Install drain tiles to treat standing water

Q. A corner of my garden has poor drainage and I have lost a lot of plants there over the years. A friend told me to put in a dry well. What is a dry well and will that help?

A. A dry well is unlikely to correct your problem. It is simply a hole dug in the ground and filled with gravel. The hole will quickly fill with water while the surrounding soil remains too wet.

Any solution for your soggy conditions must move the water out of that area of the garden. There are different ways to do this depending on each site's conditions.

One possibility is installing drain tiles, which are perforated pipes buried beneath the soil. Water enters the pipe from the soil and flows down to a place where it can discharge into a retention pond or the storm sewer.

The drain tile pipes should be installed in the lowest area of the too-wet bed and slope down evenly to a lower point where the water can discharge out of your garden. The soil above the drain pipe should not be compacted or be heavy clay, which would prevent water from reaching the drain.

Use 4-inch-diameter perforated pipe made of PVC or flexible black plastic. Install No. 8 gravel or 5/8-inch roofing gravel around the pipe to help collect water and prevent silt from plugging up the pipe.

Another alternative is a French drain, which is a trench filled with gravel in which water can collect to flow away. It will help dry an area out providing that there is a place for the water to move to and that the trench is pitched properly to slope down to that place. Otherwise, like a dry well, the gravel-filled trench will fill up with water while the surrounding soil remains too wet.

If the wet corner is the lowest part of your garden and there is no lower spot to which the water can flow, you might consider adding drains that would run to a catch basin where water could collect. This is a more complex installation and might require a village permit to install. Since a catch basin has no outlet, you would need to add a pump to move the water up and of the area.

Catch basins must be cleaned regularly to keep the drainage system working properly. Debris will build up in the basin and eventually plug up the piping.

If you are unable to improve the drainage, try installing plants that are adapted to wet conditions. The Plant Information Service of the Chicago Botanic Garden (chicagobotanic.org/plantinfoservice) can suggest appropriate plants.

Tips for July

It's time to harvest fruit and vegetable crops. Pick them at the peak of their flavor. Younger plants and fruits are often more tender than those left longer. The length of time fruits and vegetables remain edible will depends on weather conditions. High temperatures hasten maturity.

It is important to handle harvested fruits and vegetables carefully.

Check the garden daily and remove any ripe, damaged or misshapen fruits or vegetables. To harvest those that are not easily removed from the plant, such as eggplant, cut the stem with a knife.

Harvest on a regular basis to encourage production. Many plants, such as cucumbers, okra and zucchini, will stop setting new fruits if mature ones are not removed.

Frequent rains have caused many shrubs to put on a lot of growth this year. Prune them as needed to keep them in the proper scale for your garden.

Since spring growth will be mostly hardened off by early July, there should not be much new growth when shrubs are pruned at this time.

For a more natural look, try pruning branches with hand pruners instead of an electric hedge clipper.

Make individual cuts at different heights throughout the shrub. Prune right above the leaves to help hide the cuts.

Careful pruning will leave the plants smaller but not looking "sheared."

For a more formal look, make cuts at the same height. Remove dead wood as necessary.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.