HORTICULTURE.

Taranaki Daily News, 23 September 1922, Page 6

HORTICULTURE.

ADVICE TO GARDENERS. ADDRESS BY MR. W. H. TAYLOR. About thirty amateur gardeners met at New Plymouth on Tuesday to hear the Government horticulturist, Mr. W. H. Taylor, deliver an address of great interest and instruction to all who own, or contemplated owning, a productive vegetable garden. Mr. W. B. Grant presided, and there were also present Mr. J. A. Campbell, director of the Horticulture Division, and Mr. A. K. Cockayne, Biologist for the Department of Agriculture. Mr. Taylor’s talk took the lines of a discourse upon fertilising soils, mainly for Vegetable growing. Essential conditions for the establishment of a first class garden were that the soil should be loose for a certain distance, there must be no water bottom, and air should be admitted. Where necessary drainage was a good investment if only to allow free excess of air. Contrary to a prevailing opinion drainage was often advantageous to dry soils more for the circulation of air than to carry off excess water. Subsoiling in some grounds was an absolute necessity. A bed of strawberries that had come under the speaker's notice was supposed to be dying of some mysterious disease, but upon investigation he found the strawberries were trying to grow on ground that had been waterlogged during the winter and showed a parched cracked appearance in summer. A drain was all that was required and the berries picked up wonderfully. PLANT FOODS. Plant food was present in the soil and in the air. In different places the natural covering of the earth shows a different analysis. Forest lands could be as superior to scrub lands. In New Zealand the soil was chiefly deficient in phosphates. Farmers used phosphates extensively, but never really exhausted the soil, because crops were rotated. An entirely different condition existed in gardens, where nature had not the same opportunity to return foods. Plants required chiefly phosphoric acid, potash, nitrogen, and lime. Potash was usually plentiful in clay soils. Sandy soils had little or none at all. Potash was important and gardeners too often neglected to use sufficient quantities. Nitrogen forced strong growth, but lended to a sappy stem, which was subject to disease. Potash, on the other hand, stiffened the tissues of a plant, making It better able to withstand disease. Mr. Taylor defined manuring as the making good of any deficient natural food, and, where intense culture was undertaken, manuring must be understood.

Nitrogen encouraged luxuriant growth, and lack of this element was shown In poor plants and stunted growth. Nitrogen must not exist in a free state to be of use to plants; but was found in combination with other substances. Nitrate of soda was useful in cold damp soils, but as it was easily washed out should be applied as a top-dressing only when required. Sulphate of ammonia reduced lime content and lead to acidity, but was not easily leeched. Heavy textured land was usually rich in phosphate. The appearance of red coloring on plants which should be green showed the lack of phosphate in the soil. Muriate of potash could be used with advantage upon all plants with the exception of tobacco, potatoes, onions and kindred families, but was not in general use. Sulphate of potash (kainate) could safely be used, as it was a low grade potash container, and gave excellent results on mangolds, beets, etc. Phosphoric acid was usually deficient in soils, so should be replaced when used up. It promoted early maturity and strong root growth. Basic slag was a good method of applying phosphoric, acid. Superphosphate was a most effective phosphoric manure for most soils, but was not so good as slag for light sandy soils. It was specially valuable for short rooted crops. Farmyard manure, plus lime and reinforced with potash, would usually supply any vegetable garden. Seaweed, when analysed, was almost identical with stable manure, but did not give such good results. Poultry manure was very rich and gave best service when kept away from lime. Dried blood was essentially a nitrogenoiis manure and underwent rapid fermentation in soil, but was not quick acting. Manures for turnips, carrots, beetroot, radishes, parsnips—principally phosphate with a liberal supply of potash, and a small amount of nitrogen. Artichokes, potatoes, onions, leeks, shallots—principally potash with a moderate supply of phosphate, and small amount of nitrogen. Cabbages, spinach, parsley, celery, asparagus, cauliflower—principally nitrogen with liberal supply of phosphate and small amount of potash. Peas and beans, melons, marrows, pumpkins, cucumbers, tomatoes —phosphates and potash with small amount of nitrogen. HUMUS. Green manure when first dug in was very acid and generated carbonic acid while decay- I ing. This impoverished the soil; but after the acid had passed away the ground becomes greatly enriched. Digging in green crops in late autumn was bad for the following crop if sown too soon afterwards. When repeatedly manured plots seemed to become exhausted they should be trenched for only the surface layer was fertile. If the soil was loose for a good depth trenching was unnecessary, as the chief advantage lay In allowing air into the soil, not in bringing bottom layers to the surface. DISCUSSION. Mr. T. W. Brown asked what length of time should elapse after digging in a late cover crop before a winter sowing should be commenced. In reply, . Mr. A. K. Cockayne said that generally speaking, from six to eight weeks would be sufficient. There was no known artificial humus so the gardener had to depend upon green manures or old haystack bottoms to provide humus. Without a doubt the best crop for this purpose in Taranaki was black barley. Mr. P. Webster asked concerning the value of blue lupin as a manure. Mr. Cockayne said that if sown before the end of December and dug under In March this crop made very good humus, but black barley was superior. If the gardener could spare the ground, red clover and rye grass made a good covering to be left for spring digging. Mr. Brown asked for particulars for making composite for potting plants. Mr. Taylor replied that the essential was something sweet and fertile such as turf off an old pasture stacked bottom upwards until the grass was dead. Leaf mould was also very good and next to that very old stable manure to which sand could be added to keep the soil open. When a plant was changed into a larger pot the-soil should always be rammed with a small wooden rammer. At the conclusion of the meeting a hearty vote of thanks was accorded the lecturer.