Amaryllis are among the essiest houseplants to grow -- anybody can get them to bloom in a few weeks, this time of the year. For sheer brilliance and beauty, few flowers can match them.

If you have an amaryllis bulb in storage, and many gardeners probably do, now is a good time to bring it out and start it up. Or you can buy a good, fat bulb, especially one with a fat neck or a fat flower bud already peeking out. Large garden centers usually have the bulbs.

They're easy to plant and require little care: Simply decide when you want them to bloom and count back four to six weeks, which is how long it takes from planting to flowering.

Select a pot that will provide cramped quarters for the bulb. There should be no more than half an inch between the bulb and the sides of the container. You can buy packaged potting soil or make your own with equal parts of peat moss, sand or perlite, and good garden soil, thoroughly mixed.

Cover the drainage hole in the pot with stones or pieces of broken clay pot and fill the pot with the mixture to one inch of the rim to allow for watering.

Plant the bulb so that only half of it is buried in the mixture. Firm the soil and drench it with lukewarm water until the surplus drains through the drainage hole.

Put the planted bulb in a dark, warm, airy place until the first leaves or flower buds begin to show. Then move it into a light area and water thoroughly. Do not water again until the soil feels dry to the touch.

When the flowers bloom keep them out of direct sunlight and they'll last much longer.

The amaryllis must grow a number of long, spikelike leaves to help rebuild the bulb. When the flowers fade begin fertilizing to help form next year's bulb. Use a good all-purpose fertilizer, of if you prefer an organic type try fish emulsion. Fertilize the amaryllis twice a month but never fertilize dry soil because this can cause feederroot brun and retard growth.

Since the amaryllis will bloom year after year, these few tips will promote the plant's health and beauty:

When the flowers fade, return the pot to bright sunlight, or the best light that you can provide. In mid-September the outer leaves will begin to yellow, an indication that the plant needs a rest.

Cut all the leaves to within an inch of the neck of the bulb and store in a dark, cool place -- 50 degree to 55 degree F. Moisten lightly once a month.

In December or January, when the bulb begins to show signs of growth, repot to start the blooming cycle again.

You can select a variety and stagger the blooming times; red or red-and-white striped for Christmas; orange, pink or salmon to brighten the bleak months of January and February, and white for Easter.

Q -- We have two white wisteria vines that meet on a trellis overhead. They were planted years ago to shade the terrace and now they shoot six to eight feet into the air, straight up. Can we prune them ?

A -- It is the nature of a vine to grow upward, seeking light. A Chinese wisteria old enough to bloom can be pruned severely and blooms as well as if left unpruned, or even better; the Japanese blooms better if left unpruned. Both Chinese and Japanese have white varieties -- the Chinese extremely fragrant, the Japanese only slightly so. The blossoms on the Chinese open before the leaves appear, while on the Japanese they develop with the unfolding leaves.

Q -- I was given an arrangement for Christmas that included an anthurium, a beautiful flower. Can it be grown in the home ?

A -- The anthurium (flamingo flower) requires a saturated (high humidity) atmosphere that is almost impossible to maintain in the average home.

Q -- I need a book on growing plants from seeds, particularly hardwood and evergreen trees. Can you recommend one ?

A -- Seeds of Woody Plants, put together by the Forest Service of U.S. Department of Agriculture, Agriculture Handbook No. 450, published in 1974, can be purchased from Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. for $13.60.