Soil

Potting Soil and other best soil amendments

The most important element in your house plant’s environment is the soil.

You can buy commercial potting soils of excellent quality at any garden store. The truth is, most potting soils don’t contain soil at all, but well-rotted compost mixed with a large quantity of peat moss and a much smaller quantity of vermiculite or perlite to ‘lighten’ the mix. Some contain encapsulated, or ‘time-release’ fertilizer. Some more expensive potting soils even contain wetting agents – small granules that hold water and release it only when the soil becomes dry. Most are pH balanced. The old rule of thumb holds true; you will get what you pay for.

When choosing potting soil, the first step is to lift the bag. A good soil will be light, to permit air and moisture to the roots. If the bag is very heavy, it is either black dirt – which you can buy by the yard for about $20- or extremely wet. Very wet soil has been stored outside in the rain and snow, perhaps for years.

Buy potting soil according to your plant’s needs. African Violets like good, rich, black soil. Cacti and succulents prefer lighter soil, almost 100% peat with a little perlite. Years ago, there was only one choice, but in today’s market you can buy soils for almost every type of plant, from bonsai to azaleas, and all are pH balanced.If you have a composter, you can make your own potting soil. Blend finished compost with sharp sand and vermiculite, or perlite, to the plant’s requirements. More sand and perlite makes a lighter soil for succulents like aloe, aralia, agave, euphorbias, stonecrops and cacti. More compost makes the richer soil begonias, spider plants and philodendron thrive in. Do use finished compost; that is, completely decomposed matter, which will look and feel (and smell) very lightweight, crumbly, dark, and almost odorless. The advantage of using your own compost is that it contains microorganisms – something lacking in commercial potting soil, which is usually terilized to prevent the spread of fungal diseases. However, if you are starting garden, flower or house plant seeds, use either a pasteurized, commercial seed-starting mix, or sterilize your own compost in the microwave, in shallow glass pans. Cook a one-inch layer of very damp compost for ten minutes on high, and immediately insert a thermometer to verify the internal temperature of the soil is at least 140 degrees. If it isn’t, repeat the procedure, adding enough moisture to prevent the compost from catching fire.

You can also use compost to make ‘tea’, but not for human consumption! Fill a nylon stocking with compost and drop it in a bucket of clean, warm water. After it has set (in the sun) for a couple of hours and the water is pale brown, remove the stocking and use the fluid to water your prized house plants. The wet compost can then go in the garden as a soil amendment.