VINES UNDER GLASS.

New Zealand Herald, Volume LXVII, Issue 20560, 10 May 1930, Page 5 (Supplement)

VINES UNDER GLASS.

NEED FOR ATTENTION.

Vineries in which late grapes are still hanging will, from this time onward, require extra, care and attention to keep the berries in a sound condition. The most important thing in keeping late grapes is to have the berries thoroughly well coloured and ripened, and to keep a fairly dry atmosphere in the house. Up to the past week there has been little difficulty in maintaining a fairly dry atmosphere, but with the change to moist weather, dewy nights and colder temperature, mouldiness in some of the berries is almost sure to take place unless artificial means are used to exclude the moisture. Where artificial heat can be be applied there will naturally be less risk of loss through decay of berries, but where this is not practicable and where the floor of the house is composed of soil, the evaporation in moist weather is excessive, and decay in

berries is almost certain to result. If on the other hand the floor of the house, as so frequently advised, lias been covered with concrete or ashphnlfc it can l>e kept comparatively free, from evaporation, and there is not the same risk of excessive moisture. The hunches in any case, 'should be frequently looked over, and any showing signs of decay removed. As soon as the vines are stripped of their fruit, war should be waged upon any pests that have attacked the vines or fruit. Few vineries escape the attack of some pests that cause considerable trqjuble and loSs to the vino grower if left unmolested, and it is during the autumn, when the wood is fairly matured, that stronger measures can be applied than would be safe during the growing and fruiting season. % Indoor grape culture is too expensive an undertaking to risk failures and loss through neglecting to uso every possible means of keeping under control injurious insects and diseases. Although it is almost impossible to eradicate the pests in one season, after they have established themselves in the house, much can be done by fumigating, spraying, and by cleaning and painting the vines, as well as the whole of the woodwork and trellises. The protection of the foliage is an important matter and no effort should be spared to keep these free from pests and in a clean, healthy condition until natural decay takes place with the return of the sap. In many cases, after the fruit is secured little or no• attempt is made to destroy these pests, with the result that the foliage becomes sapped of its vitality and fads prematurely. With such pests as mealy bug, thrips and caterpillar, fumigation with cyanide is effectual. With red spider, however, fumigation has little, if any, effect. This is a very troublesome insect and if allowed to go unchecked it soon injures the foliage and checks the vitality of the vines. Its attack is invariably the result of maintaining too dry an atmosphere. It cannot thrive in a moist temperature, although when once it has established itself in the house, it is seldom eradicated in one season. The best remedy for the destruction of these minute leafsucking pests is the free use of dry sulphur. The sulphur requires to be put on with a fine distributor so that every portion of the foliage is well dusted. As soon as the vines are stripped of their fruits free ventilation should be given and the vines exposed to the weather as much as possible, though every care must be taken to protect the foliage from injury. While this applies to all vines it is especially necessary with the latest varieties. The difficulty generally experienced with these is to have (ho wood ripened sufficiently early so that the vines, after pruning, can have a reasonable season of rest, and still be in the condition lor starting early in the spring.