Can You Reuse the Soil in an Earth Box?

Potting Mix

• Earth Box growing systems use a common mix of ingredients for their soil medium. The potting mix is composed of peat moss, vermiculite and perlite. Once peat moss has been dried out, it becomes hydrophobic and difficult to wet. Earth Box potting mix includes a wetting agent to make it easy for water to dampen the soil. Vermiculite increases the water-holding capacity of the potting mix and helps hold nutrients in the soil. Perlite makes the mix less dense and allows roots to penetrate deep into the soil.

Organic Mix

• Earth Box also offers an organic potting mix. This mix is the same as the normal variety but without the vermiculite. The organic mix also has an organic wetting agent. Standards for growing organically vary. It may not be necessary to have an organic potting soil in order to call your vegetables "organically grown." Since the organic mix does not have vermiculite, it will not retain as much water as the standard Earth Box potting mix. This means plants grown in the organic mix will need to be watered more often.

Reusing Soil

• Earth Box soil, organic or regular, can be used six to eight times. This means that the same soil can be used to grow six to eight crops of indoor vegetables. Depending on the climate where you live, this means the soil should last six to eight years. After eight years, the soil is worn out, and the peat moss, vermiculite and perlite have broken down. The soil's water-holding capacity has likely been reduced, and the wetting agent no longer works. It is fine to put this material in an outdoor garden, but it is no longer suitable for indoor growing.

Indoor Growing

• Keeping the right amount of water on indoor plants is essential. Because indoor gardens do not have deep soil, water is quickly depleted. Vegetable plants can get very large. When a large plant is growing in a small container, it may need to be watered every day. Over-watering is also a much greater concern than in a traditional garden. Due to the small amount of soil in an indoor growing system, it is more easily saturated. Saturated soil, if not drained properly, can suffocate a plant's roots. Always feel the soil to know if an indoor plant needs to be watered.