OUR OPINION of the worth of various plants is formed largely by our own garden's site and condition; thus people with 20-foot-square gardens overhung by a ratty (or "picturesque") mulberry tree can hardly be expected to think much of roses, garden irises or poppies, but you will hear them sing the praises of hostas, violets, wild orchids and the other modest creatures that survive dank shade.

Dahlias, I have noticed, are a great continental divide, so to speak, among gardeners. I never knew anybody to like them if he had no place possible to grow them. And even if one has plenty of sun and nice soil such as corn grows in, one may not like dahlias on the general theory they are a bit like weeds or pumpkins and have no special decorative value in the garden, apart from being gloated over once they reach the size of washtubs.

Let me pay the dahlia the high tribute, then, of saying I do not grow them, have no space for them, and harbor dard suspicions against them as not being quite up to the chief garden flowers, and yet when I see them well grown I head home with absurd resolves to chop everything down and grow great beds of dahlias.

For they are very beautiful, and they bloom their best at the end of August and in September and early October. Surely any flower gets extra gold stars for blooming at the shabby end of the season?

February is an excellent month to order dahlias from firms that sell the tubers. Otherwise you can buy them at garden centers in March of April. They may be planted outdoors about the time you notice lilacs blooming along the alleys (April 20 will do) or -- even better, if you need several plants of one variety -- from cuttings.

It is simple enough to set the dahlia tubers in a shallow box of moist By no means really wet) peat moss early in April indoors. In a few days shoots will emerge, possibly six little stems from each tuber. These are cut off when three inches high and stuck in plain sand, where they root for a few days. wThey can hardly be expected to grow for very long in plain sand, but they root, and then are transferred to small pots of earth. It does nicely to plant them outdoors about May 10.

One year I grew some from cuttings and some from tubers, and (just as garden writers say) there is no difference in the two when they bloomed, though I admit it is a rare gardener who can be persuaded he will get just as good a plant from a three-inch cutting as from a great cluster of tubers.

This is also a good time to order gladiolus and other summer bulbs or roots or tubers or corms. One year I intended to plant a dozen white caladiums (the old one called "Candidum") and noted some superb bulbs at a hardware store, but by the time I got round to buying them, they were sold out; and by that time there were none to be had from the mail-order houses either. The moral is, either order them early from the catalogue houses or else buy them promptly when you see them at local stores.

The winter has been disgusting, needless to say. Never before, in the years I have fiddled about with plants, have I seen the first toothpick sprouts of crocuses as late as this year, when none appeared until Feb.3. Nor have I ever known a winter in which no daffodil shoot emerged until after Feb. 1, as this year. No harm is done, of course, but a gardener feels a bit shortchanged, not being able to roam about through January peering at his daffodil shoots.

I shall not run through a catalogue of complaints, but I do object strongly (and have so informed appropriate authorities) to some cold-damaged leaves on my plant of Osmanthus heterophyllus, the closest we can come, perhaps, to the more desirable O. fragrans or sweet olive so common along the Gulf Coast in gardens. It is not reliably hardy here. My own osmanthus, which stubbornly refuses to bloom in November as it is supposed to do (indeed, most plants of the form called "Gulftide" do not bloom, to speak of, despite what books say), once grew in a tiny Georgetown garden. Its owner dug it up rather barbarically intending to send it to the city trash dump, and it sat in that garden awaiting the trash men for some days.The Georgetown gardener was heartless enough to dig it up, but of course began to feel pangs after a few days watching it like a beached whale awaiting clean-up crew.

I was invited over, on some pretext, and almost certainly with the shrewd guess that I could not long gaze at Ozymandias (as its owner called it) without doing something. And indeed I lugged it home, not that I wanted it, and in the years since then it has grown along and bushed out and no longer looks so wretched as it did the day I first saw it. So I am some put out that this year a few of its leaves are damaged by exceptional cold.

It turns out that many gardeners are not quite sure when to plant woody creatures -- crabapples, cherries, viburnums, dogwoods, barberries, kerrias, lilacs, mock oranges and so forth. If they are to be ordered from mail-order-houses, they should be ordered now, requesting delivery the week of March 10. It may perfectly well snow the day they arrive, but no matter, they will keep perfectly well for a few days but they must not be heated up or allowed to freeze either. Keep them cool or cold.

It is important to give them a bit of coddling the first few weeks, especially not allowing them to get dry. Usually our springs suggest the worst days of Noah, and the problem is less to water the garden than to keep it from drowning in it, yet there can be such a thing as a prolonged dry spell, with a good bit of drying wind and cold, in March. Sometimes it is worthwhile to protect the still-unsprouted leaf buds of March-planted shrubs with a light wrapping of burlap. Once the thing leafs out and once the last outrageous frost of April is past, all that is needed is to see the plant does not suffer from drought, and this usually means only a little attention from the garden hose when there has been no rain for a week or so.