When is the best time to begin growing seedlings indoors in Southern Ontario?
You should begin by determining within which plant hardiness zone you reside. Plant hardiness zone charts are available from Agriculture Canada at http://sis.agr.gc.ca/cansis/nsdb/climate/hardiness/intro.html . The boundaries of the zones were adjusted in 2000, defining them more accurately and including local microclimates. The Canadian plant hardiness zone system is not the same as the one used in the US, so recommendations in gardening books published in the US should be treated with care until you familiarize yourself with the differences between the two systems. Gardening books from the US and UK are generally intended for gardens in a warmer climate, which may leave you with a garden full of dead plants if you follow their advice verbatim. There are several books on the market that specifically address the needs of Ontario gardeners. If you live near the boundary of a hardiness zone, you should avoid planting anything that is also at the limit of its growing range. A hard winter
