Monday, March 31, 2008

How much water is too much

Will soil that gets too much water hurt your plants? Can you start
planting before the winter water dries up?

According to an Oregon State University article, when water fills up
air pockets in the soil, it shuts off the osxygen supply to plant
roots and microorganisms that live in the soil. The soil becomes
anaerobic, meaning it doesn't have any oxygen. After a few days most
of the oxygen is gone. And plants that need lots of oxygen get
stressed and eventually die.

But, it doesn't happen immediately. Most plants can survive temporary
saturation by water. It also depends on how deep the roots are.

Some simple actions can improve chronically wet soil.

First, use lots of organic matter in your garden. Organic matter
opens up the soil and allows water to move freely.

Next, in areas where there is standing water choose plants that handle
the wet well. For example, Ponderosa pine is much better than Douglas
fir in soggy soil.

Fruit trees require dry feet so plant them in berms, raised beds or
planters that keep the roots above the saturated soil.

If your soil stays wet in the spring, delay tilling and planting.
Working wet soil creates hard, impermeable clods, and seeds are more
likely to rot in cold, soggy soil.

Where there is runoff you may want to use structures to prevent
erosion. However, on level soil or where the ground is concave, you
may have to wait for the sun to dry up the soil.

Peg Herring. "Soils take a soaking in winter." Retrieved March 31, 2008 from