This section is from the book "The Gardener's Monthly And Horticulturist V20", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
"How often do you water your flowers ?" To ask this question, so puzzling to gardeners, is the general inclination of most non-professionals. I, myself, have little advice to give on the subject, but wish to say that if we were more inclined to reason, calculate, and to consult nature, that question would not be asked so universally. The point is to know when to apply water; this is something what no man has yet been able to describe. There are so many things to be taken into consideration, the variety and stage of growth of plants, the character of the soil, the season, the temperature, the situation, etc., which only the experienced can distinguish. But there certainly need not be much stress laid on the subject concerning flower beds. It is different to plants in pots, where their life depends on proper moisture. But allow me first to say a few words in regard to the general belief that "it will not do to water flowers while the sun shines on them, " even if it is at five or six p.m. Now, to water or sprinkle on the flowers is in fact, not good, whether in the sun or shade, at any time, and that is a rule wherever the plants are placed.
Growers of fruit under glass have to know this. "We need only call to our minds that if rains occur while Peach and other fruit trees are in blossom, it will impare the fructification; and it is my opinion that if pollen is washed off before properly developed, the petals, as being members of the system, might hang on, but a premature fading of the flower will be the consequence.
But let us return to the flower beds, I fear they are getting dry. The injury meant to occur to plants by watering in the sunshine is, that the water lodging on the flowers and leaves should become so hot from the effect of the sun, before its evaporation as to scald them. How far this is posssible, or in what latitude, I will not venture to state, but doubt that there is any danger of it in the Middle States, if in this country at all.
At the great Exhibition at Philadelphia, in 1876, the men that watered flower beds in the morning and evening, and the grass in the middle of the day, because other times were not sufficient, while the mercury marked 95° and 100°, were often told by visitors that the result would be fatal, but no such result could he observed. The real objection to it is the wasting of water, because a considerable quantity evaporates in the air, especially if done through a hose, and renders the work ineffective. This is plain to everybody, and we will find that if a syringe with a very fine rose is discharged in the air, on a hot day, little or nothing will fall to the ground.
When plants are watered, they should be. given it so freely that the moisture should be calculated to go some five or six inches deep. In this way the roots will work in the right direction and seek the moisture, while sprinkling a little on, now and then, causes them to linger near the surface. Thus the plants become delicate, and will flag after a few hours exposure to the sun.
Before watering, the ground, while there is room for it, should be stirred up with a hoe or stick roughly between and round the plants. If a pot is used, the water should be given heavy with the spout, and as soon as practicable the soil may be leveled with a small rake, which will prevent formation of crusts or cracks.
The evening is the best time for watering, because the moist beds will to a greater extent attract the night dew, and parts of the ground not well soaked through will have time to do so before the sun commences to again draw it out, in form of vapor.