No modem Rose garden is complete without its Penzance Briers. Beautiful in blossom, attractive later in the season owing to their brightly coloured heps, graceful in growth, sweetleaved, the lovely race of garden Roses evolved by Lord Penzance from the common Sweet Brier, Rosa rubiginosa, is one that must grow in favour as the years roll on.
The common advice to avoid pruning Penzance Briers is based on a sound principle. Assuredly these lovely Roses must not be pruned as dwarf and standard Roses for exhibition are pruned - that is, cut to within a few eyes of the soil. Such procedure could have but one result - the production of gross, unripe, flowerless wood.
Nevertheless, it can hardly be maintained that it is advisable to leave plants absolutely untouched with the knife year after year. Such a line of action - or rather inaction - would result in a thicket of growth, much of which, being weak and immature on the one hand or old and worn out on the other, would produce few and poor flowers.
To secure pyramids of bloom - tall columns clothed from top to bottom with flowers - a modified long-rod system of pruning is the best. Any reader who has a bed of Penzance Briers in full bloom in his garden (and I, as I write, am in that happy position) will observe that flowers are borne not only on side shoots from the main canes, but on short basal growths. At the same time he will notice strong young shoots springing up from the rootstock, and others from the lower part of the older canes.
Now, to leave the plants unpruned altogether would be to get a tangle of growths, some old and exhausted from flowering, others weak from overcrowding. By a judicious removal of old flowered wood, and training up of new canes to become plump and well ripened by exposure to sun and air, this tangle is avoided, and a succession of vigorous, healthy, floriferous wood is maintained.
The knife may further be advantageously used to shorten strong flowering canes which are not fully ripened their entire length. Such canes need not be cut hard, but the soft upper portion may be removed.
As regards the side branches which have flowered and subsequently borne clusters of heps, they may be shortened to a couple of buds.