- Prepare the soil: You know the drill. Clear debris/weeds, Add amendments, Rake to remove any trapped "air pockets".
- Water thoroughly. This creates 100% humidity. Without the humidity it's like trying to steam your veggies without any water...it just doesn't work.
- If your working with a ground level bed then dig a trench about 6-8 inches deep around your garden. If your working with a raised/framed bed usually you have about that much soil above ground so you can skip this part.
- Cover with clear plastic (6 to 8 mm) overlapping the trench/framed sides. Fill in the trench with soil weighing down the plastic while pulling it as tight as possible. In a raised/ framed bed you can also use soil/rock to weigh down the plastic or you can staple it to your frames. Remember the key to success is a air tight covering.
- Patience....Patience! 4-6 weeks of sunshine and you have healthy soil. No matter where it came from.
This process is cheap and easy. Although if you have a patience problem like I do...Good luck. Soil Solarization has many benefits. According to one of my long time favorite books: Storey's Basic Country Skills "It kills insects, nematodes, harmful fungi, weeds seeds, and eliminates plant diseases. At the same time helpful microorganisims within the soil apparently benefit, possibly from lack of competition. Soil that has been solarized allows plants to draw on nutrients, especially nitrogen, calcium, and magnesium more readily. Seeds germinate more quickly. Plants grow faster and stronger, often maturing earlier with substantially higher yeilds, than in unsolarized soil." All I know is that I can't ever remember having any of my gardens infested with anything. I generally never have to worry about bugs or disease. So does it work? I'll let you try it and judge it for yourself.
I love this book. Like I said it's one of my all time favorites. But if you don't own an old beat up copy like I do...Try The Green Man (warning it's a PDF) for some good soil solarization info.