However, be careful not to use peat or peatlite mixes alone. By themselves, these media tend to become compacted, too lightweight, and hard to wet. You can create your own blend of soil mix by using peat moss, vermiculite or perlite, sterile potting soil or composted soil mix, and coarse builder's sand. In order to determine how much lime may be needed to bring the pH into the 6.0 to 6.8 range, send a sample of the mixture to a soil testing laboratory. Some commercially prepared growing mixtures have an added wetting agent which is a great help when it comes to planting and watering.
Polymers are nontoxic and last for a number of years before breaking down in the environment.
Most soil mixtures become compacted and root-bound over time. It is best to replace containers with fresh soil mix at least once a year or every other season. Most vegetables are grown in a particular season of the year and therefore make excellent container garden plants. Some vegetable varieties have a more compact growth habit, such as Fanfare cucumber and Husky Gold tomato. Look for All-American Selections Winners, many of which are excellent choices for container gardening.