Leave fake Christmas decorations to the windows of hardware and dime stores. In your own home, the genuine beauty of real wreaths, trees, centerpieces and pine roping far surpasses the mild inconveniences of falling needles. Besides, there are ways of delaying the needle fall.

First of all, be aware, if you have small children or stupid pets, that all broadleaf evergreens are poisonous to mammals. These include holly, laurel, boxwood and yew; in other words, the non-needle types. Berries found on these plants can also be poisonous, as well as berries on certain piney evergreens. Mistletoe is also poisonous. These plants are unlikely to kill cat, dog or baby, but it could make them quite sick. Just to be on the safe side, if you're going to decorate with any broadleaf evergreens, keep them high or inaccessible to curious creatures.

Contrary to much popular belief, poinsettias are not poisonous, even though they are milky-sapped plants, which often are poisonous. A friend of mine proved this to herself once by eating part of a poinsettia, which may sound a little weird, but it was effective. She didn't get sick. I wouldn't advise doing this sort of thing lightly, however.

Your basic needle-type greens -- all pines, cedars, spruces -- are quite safe, except for the occasional berry. Keep in mind, also, that small pine cones, while not inherently poisonous, can be a hazard to children if swallowed hole. They can get stuck in a child's throat.

This weekend is the big rush to get out Christmas trees and live materials for wreath-making or general decoration. You'll probably be putting up your decorations before you put up the tree. When you get your greens home from the flower or garden center, to delay needle-drop, soak them at least overnight in cold water. Do this in the tub or laundry sink. If all you have is a regular kitchen sink, put them in after you've done the dishes. Next morning, or whenever you're ready to start working, drain the water from the tub, lift the greens and shake them roughly to get rid of excess water. At that point you can leave them alone a few hours to dry in the tub or sink. Then they'll be ready to put up. WREATH-MAKING: The best and easiest wreaths I've made began with a straw base. You can get these at any garden center, wrapped in green plastic. When you get your wreath base, pick up a package of florist's hooks, which look a lot like dangerous hair pins (keep these away from kids too) and make the job even easier. You can either remove the plastic from the wreath base or just punch several holes in it, and soak it, too, overnight. The advantage of leaving the plastic on is that when wet, the base will not be as messy to work with. Jam pre-soaked stalks of pines or boxwood, holly and spruce into the pliable straw, using the florist's hooks to fasten the greens tightly. Fill in holes with smaller stems, add a bow, or a few tiny Christmas balls, or a favorite ornament, and you've got yourself a handsome home-made wreath. You really don't have to do anything more to prolong the wreath's freshness, but some people are moved to soak the whole thing again in a couple of weeks to keep it fresher well past the holidays. CHRISTMAS TREES: Treat your cut tree like a long- stemmed rose. When you're ready to put it up, make a fresh, slightly diagonal cut on the trunk to expose new cells that will draw up water and delay needle-drop. Anchor the tree in a bucket or one of those special holders that will also hold water. Don't cover up the base, because you're going to have to monitor water supply to the tree if you want to keep it from drying out. If you're a good citizen, you've already dug a hole for a live tree that you're going to transplant after the holidays. If not, then get out there and dig one right away, removing the soil to a plastic bag, which will keep it warm and moist, and fill the hole with leaves. When you buy your balled tree, keep it in the garage or on a porch, where it will be protected from the wind, until Christmas Eve. Then bring it into the house then and put it in a bucket, where you will soak the root ball with lukewarm water, not allowing too much to accumulate in the bottom of the bucket (remember, this is now a houseplant, until you put it outside). Try to get the tree outside and into its permanent growing place within two weeks. Most people recommend 10 days, but I've gone as long as two and a half weeks of leaving it indoors before planting, and it's done fine. Pines, balsams and spruces are very hardy for this type of arrangement. Personally, I have always wanted a Hoop's blue spruce -- one of those luscious, blue-gray masterpieces -- as a Christmas tree that I then can plant outside. Unfortunately, these trees are so expensive (about $200 to $300 each) that it would be foolish to risk planting such a gem during the coldest time of the year. POINSETTIAS: I have few words of wisdom on the subject of care and maintenance of poinsettias, never having had much luck with them myself. However, I did splurge and get a lovely hanging basket this year, and it seems to be doing remarkably well, considering my ability to kill house plants. I mist it as often as I remember, and have kept the soil fairly moist, which is an accomplishment in itself in a room that is heated with the driest kind of heat -- a wood stove. The key to maintaining healthy poinsettias is humidity. Another method, if you don't own a mister, is to place the plant on a tray of marbles or pebbles, and keep a constant supply of water in the tray. The evaporating water will keep the plant from drying out.