HORTICULTURAL NOTES.

Otago Witness, Issue 3116, 3 December 1913, Page 12

HORTICULTURAL NOTES.

By J. Gebbie.

THINNING ROSE GROWTHS. Many of the rambler rosee, especially those of the wichuraiana type, send up quite a mass of growth from the base ot the plant at this season. To give the plants every encouragement to make strong and vigorous shoots, some* of the giowths should be thinned out, especially those that are weak, which, if allowed to remain, would never develop into good shoots that would flower satisfactorily, but to a certain extent would hinder the growth ol the belter ones. In the case of dwarf or bush roses, it sometimes happens that a piece of last year s wood left at the pruning-timo produces a number of weak growths from top to bottom. koine oi these small growths should be cut off so as to strengthen some of the others, otherwise there will be no good wood made at all this season. The bush will become full of weak spindly shoots that are quite useless. By thinning out the weak ones now, and especially those which point towards the centre of the bush, much disappointment will bo prevented. VIOLAS. Violas and pansies are now blooming freely, and in order to have them m bloom as lon°* us possible all faded flowers shoual bo picked off so as to prevent their forming seed. The plants will still make a good deal of growth, if well watered in dry weather, but if seed pods are allowed to form their growth will bo checked considerably. When the plants become old and straggling, these straggling growths may be cut off and a little lino mould sifted over the centre of tin? plants. Young growths will soon push forth, and the plains will bloom again with renewed vigour. V A KIEG A TED P L A N I'S. As a rule, variegated plants are less robust than the green leaved ones. Wo have only to examine the hollies, some of our stove and greenhouse plants, and come of our border plants, to sec and fully realise the fact that the silver and gold-leaved varieties are less robust than those that are quite gi'Cvii. The variegated or light portion of the leaf is caused by the absence of chlorophyll. Chlorophyll is the green colouring substance formed by very small "■rains, lying loosely in the cells of tno Tissue of "the leaf and stems of the plants. The white or golden edges of leaves arc maintained in good health simply because of the chlorophyll contained in the green portion of the leaf, but all such leaves are rarely its large and robust as the green ones’on the same kind of plant. If the whole plant became by some means quite white, it would soon die. When we sec sickly-looking plants, the leaves of which should in a 'healthy condition bo of a dense green, wo at once know that the plant is unhealthy and lacks chlorophyll. NITROGENOUS MANURES. The effect of nitrogenous manures in the soil is to stimulate the growth of loaf, stem, and shoots, and such manures must be used with caution, and their successful use decn ~l~d jndrmcr.t end the cimultaneous supply of plioephates and potash. Nitrate of soda is obtained in enormous quantities from Chile, and is now' recognised as a necessary adjunct to economical farming. Nitrate "absorbs moisture very readily, and should be stored in a dry place, otherwise it may soon be destroyed by rain or damp. Nitrate is not retained by soil, being constantly washed out by rain, eo that” applications of nitrate must not be

excessive, or else the rain will wash it beyond the reach of the roots. A little and often is the beet system for applying nitrate where it is needed in large quantities. Such plants as cabbages, asparagus, celery, rhubarb, and sea kale can bo liberally dressed with nitrate in successive email doses, only to be applied when a crop is in active growth. Nitrate of potash, or saltpetre, is invaluable for use in the greenhouse, in the form of a liquid manure, for stimulating tomatoes, vines, and not plants. An ideal liquid manure suitable for all plants as a general stimulant can bo obtained by dissolving half an ounce each of saltpetre and phosphate of potash in a gallon of water. Sulphate of ammonia is obtained from gasworks and iron and shale works as a waste product, <ind its output has greatly increased of late years. For the garden, sulphate of ammonia has special properties that make it more desirable than nitrate for general use. HOLLYHOCK RUST. The hollyhock rust disfigures the foliage of the plants to such an extent as to mar the beauty of the whole plant, and prevents their more general cultivation. Some florists assert there is no cure; this may be so in the case of over-propagated named varieties—-that is, varieties propagated from cuttings and buds year after year, —and sue!i plants are weaker and not so well able to stand the ravages of disease as those raised from seeds. Seedling hollyhocks raised from a good strain can he enabled to battle successfully with the disease provided it be systematically sprayed with Bordeaux mixture. On applying Bordeaux to an infected plant, disease spots are destroyed and drop out of the older leaves, leaving small holes, while the still healthy younger loaves aye enabled to withstand a further extension of the fungus. An application of the Bordeaux to the crowns in early spring, followed by two or three applications at intervals to the expanding foliage during the season, will generally produce a clean and healthy plant. THE LAWN. There is no time like the early .autumn for top-dressing any lawn that requires a dressing. The soil is then warm, and there is growth in the grass. Work up any bare patches, add some fresh soil, and fill the bare parte with fresh turf if available. When all the patching is finished, cover the whole lawn with the nicest soil procurable, giving at the same time a good sprinkling of fertiliser. In top-dressing be sure that the soil used is free from the seeds cif woods. Never be in too great a hurry to roll a new lawn. Get the grass to grow and cover before rolling. Give the i-oots a chance to run through the soil, and they will not be long in making the surface green. Remember that root first and growth afterwards is the order. You cannot have a good lawn unless you give it attention in the way of manure, topdressing, weeding, rolling, and cutting. Good lawns are not made in a day.

DOUBLE FLOWERING DEUTZIAS. These are both ornamental and distinct flowering shrubs. A good specimen of it is not often met with, yet when covered with a profusion of good blossoms it is reallv a very beautiful shrub. It is not particular as to soil and situation, but succeeds best in a fairly deep, open loam, that is not dried up during summer. Those deutzilas are much improved by cutting out old and exhausted wood, allowing the younger shoots to develop, which treatment results in finer blossoms. Dcutzia erenata flore pleno and Pride of Rochester are two well-marked forms, and both arc beautiful. This last-named produces pure

white flowers, and those of the first have the outside of the petals deeply tinged with rosy purple. This feature is especially noticeable in the bud state, but is also prominent in all stages of the flower.