How-to Guide
How to Grow Begonias
The short answer
Set begonias out after the danger of frost is past, in moist, well-drained soil with plenty of organic matter, spaced about 12 inches apart in beds (Clemson Extension). Match the type to the light: bronze-leaf wax begonias handle full sun, green-leaf wax types prefer morning sun with afternoon shade, and tuberous begonias grow best in partial shade.
Wax begonias are fire-and-forget bedding plants. Tuberous begonias give you the big blooms and trailing basket forms — and you can save them: dig the tubers before the first fall frost and store them at 45 to 55°F for next year.
Pick the Right Begonia for the Light
- Wax (fibrous) begonias — compact bedding plants; bronze-leaved varieties perform better in full sun, green-leaved types want morning sun and afternoon shade to prevent sunscald (Clemson Extension).
- Tuberous begonias — big, showy flowers; grow best in partial shade. Trailing types with 12-18 inch stems are made for hanging baskets.
- Either way, hot afternoon sun on green foliage is the most common begonia mistake.
When and How to Plant
Plant outdoors after frost danger has passed. Begonias want moist, well-drained soil enriched with organic matter. Space plants about 12 inches apart in garden beds; closer spacing is fine in containers (Clemson Extension).
Watering Without Scorch or Rot
Avoid watering when hot sun is hitting the foliage — wet leaves in full sun scorch. Water early in the morning, or use drip tape or a soaker hose to keep foliage dry and reduce fungal disease (Clemson Extension). Begonias want steady moisture but never waterlogged soil.
Containers, Window Boxes, and Baskets
Begonias are excellent in window boxes, hanging baskets, and other containers. Trailing tuberous types, with stems 12 to 18 inches long, are the classic shade-basket plant. Container begonias can be spaced tighter than bed plantings for a full look from day one.
Overwintering Tuberous Begonias
- 1Dig before frost — Lift tubers before the first fall frost kills the plant.
- 2Cut back — Cut tops back to within a couple of inches of the tuber and let them cure/dry.
- 3Store cool and dry — Pack tubers in cardboard boxes between layers of vermiculite, peat moss, or wood shavings, and store at 45 to 55°F until spring (Clemson Extension).
✔ Wax begonias are not worth digging — treat them as true annuals and replace them each spring. Tubers are the only part worth storing.
Common Problems
- Botrytis blight, stem rot, powdery mildew, and root rot — almost all traceable to wet foliage, poor drainage, or crowding.
- Mealybugs, spider mites, thrips, and scale; thrips can transmit INSV and TSWV viruses.
- Snails and slugs chew begonias in shady beds — check after rain (Clemson Extension).
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- Clemson University HGIC — Begonia — Plant after frost danger; light needs by type (bronze vs green wax, tuberous part shade); 12-inch spacing; morning/drip watering; hanging basket use; tuber storage at 45-55°F in vermiculite/peat; disease and pest list
- University of Minnesota Extension — Tuberous begonias — Tuberous begonias grow from tubers that go dormant in winter; large bright flowers and trailing habit suit hanging baskets; grow in bright shade with well-drained soil