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Spraying Don'ts: Watering

WATERING OF PERENNIALS. Watering must be attended to, especially during dry spells. One good soaking a week is much more valuable to plants than many light sprinklings which do not wet the soil to any appreciable depth. On sandy and very light soils it will be necessary to water thoroughly every day or every second day during the dryest part of the season. Where it is not possible to water all the plants thoroughly at one time, divide the beds into sections and water the various sections in rotation. Watering in the later afternoon or evening hours has a more lasting effect than during the hotter portion of the day. Watering can be overdone as it can be carried to the point where the soil becomes water-logged and will consequently sour. Too much superficial watering of open-ground plants induces surface rooting which is not satisfactory, as such plants do not have access to large stores of food, and consequently cannot withstand drought successfully. Transplanted perennials should be watered thoroughly and left alone a few days till they become somewhat established.

The statement is sometimes made that water from wells is too cold to be suited for watering plants, and also that such water often lacks chemicals which serve as plant food. On the contrary, successful gardeners often water plants at midday on hot summer days in order to gain the cooling effect of the water when it is most needed. It is also believed by some experienced observers that water falling on the soil reaches the soil temperature very quickly after being absorbed and in all but a negligible number of instances, before it reaches the roots of plants. With regard to the question of the amount of plant food contained in water from a deep-driven well as compared to the amount found in surface water such as that flowing in a creek or river there seems to be little reason to think that water from wells is lacking in plant food to such an extent as to make it less valuable than surface water. It is now agreed that surface water contains more solid matter in suspension while subterranean water has its load of solid matter in solution. Therefore the plant food which occurs in water from a driven well differs from the plant food found in river water merely in being more likely to occur in solution rather than in suspension. The water which is taken from artesian wells is not always sterile and often contains nitrates in large quantities due to the reduction of the nitrates which occur in deep layers in the soil. When this water is used for irrigating the surface layer of the soil, the nitrifying bacteria MAINTENANCE change the nitrites back to nitrates. In regions rich in humus, ground water often contains organic as well as inorganic matter. Well water may and often does contain plant food which is very valuable in the form of nitrates or ammonia.

REMOVING SEED PODS AND GENERAL CARE. Summer care of perennials consists of removing seed stems and dead flowers. It is extremely important to remove dead flowers at once, as formation of seeds weakens a plant. And with many plants, such as the larkspur and foxglove, new flowers also will be produced if the old flowers are removed immediately after blooming. There is a considerable difference of opinion concerning the general maintenance of the larkspur. Some persons think that the stock of this plant should be cut down to a height of four inches to six inches immediately after flowering, other persons feel that it should not be cut to a height of less than twelve inches to fifteen inches. The author's personal experience has been that if these plants are cut back immediately after flowering to a height of four inches to six inches new shoots will be developed which will not attain the height of the original plant but will develop excellent flowers during the latter part of September. Support tall-growing plants with neat stakes. In this class are asters, boltonias, and larkspurs. Do not delay the staking until the plants have begun to fall over. spaces among plants in a border should be filled with annuals, if necessary, as this will not only improve the general effect but help also to keep the ground shaded and cool, and provide bright spots of colour after the first flush of bloom among the perennials is over. Bare spaces may be filled by bringing in plants from a reserve garden where they may be held in pots. New varieties of perennials and biennials should be propagated and transplanted to the bed or border to replace plants that run out or begin to fail. Seedlings will spring up from many plants, such as anemones, marguerites, hollyhocks, and campanulas, when seed pods are allowed to form. Such plants can be used to fill up open spaces.

Bare DISEASES OF PERENNIALS AND CONTROL. Perennials, taken as a class, under fairly favourable conditions are not particularly susceptible to disease. In general, when diseases attack perennial plants, the safest thing to do is to throw them away. Aphis and minor insect troubles may be easily controlled by spraying.

The following plants, if attacked by leaf spots or mildews, may be saved by fungicides (See Page 77):

Alyssum (mildew).

Anemone (root decay and rust). Destroy affected roots. Aquilegia (mildew and black spot).

Campanula (red and brown rust). Keep away from pinus rigida. Chrysanthemum (leaf spot or powdery mildew). If rusted, plants should be destroyed.

Convallaria (stem rot). Burn affected plants.

Coreopsis (mildew).

Delphinium (black spot on leaves). Remove and burn.

Ferns (tip blight).

Hollyhock (leaf spot). If attacked by rust or anthracnose destroy the plants. Iberis (club root). Use lime in soil.

Papaver (mildew).

Peony (stem rot, leaf spot, botyrides).

Phlox (leaf spot and powdery mildew, and stem canker). Sedum (leaf spot).

Thalictrum (red spot).

Veronica (leaf disease), (leaf spot).

Violets (leaf spot and leaf blight).