THE GARDEN.

Manawatu Standard, Volume XLIII, Issue 420, 10 June 1922, Page 7

THE GARDEN.

Notts arc published weekly under this heading, and readers interested in gardening aro invited to send in questions relating to matters upon which (hey wish export advice; answers will be published with tho weekly notes.

BLACK SPOT AND MILDEW. All rose growers know what it lot of damage is- done every year to their plants by these two diseases, and so perhaps they will like to hear what Dr. Sauer has to say on the subject in the hist rose annual, lie begins by saying that about four years ago ho knew nothing whatever about rose growing, and could not name any one variety. However, for health reasons ho had to give up his work and go in for something else; so he decided to go in for rose growing, lie says;—-‘ln tho Rose Annual for 1919 the paper read by Dr. Massey on ‘The Control of Black Spot and Mildew’ interested me. During tlie summer of this year 1 have carried

out experiments for the elimination ol these two diseases of the rose. 1 have two rose gardens about a hundred yards apart. Cue. is known as the Formal Garden, ami contains about seven hundred roses, all hybrid teas and pornettianas, with the exception of one bed of Lady Hillingdon. Tho other, tho ‘Note of Interrogation’ garden, contains fivo hundred bushes nearly all hybrid teas, with a lew pernettianas and hybrid perpotuals. Both gardens have trees in their vicinity, but the trees are not near enough for the roots to interfere with the rose bods. The gardens are if anything rather too well sheltered from wind, and they are entirely surrounded by an artificial backwater to the Thames. The soil is ol j the best, loamy clay lying on gravel, j In both gardens the bed's were made up | properly as directed by the books on | rose growing. And 1 may state as a final preliminary that 1 prune hard down to one or two buds; never more j than three. The experiments consisted in treating tho bushes in the Formal Garden with a mildew preparation prepared by S. McGredy & Son and those in the Interrogation Garden with finely powdered sulphur arsenate of lead, as recommended by Dr. Massey. Dealing first with the Formal Garden. Mildew i appeared in this garden late in July; Gorgeous and Chits. E. Shea wore the two first affected. 1 began spraying at once with McGmly’s preparation on all such beds as showed mildew, with the result that a weekly spraying completely eradicated the mildew after throe or four sprayings at most. On a few beds where mildew had not appeared preven-

tive sprayings were tried, and this proved effective, as no mildew appeared during the summer aiul autumn. A bed of Mine. A. Chatouay was allowed to become well infected, and three sprayings at weekly intervals completely cured the mildew. The general conclusion is that McGredy’s prepara- ■ tion is an efficient preventive and ' also an equally effective cure for mildew. The preparation is harmless, nqnpoisonous and colourless. It is easily prepared for use, and does not stain either plants or clothes; on the connary all plants sprayed looked clean and healthy, the foliage _ being improved and having a varnished appearance, Soft soap should be always added as it improves its adhesiveness. Seine of the beds of the more mildew resistant roses were not sprayed more than twice in the whole season. Black leaf .spot attacked six or seven plants in a bed of twenty-six Mine. E. Herriott in the early part of September. It is only fair to state that this bed had not boon treated with the remedy, as no mildew had appeared on it before the arrival .of the black spot. On the other hand a bed of Grange Colomb, which had black spot badly last year, was sprayed weekly and showed no trace of the disease at all. Tho preparation seems to act as a stimulant to the leaves. The bushes in a bed of Mrs Ambrose Riccardo in the two preceding years had practically lost all their foliage by September, but after spraying this year they wore in full hlooin

tight up to November frosts. The now

rose, Mrs Curnoek Sawday, scams to be more liable to mildew than any of the others, and last year did not "do well, hut this season, after being sprayed, was a great success. The plants in the Korina! Garden were a perfect joy to look at. Apart from their blooms, which wore almost perfect of their kind and very profuse, the wood ami leaves showed the perfection of health and strength. Now for the sulphur arsenate of load powder tried on the live hundred plants in the Interrogation Garden. Dusting with the powder was begun as soon as the first outbreak of tin* mildew showed itself in this garden. Owing to the very dry and sunny weather which lasted through the summer and autumn the powder remained on the plants for a long period before a new dusting was recptired. On the whole f should doubt if any plant had more than four dustings during the whole of the rose season. The result was practically a complete prevention oi both black spot and rose mildew. Black spot only showed on one very small plant of Rayon d’Or, which may have escaped the dustings. Black spot showed freely on some pillar roses growing on a wooden pole fence a few yards away from the rose beds. These pillars were not treated or dusted in any way. It appears that the sulphur arsenate of lead powder is in effect an almost, it not absolute, preventive of black spot. The dustings should be liberally supplied and renewed after rain or high winds. On mildew tho effect of the powder was also well marked. This remedy prevented the arrival of mildew and cured it after it came. To obtain this result the plants must he kept regularly under the iniluonco of the powder. I noticed that it rapidly reappeared after the removal of the powder by wind or rain. The use of the powder does not improve tho look of the planks, but on tho other hand it protects them, and they bloom until late in the season. As far as the treatment of mildew is concerned—preventive or curative—l prefer personally the use of MoOredy’s mildew preparation, it destroys mildew absolutely and vastly improves the appearance of the rose hushes. In spite of the heat amt drought of the past season, the roses in the Formal Garden made splendid growth ami their vigorous health and clean looks much impressed my rose growing friends. 1 have a strong suspicion that the continued use oi this preparation will protect the rose not only against the mildew, but also against other diseases of the wood and foliage to which roses are, heir. In conclusion, 1 may state that tho garden is well cultivated and eared for; tho beds are constantly worked with the Dutch hoe. in order to keep a line tilth on the surface. The roses had one good drenching of water during each of the months of May, June and July. They are manured once, in the beginning of April with cow and stable yard manure. The beds had a dressing of very fine slaked lime in the winter, and also a top dressing of some well rotted top spit that had been stacked for twelve months.”

REMARKS. If tlio above preparation is as good a» is claimed tor it one ul the worst

troubles of the rose grower is over. Every season we see beds depleted of their foliage long before it should bo so, and from Dr. Sauer’s remarks he evidently thinks that he combated both the mildew post and the dreaded black spot by its use. in another part of the rose another writer refers to this preparation as being a grand thing to keep mildew away from seedling plants. All those who have tried to raise seedlings know that one of tho worst enemies they have to contend with is mildew, and no matter how young the plants arc they seem to contract the disease, very often with fatal results. Although the plants may bo immune from it in after years they suffer from it in tho earliest stages of their growth. QUESTIONS.

J.M. says: “Would you kindly tell me, through the paper, tho best way to goriniimto macrocarpa seed, and about tho right time to sow it.” Macrocarpa seed is very easy to germinate provided the seed is good. A good I sample of seed will as a rule give about 50 per cent of fertile seeds, but the usual ratio of germination is very; much below this. In tho early spring when the days are getting warmer mix tho amount of seed you wish to sow with some red lead and a little kerosene to keep tho red lead on the'seeds. Then put the seed in a box of sand, mixing it up well together; water this and allow it to stand under glass until you I can see the tiny shoots appearing, ft is then time to sow the seed in the open ground, and to do this prepare! the soil in the same way as you would for an onion bod and draw flat shallow drills about six inches wide and half an inch deep; sow the sand and seed in this and cover up with about half an inch of fine soil. If the weather is very dry it is just as well to give the bed a good watering and then to lay some branches of manuka over it to j keep the hot sun oil. Unless the seed I is coated with red lead the birds will 1 eat it and nono will come up. As soon I as the first leaves appear above the ground take the covering away and the plants will take care of themselves, j Weeds must be kept down by hand j weeding and after the hot weather is over the young plants will grow very rapidly. PRUNING GOOSEBERRIES. J, 11. asks for information about pruning gooseberry bushes. Before you begin to prune a plant or tree of any sort you must understand something about its habits and where it

bears its fruits or Hewers as the case; may be. The gooseberry is one of; those plants that bear their fruit on the old wood several years old and also on the new wood that was made last spring .and summer. It cully pruning in this case is more of a thinning than anything else, if you examine a bush you will find that it has borne a crop on the old wood mi the spurs that' come out from it, but the crop to beborne on the wood of last season’s growth is of more consequence than the old wood. Every young shoot will bear fruit, but because the more young shoots a bush has it does not moan that the crop is going to be heavier. When once you reach the limit of the plant to carry a crop you are getting the maximum amount of work that you can out of that bush, but if you overstep this limit you will find that the crop will deteriorate. Avoid an overcrowded plant and cut to allow the suu and air to get to every part of the plant. Then again there is the operation of gathering the fruit to bo considered, and it should be cut so that the fruit can be gut without damaging the plant, ami without unnecessarily scratching the hands. If you have shaped up your plant so that this can be done you may lie fairly sure that you are on the right side. Long young growths should bo cut back a part of their length, according to their position and habit. Sometimes you will find that pruning has boon done in former years in such a way that the centre of the plant is a mass of small shoots and that it is impossible to get the hand down into tho middle of the plant. In this case these short growths must bo taken out; do not cut these high up or it will mean that more fine spurs will grow, but cut them right out close to the main branch. Shoots that are reaching the ground can be trimmed in such a way that they are well off the ground but still have plenty of room left to carry tho crop, THE VEGETABLE GARDEN.

The vegetable garden in a great many instances is the most neglected part of the grounds during winter

partly because it is the least attractive and partly because its owners do not

know what to do with it. There is one golden rule that should always bo observed and that is if the ground is unoccupied by any crop dig it up and leave it exposed to the elements to do what they like with it. Sun, wind, frost and rain all play their part, and all together they sweeten up the soil for the crops that are to follow. Even if the ground is hard when it is dug up under the ameliorating influences of the elements it will soon crumble up and when soil lias been deeply trenched a lot of nourishment is carried down to the subsoil which the plants will find later on. It has been computed by experiments carried out at Hothamstead iu England that more food is carried to the soil by the rainfall and frosts acting on them than anyone would think. The rain iu falling collects nitrogen from the air which is in turn turned into nitrates by the chemical action of the soil. It can bo safely said that all new vegetable gardens at least require lime in the soil and there is no time like the time present to do tins work. Farmers use lime for their fields at the rate of about two tons to the acre, which for garden purposes works out at the rate of four hundredweight to the square chain. There are few gardens of this size devoted to vegetable culture, but it is easy enough from this table to work out the amount required. We have found in practice that it pays to give a piece of ground where any of the brassica or cabbage family have been growing a good dressing of lime every year. The lime kills any likelihood of club root disease attacking any future crops. If the soil is going to' be limed it should be done at once and manuring be left until the lime has either been washed into the soil or dug in. If lime is sown on manure it sets free a lot of the goodness from the manure which is wasted, but at the same time if the manure is in the soil the lime may bo sown on top without any harm being done.