to bring inside before frost). Water and fertilize lightly until leave die back and plant becomes dormant. Store in a cool, dry place. Around Thanksgiving, repot in fresh soil, water well and enjoy the next show.

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