Begonias reach 1–2 feet tall and spread 4–6 inches wide, with white flowers all through the heat. They want part sun and consistent moisture—not a plant that shrugs off dry spells, so water regularly and they'll reward you with steady color until frost.

A quart-size plant gives you immediate scale in a bed or as filler among slower growers. Pick these up through June if you need to refresh tired spots mid-season.