What can you use to retain moisture in soil for a long period of time?

Answer 1

Mulching is key to retaining soil moisture.

Soil loses moisture quickly through evaporation. Moisture in the top layer of soil gradually disappears under direct sunlight, and will dry out even quicker in windy weather. This top layer moisture comes and goes with the weather, but deeper down moisture remains for a long time because there is no way for it to evaporate. Roots of plants that go deep, such as trees, shrubs and some large grasses are adapted to tap into this deep moisture during the dry season.

The term "mulch" describes any material you spread on the surface of the soil. Mulch remains on the surface unless it decomposes, is tilled in or replaced the following season. Because mulch materials such as pine needle straw, ground bark, wood chips or wheat straw do not quickly decompose, they are desired mulches that remain in place for a long time, sometimes for many years.

A thick layer of mulch (about 2 inches thick) spread around your plants functions in different ways to help trap soil moisture so it is available to plants.

1. Mulch blocks light to the soil surface which prevents weeds from germinating. Weeds would otherwise consume surface moisture quickly.

2. Mulch provides an cover over the soil that prevents direct exposure to the sun's rays. This reduces and even eliminates sun generated evaporation.

3. Mulch is thick enough to act like an insulating blanket to keep the root zone soil cooler. When exposed soil heats up it can seriously increase evaporation and stress plant roots, particularly if they are shallow.

4. Mulched soils don't crust over so any water applied goes directly into the root zone. Moisture available at these depths is the key to survival for most species from desert environments around the world.

Answer 2

One can add moisture to gardening soil by watering the garden. Another way to retain the moisture in the soil is to buy a soil with specific properties to keep moist for longer periods.