I always grow purple petunias, not because I like them, but because my younger daughter liked them so much when she was small. I think she still favors them, but not with the single-minded exhuberance she exhibited a decade ago. She’s grown now, and she no longer spends summers weeding at my side and sneaking away to read the books in some shady spot. And still I grow purple petunias even though I’m not enamored of most things purple. A garden just doesn’t seems right without them.