Spiderwort carries the quiet mystery of a plant that refuses classification. This hybrid between the common spiderwort and Ohio spiderwort confounded even trained botanists for generations, and many plants still sold under Tradescantia virginiana are, in fact, this more vigorous crossbreed. Its strap-like leaves reach 12 to 18 inches, and the pink blooms open each morning, closing if afternoon sun finds them, lingering longer on cool and overcast days.

When summer heat finally overwhelms the foliage and the whole planting looks spent and sodden, that is precisely the right moment to cut it hard to the ground. New growth follows reliably, and a secondary flush of bloom can carry on into fall. Bees find the spidery-haired stamens irresistible. Hardy from zone 4 to 9, it tolerates wet soil where many perennials would rot, making it useful at pond margins and in low spots where the drainage is never quite right.