THE GARDEN

Manawatu Standard, Volume XLIII, Issue 1388, 21 November 1918, Page 2

THE GARDEN

SOIL STERILISATION. The subject of soil sterilisation has been receiving 'considerable attention during the past few years. It was found that rich artificial soils with a high water content and summer temperature used tor pricking put plants is a particularly favourable medium lor the growth and development of certain forms of minute life, and these gradually make the soil unhealthy to the roots of crops. When the soil is sick it is useless lor greenhouse work, and consequently has to be changed, vvlneh sometimes means considerable expense. Now if this soil can bo cured of the sickness, and health restored to it, it may bo used again and again. Some of the organisms frequent in sick soils are animal creatures such as the minute worms that produce the sleepy sickness in tomatoes. But if these ueic the only inhabitants of the soil, while they would still induce disease, thoj could hardly bring about that peculiai soil condition known as sickness, roi a proper understanding of the subieci wo must know something about the soil, particularly what the condition! are that constitute fertility. The soi is not a mere mass of inert material, 01 the contrary it is teeming with life Every tiny particle is surrounded by s tliin film of water, and as these film: are in touch with one another, it lot lows that a vast sheet of water extend throughout the soil. In this soil un countable numbers of bacteria live am move; also we have another kind o life that feeds upon these bacteria jus as animals feed upon grass on the sur face of the soil. The bacteria plays i very important part in the nutrition o crops, they break down the organ! matter of manure and liberate ammo nia; others, again, convert the ammo nia into nitrates, and there are other again that collect nitrogen from the ai and store it in the soil. Without thes useful beings the soil would ho barton the food might ho there, but ther would ho nothing to liberate it. J

has boon proved that under greenhouse temperature the growth of the microbes that feed on tho useful bacteria increase so enormously that they deplete tho stock of tho useful ones; so much so, that their efficiency is impaired and the soil, though rich, fails: in other words, it becomes sick. Numerous experiments wore carried out, including the use of lime and heating soil, but at Ilothainstead, in England, it was found that tho sumo results could bo got by the use of antiseptics. The experiments published from the work oi .Russell and Hutchinson in 1907 are most interesting. By heating the soil from 95 degrees Cent, to 100 degrees Cent, it is partially, not wholly, sterilised. The animal population is destroyed, but not tho bacterial, at least not entirely. By the use of antiseptic, such as carbon bisulphide or formalin, the injurious microbes are killed, but the only oliect upon tho good bacteria is to throw them into a state of rest, and, when the volatile antiseptic escapes, as it will in time, the bacteria awake and renew their activities. So that after the partial sterilisation of the soil, either by heat or antiseptics, tho bacteria become active again when they lind themselves in surroundings entirely freed from their voracious enemies, and thus they feed, grow, and multiply at an amazing rate, and at the same time liberate a great quantity of food to the growing crops. Tho partial sterillisatiou of soil is practised very largely in tho United States for growing cucumber and lettuce crops for early markets. It has been found to give quite a third more growth and to amply repay for tho trouble undertaken.

SNAPDRAGONS. In tho antirrhinum, or snapdragon as it is most generally called, we have flowers of great beauty and curious form, plants of free-flowering habit and excellent form. Their flowering is continued over such long periods that they aro indispensable in any garden. Snapdragons have been known lor so long that they are apt to bo overlooked when making up a list for our gardens. Howover, they aro easily raised from seed, and seed from which a big percentage will come true to colour can bo bought. In tho United States of America there nro several specialists who have taken up tho work of improving the colours, and have succeeded in raising “something worth while,” as they say over there. They have not only got plenty of different colours, but have also got some with flat and crinkled hoods which look very well amongst the other forms. To grow them well there aro a few things that aro absolutely essential, such as well drained soil free from coarse or fresh manure. They do not seem to mind how poor the soil is or how dry, and aro especially useful for planting alongside houses and places that are sheltered from rain. Although they aro of strictly perennial duration, tho most favoured method is to treat them as annuals or biannuals, preferably as annuals. For this method seeds aro'usually sown about this month so that good strong plants will he ready for planting out in March and April. These plants will begin to bloom early in tho following spring, and when they have done their best, and before they get straggly, they can be replaced with plants from seed sown about May or Juno and pricked out during the winter. It is essential at all times that they must have good drainage. If this is not attended to there is always a chance that a lot will damp off. If you wish to treat tho plants as biennials they must have tho seed pods picked

(Specially written for “Standard.”) Noras are published weekly under thin heading, *nd ltMA rwreH in gardening are invited to send in question* relating to matters upon which the* wksb expert advice; answers ivdi I'-j published with the weekly notes.

off as soon as the (lowers have dropped, otherwise they will begin to ripen their seed and their days of flower production will ho over. Snapdragons an also easily grown from cuttings if you have a small frame which can be closed down tight until they arc rooted. When rooted admit air and gradually harden off. As, however, seeds come fairly true, and plants raised from seed an much more vigorous than those from cuttings, few caro to bother with the latter.

SWEET PEAS. A correspondent says: “Would you kindly explain why some of my sweet peas arc coming quite a different colour this year to' the particular varieties they were saved from ? 1 grow them in clumps by themselves especially for the purpose of saving seed from thorn, and yet in some cases they seem to have become mixed, and 1 am sure that none of the seed was mixed when it was saved.” Vour letter has been submitted to a raiser of sweet pea seed and ho says: “Most probably the plants were nob rogued, that is, they did not have the plants that were untrue to typo pulled out when they were in blossom. I have been saving seed for quite ten years now and have very seldom found that pollen lias been carried from one plant to another at the right time, but I have found that if seed is saved from rogues that quite 75 per cent is inferior to the type it was saved from. On the other hand, I believe that hand fertilised seed is superior to a plant that is self-fertilised, and am carrying out some experiments this season with the idea of checking this opinion. If the natural laws were more perfectly understood I, perhaps, could give you a more lucid explanation, hut in the meantime tell vour correspondent to rogue thoroughly.”

THE GERBERA. It is a wonder that gerberas arc not more grown than they are; perhaps it is because they are not understood. It is not every kind of soil that suits them, but by making up a. piece and draining it thoroughly they can he grown almost anywhere. The soil that suits them best is one that is fairly light and loose and goes down to a good depth. '1 hey aro very deep-rooting plants, and if they aro allowed to will penetrate into the" soil anywhere up to three feet ; one of the great causes of failures with them is wet feet, which they will not stand. Once a clump becomes thoroughly settled, leave it alone; it will go on increasing and flowering tor a long tiino before it need be taken up and broken to pieces. Another cause of failure is the lavish use of manure. Ground that has been manured for some previous crop will suit them very well, but no fresh manure should be put near thorn when they are planted. The best time to plant is either very early or very la to in the season, and when they are sot out bo sure to cut away the tops. If these aro lott the chances aro that the plant will die, but if cut away they soon send out new loaves and growth may bo safely assumed to have begun.

VEGETABLES. There is an old saying “when it is dry prepare for rain,” but with gardening the adage could bo conveniently reversed “when wet prepare for dry.” That is what the gardener lias to do. So far wc have had a wet season, a very wet one, but for all that we do not know bow long it is going to continue. It may take tip at any time and come on very dry. The best way to prepare, .for it is to cultivate the surface soil to a depth ol two or three inches and keep it in a perfect state oi cultivation all the time. Then when it. does begin to get dry the sun has not got the power to draw the moisture out of the soil, and the only way it can get out is through the plants themselves by transpiration. The hoe is the most useful article in the garden at the present time and those who neglect to use it are not gardening they are only playing. It is quite a common sight to see people using the hose on their gardens alter a day or two of fine weather, but if they only know the harm it does they would chop it up and burn it. Use the hoe and the hose can be left alone. Plant out marrows and pumpkins as soon as you can now or it will soon be too late. Sow peas for succession light up till Christmas. They will conic in when oilier tilings nre plontfful, but as they are always appreciated they will not be wasted. French and butter beans should be sown every three or four weeks, giving plenty of room between the plants. The oldfashioned way of sowing close together is not a profitable one, but it eight inches to a foot is allowed between the plants the crop will be one that is worth picking and the plants will g° on cropping for a much longer period. Sow lettuce seed in well prepared and manured soil. It can hardly bo too rich for this vegetable however much manure there is in the soil. After the end of this month stop cutting asparagus head and allow the plants to run to seed and form new crowns for next year. Give apple and pear trees a second spraying ivith arsenate ol lead and with a brush and some oil go over the trees and paint out any spots that show signs of woolly blight. I Ins is the most effective method of dealing with this blight and does not take very long to do.