IT'S MY own fault, of course, for being extremely fond of water lilies; so that now it strikes me an inordinate number of people ask me about them.

It ought to be said somewhere that no water lily is more beautiful than our native wild Nymphaea odorata, the scented white water lily found in ponds over most of the eastern United States. It is recognized by its circular (not horseshoe-shaped) leaves of fresh pea green.

It should always be grown in a tub, not in earth in the bottom of a pond, since it spreads with optimistic vigor and soon becomes an embarrassment in a natural pond. But when confined to a tub holding a cubic foot of earth or so, it behaves rather well.

Honesty compels me to say that no water lily I have ever grown behaves all that well. Even the least vigorous sorts, once they settle in for two or three years, start peering over the side of their tub and sending down roots into the mud or mulm at the bottom of the pool.

The gardener is commonly surprised when he lifts the tub, or tries to, to discover that half the plant is over the side and rooted firmly on the mud bottom.

The very worst, in this respect, is the common pink lotus from India, Nelumbium rosea. It is sometimes said, possibly by people in harsh climates or by people who do not know what they are talking about, that if a lotus is given a circular tub its tuberous roots can go round and round contentedly for two or three years. Ha.

The minute the lotus starts to grow well it creeps over the side of the tub and sends fleshy stems to the bottom. It can cover a circular pool 10 feet in diameter solid with its tuberous roots in its second year, while the innocent (and highly unobservant) gardener still supposes it is sitting in its tub, only perhaps leaning out a bit. I have harvested several hundred of these jointed roots from one lotus after the second summer.

No plant in the world is more beautiful in leaf and flower. But a sharp watch should be kept to insure the lotus stays within bounds.

I was rather pleased, and not much surprised, to notice at the Kenilworth Aquatic Gardens that the pink lotus there had traveled beneath a dirt road 10 feet wide into a pond on the other side.

In the South, the native yellow lotus grows so densely at the edge of lakes that it's hard to get a rowboat to shore, and many a pond built for cattle has become solid with this lotus.

All of which is splendid. But the gardner should not suppose he can simply plant a lotus tuber and forget it, and that it will still make a lovely clump three years later. No. It will have covered the entire pool.

Against a wall facing north I have a small horse trough of galvanized steel four feet long and 28 or 30 inches wide and two feet deep. It additionally shaded (not only by the wall) on the east by a hydrangea I am fond of -- with leaves blotched white -- and on the west by a grape, "Monticello" which get so little sun I fear it will never fruit.

I do not expect miracles. And water lilies, of all plants adore the full sun without any shade at all at any time of the day. But of course they make do with less than perfect conditions.Do not we all.

But my problem in this small tank was to grow something green in it. I could hardly expect a water lily to flourish or even endure in so sunless a spot. And the trough is too small for a nuphar, or spatterdock: that admirable genus of a dozen or so species that grows in running (as well as stagnant) water, and which endures colder temperatures in the water than any of our garden water lilies. It has, moreover, beautiful leaves that rise a few inches out of the water. The blooms are like little doorknobs, clear rich yellow, but no larger than a quarter or, at best, a silver dollar. Compared to the showy water lilies of gardens, they are pretty plain, but their foliage is even waxier and more leathery than that of regular water lilies, so the nuphar does have its uses.

But is likes to grow very large, making great rafts of leaves cold rivers of the Ozarks, for instance, and my shady horse trough is much too small for it to show its beauty, so I ruled out the nuphar.

I did pop in a tub of the yellow water lily, "Chromatella," an old Marliac variety that came out about 1888. It is exquisite in its beauty and I really prefer it to some other yellows I have grown that are theoretically showier. It is well know that "Chromatella" endures more shade than most other hardy water lilies, but even so it should have about four hours of direct sun each day if it is to flower.

Imagine my pleasure to see "Chromatella" flowering in the almost sunless horse trough. Not as large, not as richly colored as it should be, but living and blooming half-heartedly with hardly any sun at all.

If I had endless space I'd grow every water lily in cultivation -- there are several hundred kinds -- and I think they must all be beautiful; certainly; all the ones I know about are handsome. And I shall not weary you with discussing varieties again. But one thing I see new gardeners err in with water lilies, when they are planting them in their pools. Sometimes they think they will do the water lilies a favor and give them really splendid soil to grow in, with plenty of leaf mould, a bit of peat moss, plenty of rotted manure and so on.

This is a mistake. Manure, while splendid if it is cow manure and very well rotted, can add so much organic life to the pool that for two year (and maybe forever, for all I know) the water will have a distinctly green cast.

Galdfish think it is glorious, and they grow with astounding speed in such rich green water (assuming each little goldfish has five square feet or so of water surface -- otherwise they will not only not grow fast but will speedily die, since the minute organisms that turn the water green also use up a lot of oxygen ordinarily available in the water for the fish).

But the gardener does not have that sparkling black crystal look, with a golden cast, that he likes to see in his garden pool.

In choosing earth for the tubs in which water lilies grow, therefore, I would avoid all natural manures. Once the water lily is established in a few months, and when it seems to be slowing down a bit in its growth, a handful of 5-10-5 chemical fertilizer may be rammed down into the mud of the tub, without taking it up out of the water. You want to be excessively careful, however, not to use any of those fertilizers that have weed killers in them, because they will kill the water lily with great promptness.

Actually in the garden pool the great problem is keeping the water lilies from covering the entire surface, not to make them grow. You want, after all, open space to reflect the sky, not a solid mat of green water lily leaves.

Ordinary garden dirt does quite well. I have read that water lily roots do not readily penetrate clay, but that is not my experience. I have always found that the more tenacious and sticky the soil is, the better the water lilies like it. They do not care for woods soil or leaf mould. They abhor peat. They should not be given sand (which has no nourishment in it, and in a mere cubic foot of soil you do not want to short-change the water lily by giving it sand).

Dirt that seems to you right for growing good roses, peonies, oaks, will do nicely. If you know anybody with a pasture and good cattle on it, possibly you can wangle dirt from there, lifting the grass and digging you dirt from the first foot beneath the grass.

Water lilies will grow, I suppose, in almost any soil. But avoid a lot of organic stuff that will foul the water. And try to give each water lily plant a good cubic foot of earth to grow in. That is more, by the way, than the gardener thinks it is. Some gardeners are not very cubic minded, of course, and say to themselves, "Oh, I imagine this bucket is about a cubic foot," when it is not. Gardeners who do not think in cubic feet should think in bushels. Give each water lily a bushel of earth.

And always full sun. Unless, of course, the pool is partly shaded, in which case do as well as you can and hope for the best. And be grateful. But do not expect even so vigorous and amiable a plant as "Chromatella" to flower very freely without full sun.