Pumpkin, sunflower, kale, garlic, lettuce, roses, aloe, sedum, cosmos, hollyhock: Only speckles of concrete could be seen under the masses of plants that consumed Aneice Taylor’s Woodacre driveway last weekend. For those who just discovered the (18th annual) In Spirit plant sale by chance, the plants meant added decor to a home or garden. But for about 20 . . .