When you are ready to mix ingredients for your container garden, be sure the soil is damp and workable. To determine this, take a handful, squeeze it and allow it to drop. If water comes out, it is too wet; if it breaks apart, it is too dry. But if the lump of soil retains its shape or cracks just a little when it is dropped, it is in good condition to work into your gardening pots.
Be certain your garden containers are clean when you start. Soak used or new clay gardening pots overnight so they will not draw moisture from the soil after planting. This is a very important step when you are beginning your plants life. If the pot draws off the moisture the new plant will be deprived. Clean dirty clay pots with a stiff brush and hot, soapy water. Clean gardening pots will be much more attractive in your container garden.