Year in, year out, one excellent family of easy, varied plants gives gardeners all over the world what they want – and yet we never dwell on them.

Are we so ungrateful because the family of shrubby potentillas has been taken up by landscape architects and used so often in public spaces above chopped bark in dull company? Who remembers that even the most obvious yellow-flowered varieties are all classified botanically as members of the rose family? They are not to blame for their dependability and, in fact, only a few varieties turn up in “trouble-free” plantings. There are dozens of others and they give me such pleasure. They flower for months and almost never die out. They have to be a top choice for anyone beginning a flower garden and they are remarkably strong even in harsh, hot gardens outside Britain.

I will be busy with mine this weekend because it is a good time to take cuttings off them and root them for two or three years down the line. Take the laterally lying side growths, which are usually the younger shoots, and cut lengths of about 4ins at a time. Strip off the lower leaves and remove the inevitable flower buds. Put the stems that remain into well-watered rooting compost in pots about 4ins wide and cover the pots over with a plastic bag or a plastic water bottle with the bottom cut off. The cuttings will sweat away under this cover and by late September a fair proportion will have rooted. They can then be potted on individually and after a year will be catching up with the instantly mature plants that cost more than £8 each in garden centres.

From time to time I go on potentilla buying sprees. The last one was three years ago when I had no particular spaces for more and yet a new half-dozen found homes in awkward places. Every one of them is still flowering after a fine summer’s performance. They keep up the show, from early June into September, more readily than any other shrub and, as they are mostly under 3ft high and wide, they can fit into neglected spaces beside steps or on banks or at the front of mixed borders. They look best as individuals and it is prettier to repeat them down a border rather than to mass several into one heavy group. I like their individual shapes.

What holds gardeners back? Familiarity is one culprit and knowing gardeners think that winter behaviour is another. The shrubby forms of potentilla look brown and dead from November onwards and if you break their stems they will usually look brown inside too, a conventional sign of death. Actually potentillas are alive nonetheless and are the least likely victims of frost.

I would not want a long hedge of them in my main sightline, looking outwards from indoors in winter. I prefer to alternate the potentillas in such low, loose hedges with the hardiest of all white-flowered cistuses, Cistus laurifolius. The two plants go well together, although this evergreen cistus will be the taller and bigger. Do not cram the plants too closely even if they look equally small and vulnerable when first bought. The potentillas, but not this cistus, can be pruned as you wish in spring, though not into hardened older wood. The previous season’s stems can be shortened by half to contain their shape and encourage even more flowers.

Potentilla Pink Princess

Which are the winners? Varieties whose flowers tend to red-orange caused a stir when they first appeared as chance colours but I rate the paler flowers above them. Potentillas have been well ranked by the Royal Horticultural Society and varieties with the letters AGM after their names deserve their Award of Garden Merit. I have to put the well-branched Primrose Beauty in the top rank as it also has such pretty soft silvery leaves. Tilford Cream is taller and wider with bigger flowers in a very pretty cream-yellow. The best spreader, at a height of about 3ft, is the admirable Abbotswood, with white flowers and an amazingly long season. Space a few round the garden and you will never have a dull moment from May to late September. What else flowers for so long without any dead-heading, even on dry soil? Abbotswood turned up in a great Gloucestershire garden and has given such pleasure ever since. Remember that it is a shrub and that it, too, is better as a specimen, not as an item for a great big group as designers sometimes deploy it.

Pink-flowered Princess is another star, though the flowers become smaller as the season goes on. Like other pinks, this Princess shows even better colour in slight shade. The RHS Plantfinder lists nearly 80 different varieties of the basic shrubby Potentilla fruticosa and I can add at least two, including the excellent Wessex Silver, which I picked up on a garden visit and which seems to flower constantly in a fine shade of pale yellow. Numbers have multiplied since the days when the large-flowered yellow Elizabeth was a newish sensation. She is still excellent but so well known that I would hesitate to make her a mainstay nowadays. At a much lower level I am glad to see that the good bright yellow Wickwar Trailer is still in the trade. It is excellent above a low wall and my plant, at its best this weekend, goes back to its original selector, the fine nurseryman George Osmond, a man for whom plants grew in happy sympathy.

Once only I ended by killing dozens of potentillas. I had envisaged their herbaceous relations, Potentilla Gibsons Scarlet, running in strong red flower as a contrast to my five avenues of clipped flowering pears and hornbeams. I propagated the scarlets and planted them in anticipation in the gaps between the avenues’ lines. Most of them grew but so did the avenues and when the potentillas flowered they were already interestingly short of light and reverted to a strange sort of blotched pink-yellow. By the next year the avenues were too high and the tree-roots were seeing off anything at ground level. All the scarlets have now gone, as has much of the light. I look and wonder what possessed me except impatience, but they fell victim to a grander cause. It takes a lot to kill a potentilla but a 20ft high avenue eventually does the trick.