By Janeen Feiger, Former Nursery Assistant
Here in the Garden nursery, we are frequently asked what kind of potting soils we like to use for our plants. This is not an easy question to answer since there are many factorsthe water holding capacity, aeration, pH, potential shrinkage and morethat have to be taken into consideration. Following are some of the components we use in the nursery with an indication of what they contribute to the mixture. You'll also find recipes for two of our most useful mixes. Please keep in mind that these mixes are what we have found work best for our uses. You may need to adjust the proportions for your particular environments and plants.
The following mixes are those we use most frequently; other, more specific mixes are made based on needs of individual plants. Always determine the needs of the plant you're potting and use the components listed above to adjust the basic mixes, or create new mixes to provide an ideal environment for your plant.
Soil sanitation is essential. Media components must be free of pathogens, weed seeds and insects. Store your components and mixes off the ground so that they are protected from surface water. To protect them from wind, cover whenever they are not being used. Also, never use containers or scoops for new soil without sterilizing them first. It is inadvisable to keep soil components in storage for long periods of time. They or their bags could break down or deteriorate.
I hope this information answers some of your questions. Please remember that there is no single correct mix. There are many options available. With a little experimenting you'll be able to find what works best for you.