Gadgets to Help Tend a Garden Collecting pollen with a VegiBee, which helped tomato yields rise 38 percent for Bill Whaley, the tool’s inventor. Tim Parker for The New York TimesPicture a tiny drone that arises from your vegetable garden to shoo away hungry deer. Or maybe a houseplant that, when you’re away, meanders through your rooms like a cat following a sunbeam. Or one that posts a request for water on Twitter. The future is knocking at the door of home gardening. And, if some do-it-yourselfers have their way, there is no aspect of nature that can’t be improved with a rechargeable motor and a sensor or two. ake, for example, the VegiBee. Bill Whaley, a former department store executive living in St. Louis, said he invented the device after a disappointing tomato yield. Mr. Whaley concluded that the problem was pollination, and quickly set out to improve on the bees, which were clearly remiss. Looking a little like an electric toothbrush, the VegiBee’s wand is held close to a flow