Watering is a subject that seems simple and straight forward, but it actually has many nuances. How, when and why you water your plants will have a major influence on their success. Here are a few tips on watering. For a better understanding of the subject, refer to our information sheets Watering Basics for Indoor Plants.
• How much water a plant will need varies greatly as to type of plant, whether it is established or newly planted, the weather conditions, the wind, the soil type, the soil drainage and more.
• For almost all plants, a deep soaking followed by enough time for the soil to dry out slightly is ideal.
• Frequent light watering is not good for plants. It encourages shallow root growth. That's why irrigation systems designed for the lawn are seldom adequate for landscape plants and if they aren't set up and operated properly, they can actually be harmful to a lawn too.
• Feel the soil before watering and don't be deceived if the surface is dry.
• The outward signs of too much water are wilting and yellowing leaves, especially those in the inner areas of the plant. Signs of underwatering and overwatering are similar, so check carefully.
• Whenever possible, plants should be watered early in the day.
• The amount of water that falls on a given area can be measured by setting out several shallow, straight-sided containers such as tuna cans.
• Mulching with an organic material such as shredded bark minimizes evaporation and weed competition, reducing the amount water you will need to provide your plants.
• Avoid sprinklers that put out a fine mist - too much is lost to evaporation.
• Avoid watering directly from a hose. Average soil can only absorb about a half inch an hour.
• Native plants usually require less water than non-natives and exotics.
• Healthy plants need less water than stressed plants.
• Bluegrass needs to stay evenly moist to do well. But if you have a lower-maintenance lawn with fine fescue and perennial rye, an inch a week will be much more than the lawn needs for health.
• Frequent, shallow watering encourages poor turf root development and often leads to bare spots and disease-prone grass.
• In average soil, established trees and shrubs need an inch of slow rain every two to three weeks.
• Newly planted trees and shrubs need an inch of water every week, ideally split between two waterings.
• The majority of the roots that absorb water for an established tree or shrub are outside the dripline where nature would provide rain. That is where you should water.
• Plants need more water during the first half of the growing season than they do later.
• Plants that fruit, such as apple trees, need more water while fruit is developing.
• Vegetables need about an inch of water each week.