Be cautious when choosing containers for growing food. Plastic pots are made from chemicals that break down under heat, duress or time, leaching into the soil and ending up in your food. Opt for containers made from natural materials such as clay, ceramic or metal. If you must use plastic, check the recycling codes found on the bottom of the pots and follow this guide to select the best types for growing food.
Safer:
1 (polyethylene terephthalate, PETE or PET)
2 (high-density polyethylene, HDPE)
4 (low-density polyethylene, LDPE)
5 (polypropylene, PP)
Avoid:
3 (polyvinyl chloride, PVC)
6 (polystyrene, PS)
7 (polycarbonate, PC)
–Source: Grow Great Grub: Organic Food from Small Spaces by Gayla Trail