The Rose Garden
The Rose Garden
Roses have been so intensively interbred and developed in gardens that a quite bewildering range of types and varieties has developed. Home gardeners, though, can safely think of them under three main headings : the, the shrub and the bedding varieties.
Roses to be grown as climbers are trained against walls and screens, over pergolas and arches; the most vigorous kinds are allowed to scramble up into trees. Shrub roses can be planted on their own or in company with other shrubs. Bedding roses are most effective when planted together to make fine sheets of colour.
The bedding varieties come in various sizes of plant and flower. Some, traditionally known as hybrid tea roses, have large, notably well-shaped flowers and are the ones to choose if you value quality of bloom most highly. Others, traditionally called floribundas, carry their flowers in large clusters and do this so continuously from June to October that they are the best roses to grow when overall display is more important than individual perfection. A third sort, the miniature roses, are quite short, rarely above 30cm (1 ft), with leaves and flowers to scale. They are the ideal roses to use as edgings or to make carpets of colour; some are attractive inthough they can be a little too sophisticated to look really in keeping with conventional rock-garden species.
There are many sub-divisions of the three main groups. These include roses with single, semi-double, fully double or pompon flowers moss roses which have a curious development of moss-like glands on the calyx segments and flower stems, and roses which sprawl rather than climb and so can be used as. Also, by garden roses on to tall briar stems, it is possible to create plants like miniature trees. These are knows as ‘standards’ or, if the rose grafted on the straight stem is a climbing variety, as ‘weeping standards’ since the long flexible stems will arch over and eventually touch the ground, making a specimen like a small weeping tree.
Roses will grow in all fertile soils, alkaline, neutral or moderately acid, light, medium or heavy. The two essentials are that themust be reasonably well drained and have a readily available supply of plant food. This last is particularly important for the bedding roses which must make continuous sturdy new growth if they are to perform well. Species, most of which flower only once a year, and that only for a week or so, make less urgent demands on the soil than hybrids.
Roses thrive best in open sunny places with a free circulation of air. A few will grow in shade but they are exceptional. In very enclosed places with little air movement they can suffer badly from mildew and some varieties, especially the ramblers which are vigorous climbers bearing clusters of relatively small flowers, are also specially vulnerable to mildew when trained against walls.
Soil for roses should be well dug and manured. Anything that makes it richer will help : animal manure, decayed garden refuse, prepared town waste or sewage sludge or old mushroomfortified with a little fertilizer. The best way to buy roses is lifted from the open ground but this can only be done safely from late October until late March. At other times roses must be obtained in containers from which they can be planted without disturbing the soil around their roots.
When you’re planting roses, make the holes wide enough to accommodate all the roots — which should be spread in a natural manner — and deep enough to bring the junction between stems and rootstock to about 1 cm (1/2in) below soil level. Plants dug up from nursery beds may have some long thin roots which can be shortened a little with secateurs. Broken roots can also be trimmed neatly at the same time. Plant securely, treading the soil in firmly around the roots, but only plant when conditions are favourable, ie not when the soil is so wet that it sticks to your spade and boots nor when it is frozen.
All newly planted roses should be pruned either before they are planted, which is often most convenient but in cold places can be a bit risky, or in March, which is safe since by the time new growth appears frosts are unlikely to be sufficiently severe to do the plant any harm. Even early April is all right, provided the weather is not too warm. All strong stems of bedding roses should be cut back to 8-10cm (3-4in) and weak growths removed altogether. Vigorous shrub roses and species need not be pruned so severely and can be left with stems up to 30cm (1ft) long, and climbers can be given even more freedom, with the best stems left 60-90cm (2-3ft) long.
After the first year, pruning should be varied according to the type of rose, the way in which it is growing and the space it is required to fill. A fair general rule for all pruning is that the harder a plant is cut the stronger will be the new growth it makes. However, when a plant is in such poor condition that it has only a few hard old stems left, severe pruning will simply hasten its end. Even that may not be a bad thing, for there comes a stage when it is better to replace a weak plant than struggle to rejuvenate it.
The large-flowered bedding varieties, or hybrid teas, thrive on the hardest pruning. It can be done at any time from November until late March (but March pruning is safest in cold places, as already explained). With old bushes a few of the oldest stems, thick and with hard brown bark, may be cut out completely if they are carrying little young growth. Younger bushes will have no branches of this type but they may have some damaged or diseased stems which should be cut back to sound growth. Black or purple patches on the stems are tell-tale signs that fungi are at work and should be cut out if possible. When all this has been done the bush will probably look a good deal simpler and more open that it did at the start. It only remains to shorten the best of the remaining stems made the previous year (they are the ones with smooth green or reddish bark) by about half their length and thinner stems by two-thirds or even three-quarters. Each cut should be made just above a growth bud facing as nearly as possible outwards from the centre of the bush. This helps to direct growth outwards and so prevent a tangle of branches at the centre.
The pruning of cluster-flowered bedding roses, or floribundas, is similar in principle but different in degree. It is just as necessary to cut out old or diseased wood but there is no need to shorten good young growth as much. The best can be tipped or shortened by a third, the weakest removed or shortened by two-thirds. Most of these varieties are naturally vigorous and capable of sustaining quite a lot of growth.
True shrub roses are even more vigorous and it is the thinning operation, the removal of dead, damaged or diseased growth, that is most important. This can be followed by a little shortening and thinning, enough to preserve a well-balanced shapely bush.
Right at the end of the pruning scale come the species and climbers, many of which can be allowed to grow almost naturally with enough thinning and shortening to fit them to the areas they have to fill.
The spectacular hip of Rugosa ‘Frau Dagmar Hartopp’ — a shrub rose that is good for hedging and wild places.
Pruning needs to be supplemented by feeding for the two have a similar purpose, to maintain a constant supply of sturdy new growth. If manure or garden compost is available, rose beds and the soil around specimen bushes and climbers can be given a good dressing or mulch every year, preferably in February or March though any time is better than not at all. On its own the mulch is unlikely to be enough, and should be supplemented by a scattering of fertilizer in April with a little more to follow in June just as the bushes are coming into flower. A compound fertilizer containing about equal percentages of nitrogen, phosphoric acid and potash is best, and if the 7 :7 :7 National Growmore formula is chosen it should be applied at 100g (4oz ) per square metre in April and about half that quantity in June.
Faded flowers should be removed, and with bedding varieties this can be the opportunity for a mild summer pruning, the stems with dead flowers being cut back to a young growth or, if none can be seen, to a fat growth bud where a leaf stalk is attached to the stem.