Bulbs May Need A Push To Produce

November 16, 2006 - Posted at 12:00 a.m.

According to well-known Texas Cooperative Extension Horticulturist Dr. Jerry Parsons, Americans buy a billion bulbs a year, mostly from Holland.

Interestingly, most bulbs are not native to Holland but originated in Europe, the Mediterranean and Middle East.

Bulbs include those referred to as corms and tubers, and there are bulbs that bloom in the summer and bulbs that bloom in the winter. Some of the most beautiful flowers are from spring-blooming bulbs, but they are not easily grown outdoors in this area, because they do not get enough chilly weather. If you want to grow bulbs in your garden that will do well and also naturalize, you must choose bulbs for the Coastal South.

If you want to grow the tulips and daffodils pictured in gardening catalogs, you may want to try forcing a few select bulbs for indoor enjoyment.


Forcing means bulbs are given an artificial winter at a time determined by you. This requires some room in a refrigerator.

Amaryllis and narcissus (paperwhites) are the easiest to grow indoors. Others are tulips, crocus, grape hyacinths and daffodils. Buy them as soon as they appear in the stores and store below 65 degrees but above freezing until you pot them up. For maximum bloom size, choose large, clean unbruised bulbs. The larger the bulb, the larger the bloom will be.

Fooling Mother Nature

Although it may not be nice to fool Mother Nature, it is necessary. The bulbs must think they have been through a long winter and that spring is approaching. Store them in your refrigerator at 40-45 degrees until the shoots reach 3-4 inches. Each bulb type will sprout at different intervals. Most will take 10 to 12 weeks, but paperwhites take only two weeks.

It is better to give them too much cold time than too little. Too little chilling time results in poor bloom quality. Don't store with fruits, because the gas produced by the fruit will impede bulb development.

Pots for Planting

Once the bulbs have chilled their prescribed time they are ready to plant. Pots should be at least twice as tall as the bulb and have good drainage. Shallow clay pots are ideal as they are heavy and "breathe."

An inch or two of gravel at the bottom will ensure good drainage and a piece of screen or broken clay pot over the bottom hole will prevent the gravel and soil from leaking through. Wash pots in a solution of one part bleach to nine parts of water.

How to Plant

Plant bulbs with the pointed end up in a commercial potting soil or soil-less mix. Cover with soil until just the shoulders are showing. Tips should be even with the top of the pot and soil should be 1/2 to 1 inch below the rim of the pot.

Allow at least 2 inches of soil below the bulb for root development. Water well and keep moist. Don't combine bulb types as each has its own cooling requirement. Fertilizer isn't necessary because the food is already stored in the bulb.

Wake-Up Time

After shoots begin to grow, place pots in a cool (60-70 degree) spot in indirect light until color appears. They will think it is wake-up time. Then, move them to a warm, well-lighted room.

Blooms last longer if kept away from direct heat sources.

Bulbs in a Hurry

Amaryllis bulbs do not require chilling. Many may come already potted; all you have to do is water. To pot your own, use a pot that is only 1 or 2 inches larger than the bulb on each side. Allow at least one-third of the bulb to sit above the soil. Water, place in a warm, sunny room and enjoy.

The amaryllis is one of the few bulbs that can be successfully planted outside after blooming. Plant a bit deeper than you had them in the pot. It may take a year or two, but once acclimated, they will bloom yearly around April.

The narcissus (paperwhite) requires only one or two weeks of chilling and will bloom in about four weeks. For a dramatic look, place several blooms in a decorative container and add spaghum moss around the top of the container.

A Tip for Tulips

Tulip bulbs have a flat side where the first leaf forms. Place the flat side toward the outside of the pot and the leaf will gracefully cover the edge of the pot. These require the longest chilling time. Tulip bulbs can be ordered pre-chilled but are more expensive.

Planting in Water

Choose vases to match the color of the bloom or clear containers so that you can watch the roots grow. Special forcing glasses are available. Water should reach just below the bulb to prevent rotting.

Bulbs forced in water will need to be thrown away because they will be too depleted to bloom again.

Planting in Pebbles

Place pebbles in the bottom of the container. Place the bulb on the pebbles and then add more pebbles to keep the bulb steady. Water should barely touch the bulb.

Paperwhites planted on rounded black stones can provide a striking design?

Coastal garden bulbs

There are a few bulbs that perform well in the coastal garden. Spring bloomers should be planted in the fall. Local nurseries usually have them available this time of the year.

Grand primo (Narcissus tazetta) and Double Roman (Narcissus tazetta orientalis) have beautiful clusters of white blooms and wonderful fragrance.

Grape hyacinth (Muscari neglectum) sports bluish-purple bell-shaped blooms and Snowflakes (Leucojum aestivum) will provide dainty wisps of white blooms.

The Oxblood lily (Rhodophiala bifida), a September bloomer, deserves mentioning because it is such a prolific performer throughout the South. Soil should be very moist at the time of planting and have good drainage.

A general rule is to plant bulbs in the garden three times as deep as the height of the bulb. After blooms fade, don't cut the foliage but let it die back naturally.

After three or four years you may want to divide the bulbs, but if you are naturalizing bulbs for a large area, they don't need to be dug up.

Be sure and look for next week's article on bulbs as gifts for the holidays.