Use the right soil mix

Plain garden soil is too heavy and dense for use in container planting. The best soil mix drains well, retains moisture, provides support for the plants and is not so heavy that it could cause a structural problem on a balcony or rooftop. (SEE ROOFTOP GARDENING TOOLBOX).

You may have to experiment with a few different brands until you find the right one. Or buy a basic mix and make some additions. For a good do-it-yourself mix, combine 1 part of packaged potting soil with 2 parts of organic matter (compost, shredded bark, leaf mould, peat moss, cow or sheep manure, etc.)

To improve drainage, sharp builders sand is a good addition. Remember to tailor the soil mix to the plants’ needs. The proportions of the mix can vary container by container, depending upon the plants themselves.