Solarizing your Garden

Here in Arizona we have a great tool in keeping our garden soil healthy and that is the sun. Did you know that in the hottest parts of the summer (July and August), you can take a break from gardening and it will help your fall garden grow better. It is through Soil Solarization. The benefits to your garden are that soil-borne pathogens and diseases are put under control, plant diseases, plant parasites and weeds are killed in the solarization process. It doesn’t hurt the worms; they just dig down deeper where it is cool.
Here are the steps to solarize your garden:

You need to get some CLEAR polyethylene plastic (I use 6 mil that I get in the painting department of the home stores). The longer you can leave the plastic the better but in the heat it will start to break down so I recommend 6-8 weeks.

Step 1:
Till your garden soil to 1 foot depth. Smooth and level out the soil and rid it of any leftover roots, weeds and dirt clods.

Step 2:
With a sprinkler or any other water source, saturate the garden to a depth of 3 feet or more. This could take hours but it is important for successful solarization. Then dig a 6-8 inch trench around the outside of your garden plot. Wet the soil again. Lay the plastic over the garden and trench, sealing the edges of the plastic in the trench with soil, rocks or anything that will make it virtually airtight. Let it bake for 6-8 weeks but make sure no holes get in the plastic to break the seal. You will see it “steaming” up and that is how you know it is working.

Step 3:

After 6-8 weeks remove the plastic. This is when I add 2-3 inches of manure and work it into the soil. Now I am ready to plant.

This really cuts down on the weeds you have during the winter. I haven’t needed to do any additional fertilization in the garden since I have started doing this each year.

The U of A Extension Service has an information sheet on their web-site on this process that you can download and print.