No good deed ever goes unpunished, as Alice Roosevelt used to say, and I should ask gardeners please not to try to get irises anymore from Olin and Mary Barnes, whose delightful assortment of hard-to-find varieties I mentioned several weeks ago. We both thought maybe 10 or 20 people would be interested in these irises, but the Barneses have received more than 2,500 letters by July 1, and this is far more than they can cope with.

The trouble with the mass media is, of course, the great number of people who (according to sunspots, I believe, since it is utterly unpredictable what will catch their eye) may suddenly respond to something. And one of the main problems of this column is that I jabber along as I would to a friend, not knowing any other way, and sometimes forget the number of people who read the column, not because it's mine (if a gorilla did it, maybe even more readers would be attracted) but because it appears in this newspaper. So my apologies to those who have been inconvenienced, especially including the poor Barneses.

But I think the response indicates that many gardeners would be happy to find a greater and wider assortment of plants than can be found at garden centers. All over America and England there are small nurseries with wonderful things out of the ordinary. The trouble is the gardener is not usually aware of them, and such growers are often hobbyists rather than large commercial firms, and cannot afford to advertise, and if they do advertise they are swamped with customers, most of whom will be disappointed.

Still, I am not convinced it is a crime to mention them occasionally. After all, people read about things being auctioned off, knowing there is only one example for sale, and knowing they cannot possibly afford it. But they still like knowing about it. With small nurseries the damage is that the reader reasonably expects he can buy (unlike an old table that is going to sell for a million dollars) and is rightly disappointed. It speaks well for the American public that few have written me in fury, but I will try to be more careful from now on.

Still, it is equally infuriating to read about some plant without any idea where to get it.

I returned five days ago from London, a base from which to visit some fine gardens in Wales and England, sponsored by Horticulture magazine and arranged with the help of the Royal Horticultural Society.

The grandest garden was possibly Hidcote, at Chipping Campden, which was full of roses that Americans go to pieces over (though they rarely plant them) and such wonderful blue poppies from China and Tibet as Meconopsis grandis and its relatives. They are by no means easy in England, and apparently almost impossible here with our hot summer nights, so it was a luxury to see them. The famous red border of this garden includes such plebeian creatures as the double tawny daylily called 'Kwanso,' which is orange and not red at all, and such relatively ancient dahlias as 'Bishop of Llandaff,' which most American gardeners discarded years ago. But they also have gorgeous red or bronze-leaved coral bells (Heucheras) and rodgersias with copper-bronze foliage, along with purple or copper foliage from Rosa glauca (or R. rubrifolia as we used to call it) and various purple forms of the smoke bush (Cotinus).

This border is a nearly perfect example of the hard truth that the effect of a garden depends very little on rarities, and almost entirely on color, texture, felicitous grouping of the various plants, and (here is the the cruelest factor) the framework of the garden itself. At Hidcote, in this very border, a good bit depends on magnificent masonry piers and wrought gates that nowadays would cost two fortunes and a half, and on pleached hornbeams and brick walls and a vista toward Bredon Hill, etc., etc.

The truth is that those of us with little cat-run narrow gardens in large cities need not even dream of such effects as those of Hidcote, but curiously enough one of the things we might learn from such a garden (which seems at first so limitless, so jammed with flowers) is restraint. Instead of the repeated huge clumps of the common daylily, we would certainly use 20 varieties of the best modern red varieties, and instead of a broad sweep of some plant we would yield to the temptation of using many more kinds of plants. We would wind up with what most of us have -- a decidedly spotty effect in which perhaps every plant is greatly loved but which is not nearly so satisfying for visitors to see as the red border of Hidcote.

Again, in the great herbaceous borders of Wisley Gardens at London I stepped off the dimensions of some of the clumps that are so satisfying to see as one enters these borders. One clump of ordinary catmint (Nepeta) which made a decided spot of blue was 18 feet long. Which of us is going to give 18 feet to catmint? We'll have one fat plant, then some blue lobelia, then a blue sage, then a Russian sage, then a balloon flower, and we'll wonder why the patch of blue does not count, as it does at Wisley.

If the creek don't rise I shall say some more about the lessons to be learned (or at least observed) from the grand British gardens, but I should end on a note of comfort (for we all like to know that great gardens have disasters much like our own) starting with the vast number of roses that balled this year, the buds getting all stuck with rain and turning brown and rotting without opening. Such glorious varieties as 'Blairi No. 2,' 'Mme. Caroline Testout,' 'Mme. Isaac Pereire,' and indeed almost all roses that are extremely double suffered badly in June and early July. Worse than those varieties suffer here even in the wettest years.

Arriving home at Dulles Airport, I was struck anew with the incomparable beauty of our wild black locust, which to my mind is the most beautiful of all American trees for a garden. In Britain it is rarely planted in gardens in its common form; they prefer its gold-leaf variety, 'Frisia,' which I got out of my system 10 years ago. Exciting, but not as beautiful as the plain wild green form. They also go to pieces for any of the locusts with pink flowers, though they do not seem to grow 'Monument,' which I like better than the other pinks. Like us, the English grow what they are offered, and like us they assume that what they grow is the best there is. Not always true.

And what a joy to feel our admirable sun and to hear our agreeable bugs that chirp, buzz and cheep at dawn and dusk, and our elegant lightning bugs -- none of these known to Britain. And to see my several kinds of blue water lilies in bloom, none of which will endure the English climate even in favored places, and my big angel trumpets that will not do in England because it is too sunless and cold there for them.

It is so much easier to garden here than in England that again I felt ashamed my garden is such a poor thing to see. The secret of their gardens is labor, knowledge, money, and the shortcoming of our own gardens (I speak of those like mine) is simply laziness, and an evil tendency to avoid work except when the weather is perfect.