How to Reuse Old Potting Soil
- 1). Build the solarization tent. Lay a sheet of black plastic on a flat, solid foundation. Lay a wooden pallet on top.
- 2). Place the old potting soil in piles, pots or bags on top of the wooden pallet. The soil should not be more than 1 foot deep. Water the soil to moisten it thoroughly.
- 3). Lay a sheet of clear plastic on top of the soil. Seal all the edges of the clear plastic to the black plastic using double-sided, heavy-duty tape to make it air-tight.
- 4). Tent a second layer of clear plastic sheeting on top of wire hoops. Seal the edges of the second clear plastic sheet to the bottom plastic sheeting using the double-sided tape.
- 5). Pry open a corner of the plastic sheeting and insert a thermometer into the soil to check the temperature every one or two days. After the soil achieves and maintains a temperature of 140 degrees F, you can remove the soil and use it.
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