Should You Use Soil Solarization?

Debbie Roland, Master Gardener

It’s only June and I’ve already pulled what seems like a million weeds out of flowerbeds, the garden and even the cracks in my sidewalks and driveway. While cruising the internet for a solution I ran across an article about Soil Solarization on https://aggie-horticulture.tamu.edu. Click on the vegetable tab to get more details on the study used in this article.

Solarization is an environmentally friendly method of using the sun’s power to control weeds and pests. Cover the ground with a transparent plastic and the sun will heat the soil to temperatures that kill bacteria, fungi, insects, nematodes, mites, weeds, and weed seeds. Start with weed-free soil, plenty of water, and enough plastic to completely cover the weed free area you will need.

· Clear the area of plants and debris.

· Water the soil deeply.

· Cover the area with clear plastic (such as 1 to 4 mil painter’s plastic). Don’t use white or black plastic; they don’t allow enough heat to get to the soil.

· Bury the plastic edges in the soil to trap the heat.

· Leave the plastic in place for at least 4 weeks in the hottest part of the summer. This will give you time to plant your fall garden.

· Remove the plastic.

· Spread compost and till the soil. Don’t skip this step since solarization kills all organisms, even the beneficial ones. The compost will replace the beneficial organisms.

Your garden is ready for planting.

TIPS: Solarization works best when there are no air pockets between the plastic and the ground. Be sure there are no holes or tears in the plastic. Digging a shallow trench around the edges may help. Place the edges of the plastic in the trench and cover with soil. With the West Texas winds it may also be helpful to place a few rocks or bricks on the plastic.

Gardeners can use solarization to significantly reduce weeds long and short term.

If you have questions, please call the AgriLife office in Odessa at 498-4071 or in Midland at 686-4700 for more gardening information. Additional information is available at https://aggie-horticulture.tamu.edu and westtexasgardening.org.