The link promised to tell me when I should start my vegetable garden—when to sow seeds indoors, and when to sow or transplant outdoors. Just type in my zip code, and I’d have information customized for my area, courtesy of the National Gardening Association. I rarely click on ads, but I’ve found the NGA to be helpful in the past. Besides, I was curious. I have 24 years of records telling me when to plant in my area—how would their site measure up?