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How to effectively control weed growth?
Solar Soil is a new, scientifically proven, old-fashioned, chemical-free method of weed control. Sun exposure isn't a new weed control method for organic gardeners, who have been using tarps for years, especially in hot climates. Scientific experiments show that covering prepared metal raised garden beds with plastic for a few weeks before planting can reduce weed stress on subsequent crops, even in cooler climates such as the Northeastern United States.
What is sun exposure?
Sun exposure, including covering the soil in metal raised garden beds with clear plastic, tarps with black plastic can be counterintuitive and less effective at suppressing weeds. Both methods raise soil temperatures enough to kill dormant weed seeds. Weed suppression was found even at lower temperatures. Higher temperatures may promote "suicide germination," where seeds germinate but fail to grow under plastic.
How to dry your soil?
The sun is most effective on moist soil, which conducts heat better. Wet seeds are also more susceptible to heat. You can enhance the effect with two layers of clear plastic or one layer of clear plastic covered in black. The best combination of plastic sheets and length of time under plastic may depend on your local climate. But plastic should be used after the garden bed has been prepared and should sit for several weeks. This means it should be done after the first thaw of the soil, but before the average date of the last frost. Alternatively, you can prepare your garden beds in the fall and bask in the sun throughout the winter.
Gardeners with the time and ability may opt for more labor-intensive natural methods of killing weeds rather than buying polyethylene boards that may not be recycled when they are no longer available. But for those facing perennial weeds or converting neglected lawns into new metal raised garden beds, an alternative to soil sunlight may be chemical solutions. For them, there are ways to minimize the impact of plastic exposure. Used greenhouse plastic is available. If that's not an option, buy thick plastic sheeting instead of film. Gardeners can remove thicker plastic before planting and reuse it for years. If you can recycle plastic in your community, do so. Otherwise, dispose of the plastic properly once it becomes brittle and starts to crack. Sending chunks of plastic to landfill can be troublesome
What is sun exposure?
Sun exposure, including covering the soil in metal raised garden beds with clear plastic, tarps with black plastic can be counterintuitive and less effective at suppressing weeds. Both methods raise soil temperatures enough to kill dormant weed seeds. Weed suppression was found even at lower temperatures. Higher temperatures may promote "suicide germination," where seeds germinate but fail to grow under plastic.
How to dry your soil?
The sun is most effective on moist soil, which conducts heat better. Wet seeds are also more susceptible to heat. You can enhance the effect with two layers of clear plastic or one layer of clear plastic covered in black. The best combination of plastic sheets and length of time under plastic may depend on your local climate. But plastic should be used after the garden bed has been prepared and should sit for several weeks. This means it should be done after the first thaw of the soil, but before the average date of the last frost. Alternatively, you can prepare your garden beds in the fall and bask in the sun throughout the winter.
Gardeners with the time and ability may opt for more labor-intensive natural methods of killing weeds rather than buying polyethylene boards that may not be recycled when they are no longer available. But for those facing perennial weeds or converting neglected lawns into new metal raised garden beds, an alternative to soil sunlight may be chemical solutions. For them, there are ways to minimize the impact of plastic exposure. Used greenhouse plastic is available. If that's not an option, buy thick plastic sheeting instead of film. Gardeners can remove thicker plastic before planting and reuse it for years. If you can recycle plastic in your community, do so. Otherwise, dispose of the plastic properly once it becomes brittle and starts to crack. Sending chunks of plastic to landfill can be troublesome