Remember, if you water your plants in excess, you are wasting water, as plants transpire the excess water they absorb into the air through their stomata or leaf pores. Excess watering also causes water logging in the soil, which could damage roots and interfere with aeration within the soil. In fact, horticulturists say that over-watering is the most common reason why the saplings of novice gardeners do not take off.
Most herbaceous plants do not survive water logging. “With herbaceous plants like tomato, bulbous plants, etc, a mug of water per pot per day suffices. Water just enough to moisten the soil. If it is especially hot and dry, or in non shady areas that are totally exposed to the sun, water the herbs twice a day. Herbs are not deep-rooted plants and they don’t need the water to leach into deeper soil”, advices Prof. D. Narasimhan, associate professor, Department of Botany, Centre for Floristic Research, Madras Christian College.
What about shrubs and trees? “With shrubs like rose, jasmine, etc, we could water them just once in one or two days. You don’t have to water well-grown trees at all, except in the case of arid conditions or prolonged drought. Until the trees are about a year or two old, or until they have grown large enough, you might want to water them about once in two days. Only in hot summer do we need to water growing trees daily. And of course, as the summer softens and the rainy season steps in, tone down your watering further,” Prof. Narasimhan recommends.
These are only general guidelines though. We need to take a commonsensical approach, and water as per need, rather than as a cast-iron routine. It is a pity that many gardeners compulsorily hose plants and even the sidewalks around with so much precious fresh water, when all the plants need is just a fraction of this water. The water retaining capacity of the soil also has to be considered, with the ambient atmosphere and weather. How much you water matter, and when you water matters too. It is advised to water before seven or eight in the morning or after five in the evening, when the sunlight is gentle and the soil is cooler.
And finally, remember, plants enjoy a rain shower, while a waterfall can pin them down! It is best to sprinkle water on the plants, rather than pour water on its soil bed. Water can be hand-sprinkled, or a spray-can may be used. By sprinkling or spraying water, we also ensure that the dust settling on the leaves gets washed off leaf surfaces, leaving their pores unclogged.
