Standard garden soil may work fine for vegetables planted in the ground, but it does not work well for container gardens.
Garden soil will pack into a container, allowing water to pool around roots and preventing air from getting to them. Since plants need both water and air, a different type of soil mixture is needed for container gardening.
Packaged Potting Soil
Available at local gardening stores, packaged potting soil may work for container gardens. However, it may be too high or too low in organic matter, may include undesirable products and could contain chemical fertilizers.
Soil-less Mixes
Mixes like peat-perlite, or peat-vermiculite concoctions are too light for most container vegetable gardens. They do not offer enough root support for mature plants. Mature fall fruiting plants, such as broccoli or cauliflower can have rather large above-ground growth. This could cause them to topple and uproot. Heavy winds could also blow lightweight planters over.
Mixing Container Garden Soils
Container garden soil needn’t be sterile. In fact, any good soil has high levels of microbes. Sterile growing mediums may be a good business practice for nurseries, but for the home container gardener, compost makes excellent potting soil.
Add a small amount of sand, peat moss and another moisture-conserving substance, such as perlite to the mixture.
A Container Garden Soil Recipe
- Two gallons of well-screened compost
- Two gallons of peat moss
- Two gallons of perlite
Mix thoroughly in a large container or wheelbarrow.
Makes approximately six gallons of container soil.
- Peat Moss, also known as sphagnum peat moss, is a partly decomposed moss, rich in nutrients. It also has high water retention capabilities.
- Perlite is a volcanic mineral. When heated, it expands 12 to 13 times its original size. The heating process pops grains of the mineral just like popcorn. They form a granular, snow-white material. It is so light in weight that it weights only five to eight pounds per cubic yard. As a comparison, a cubic foot of topsoil weighs between 75 and 100 pounds. Perlite is sterile, organic, does not deteriorate and is a good medium for holding air and water in the soil. It also works as an insulator, helping to reduce extreme soil temperatures.
- Vermiculite is made from mica, a mined substance. It has much the same properties as perlite. However, much of the vermiculite on the market today comes from areas close to asbestos deposits. Asbestos has been ascertained to be the cause of mesothelioma as well as other health problems.
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Choosing a Site for A Fall Garden
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