New plants need water at root ball

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I visited some friends last week who had planted a new lawn this spring and were having some problems with azaleas in a natural area out back.

There were about six shrubs. Two were dead and a third was getting close. The lady of the house was afraid they were getting over-watered because they water the grass three days a week.

I went back to the azaleas and started probing.

The first thing I looked for was whether too much quick-release fertilizer had been placed on the root ball. I didn't see any.

Next, I checked the planting depth. Planting too deeply can kill a plant, but the depth was fine.

Since the azaleas were already dead, I pulled one from the ground. What I found was that no roots had grown from the original root ball and it was dry as a bone.

This was on a Friday and it had been watered on Wednesday. The lady thought it was getting over-watered, but only one sprinkler head (from a rotary type) hits the azaleas when the sprinkler is running.

I ask homeowners with newly planted trees and shrubs that are dying if they are watering them, and most of them tell me, "Yes, my sprinkler hits it."

In most cases, though, sprinklers never run long enough to wet the entire root ball.

Think about where the roots are on that azalea (or any other plant) during the first month. Ninety-five percent of them are still growing in the root-ball potting mixture, just as they were back at the nursery.

The azalea roots don't begin exploring the surrounding soil until the plant has become accustomed to where you planted it. That means you should apply water at the plant's base for the first month or so.

Hand water slowly with a hose. The small stream of water will saturate the root ball without washing away the soil.

The laws of physics say that water moves from coarse soil (the potting soil) to fine soil (natural earth), and not the reverse. All of our soils, from the sandy types to clays, are sucking water from your azalea's root ball.

One thing that can really help here is breaking up that root ball when the azalea is planted, even though it may not be pot bound. Break up all that potting mixture and mix it with the backfill soil so you will not have that difference with what is in the root ball and the native soil.

If you hire someone to plant for you, ask them to break up the root ball.

After the plants are in the ground for a month, water under and around each plant. The roots will accelerate their growth and will be encouraged to explore the surrounding soil.

Many plants from nurseries will have had some slow-release fertilizer placed in the root ball, or the fertilizer may have been placed in the hole at planting. If this is the case, you may not need to fertilize for about three months.

If none was used at planting, apply a water-soluble fertilizer such as Miracle-Gro, Peters or Fertilome at half strength.

New leaves will appear, photosynthesis will increase and the roots will elongate.

If no leaves are being produced, something is wrong.

Summer is a transition time for shrubs. They should be able to find their own water in the soil and tolerate a few dry days without wilting. You may need to keep watering during a drought, but don't water every day. This makes the plants too dependent on you, and in many cases in poorly drained areas can lead to root rot, which is just as bad as a dry root ball.

Sid Mullis is the Director of the University of Georgia Extension Service Office for Richmond County. Call him at (706) 821-2349 or send e-mail to smullis@uga.edu.


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