General Cultivation for Growing Roses
ROSES in established beds only require one good annual feed of organic matter, and the time to give this is in the spring. It is both wrong and wasteful to apply it in the autumn. Wrong because it holds moisture which is already plentiful at this time of the year, and wasteful because the trees are dormant throughout the winter months and incapable of taking up nourishment. Furthermore, by the spring when they do start into growth most of the food will have been washed out of the manure.
Lime improves the condition of theand hastens the decomposition of organic matter. Without enough lime in the soil, no rose can possibly make healthy growth, and where the soil is known to be deficient, as heavy and old garden soils often are, an annual dressing in November of carbonate of lime at the rate of 4 ounces to the square yard is very beneficial. If there is any doubt about the necessity of liming, test the soil with hydrochloric acid. With soils containing sufficient calcium, an autumn dressing of basic slag at the rate of 5 ounces to the square yard is to be preferred. It is a safe and slow-acting chemical, providing both lime and phosphates; a separate application of lime is unnecessary.
For the spring feeding of organic matter, horse or farmyard manures are to be preferred, but as these are not always easy to obtain, it is often necessary to use a chemical fertilizer. The latter should not be used, however, without some organic matter to provide bulk to assist in aeration of the soil. Compost or leaf-mould are excellent substitutes, but possibly peat is the most easily obtained. It is low in manurial value itself, but it is excellent for use with the chemicals. Dress with peat afterto a depth not exceeding 2 inches, and then apply the chemicals made up as below at the rate of 4 ounces to the square yard, and very lightly fork over.
Nitrate of potash 10 parts by weight.
Superphosphate of lime 12 parts by weight.
Sulphate of lime 8 parts by weight.
Sulphate of magnesium 2 parts by weight.
Sulphate of iron 1 part by weight.
I emphasize light forking because many gardeners with more zeal than discretion fork over the rose-beds in early spring. They plunge the fork into the soil to the full depth of the tines, in and round the, and in turning over the soil break off the hair-like rootlets by which the trees take up nourishment, thus setting back the tree and doing far more harm than good. This breaking off of the rootlets is one of the reasons for subsequent poor growth. It is quite sufficient to prick over the top 2 inches of soil at the end of the year.
Except in long periods of drought, it is best not to water, but if it should prove necessary, the best way of doing it is through flower-pots sunk here and there in the beds to their full depth. The quantity needed will depend a great deal on the soil, but usually half a gallon of water to each tree once a week should be ample. With climbers on walls, where the soil is always inclined to be dry, this method of watering is by far the best. The water goes directly to where it is wanted and is not wasted by evaporation.
Much can be done to save watering by preventing evaporation, and this is accomplished by the regular use of the hoe. Drawing the hoe to and fro through the soil seals the many channels through which moisture from below is brought to the surface by capillary action.
The trees also benefit greatly from being syringed with plain water. Moisture taken up by the foliage and stems relieves the strain on the root system, in addition to aiding the foliage itself during hot, dry periods. Incidentally, in most cases of premature defoliation, plain water would do more good than the proprietary sprays so often resorted to. All syringeing should be done in the evening and not in the bright sunshine, otherwise scorching of the foliage is bound to occur.
The amount of stem to take when cutting rose blooms also often arises. With newly planted trees it is obviously harmful to cut away too much of the new growth; on the other hand, a well-grown, established tree no doubt benefits from a reasonable amount of its growth being cut away, which is equivalent to summer thinning. If in doubt, consider the size of the plant; if plenty of foliage will be left, then do not hesitate to take as long a stem as is needed.
Removing Dead Wood and Suckers
Dead wood should be cut from the tree as soon as it is noticed irrespective of the time of the year, as no purpose is served by leaving it. Other harmful growth is sucker growth, and this, too, should be removed immediately. There is often doubt as to whether or not a particular growth is a sucker. It cannot be determined by the fact that there are seven leaflets, as is sometimes thought, as many varieties throw foliage with both five and seven leaflets. The only certain way is to trace back the growth to its point of origin. If it comes from below the union of the rose and understock it is a sucker, but if above the union it is the rose and must be left. Sucker growths should be cut away in their entirety; it is not sufficient to cut them off at ground level, they should be traced right back to their source, although this may sometimes mean the removal of soil from around the roots. Sucker growths from the stems of standard roses are easily distinguished, but it is surprising how often they are left. Is it from lack of knowledge or just neglect? If from lack of knowledge, all that has to be remembered is that no growths should be permitted between the roots and the head of the plant where the stem has been budded. Any that do appear remove immediately.