If you are interested in gardening (why else are you here?) and the science behind gardening, The Garden Professors is exactly what you want. They – a group of horticulture professors from several states – post frequent and highly interesting articles. This past week has covered every thing from possible hazards of compost tea to the LD50 of coffee to a review of a classic organic gardening book. Every Friday there is a puzzle – usually on what went wrong with a plant. If you’re looking for a challenge, try these out.