Begonia: Care and Growing Guide

The three types of begonias

The three begonias most commonly grown in US gardens are wax begonia (Begonia semperflorens), tuberous begonia (Begonia × tuberhybrida), and Rex begonia (Begonia rex-cultorum). Each has distinct care needs, sun tolerance, and best use in the garden. Choosing the right type for your conditions is more important than any other care decision.

Most of what is sold at US garden centers in spring is wax begonia. Tuberous begonias are sold separately, often already in bloom, at slightly higher prices. Rex begonias are typically sold in the houseplant section year-round.

Wax begonia care

Wax begonias (Begonia semperflorens) are the most adaptable bedding plant in US horticulture. They flower continuously from May through hard frost with minimal care. They require no deadheading, tolerate heat that wilts most annuals, and grow in conditions ranging from full sun to fairly dense shade.

Sun and leaf color: The bronze-leaf and dark-leaf wax begonias (varieties like ‘Cocktail Series,’ ‘Big Rose with Bronze Leaf,’ and ‘Senator Scarlet’) handle full sun in Zones 4–9 without burning. Green-leaf varieties are better suited for part shade — 3–5 hours of direct sun with afternoon shade in Zones 6 and above.

A 1998 study published in HortScience found that anthocyanin content (the pigment responsible for bronze leaves) correlated directly with UV tolerance. Bronze-leaf begonias have significantly more leaf protection against sun damage than green-leaf types — this is not aesthetic preference, it is measurable physiology.

Planting and spacing:

• Space 8–12 inches apart in the ground; 6 inches apart in containers
• Plant after last frost date — begonias are frost-sensitive
• Pinch growing tips at planting to encourage bushier growth
• Water at soil level, not overhead — wet foliage encourages mildew

Wax begonias grow 6–12 inches tall and wide depending on variety. The ‘Dragon Wing’ series reaches 18–24 inches — larger and more dramatic but still in the wax begonia family.

Tuberous begonia care

Tuberous begonias produce flowers 3–6 inches across in red, orange, yellow, pink, white, and bicolor. They perform best in Zones 4–9 in bright filtered light — morning sun only, no direct afternoon sun in US zones 6 and warmer.

Tuberous begonias are the begonia for spectacular container displays in shaded spots. Their large, camellia-like flowers look artificial in their perfection. They are also demanding — more so than wax begonias — and reward careful watering and good drainage.

Starting tubers in spring:

1. Start tubers indoors 6–8 weeks before last frost
2. Plant hollow-side-up in a shallow tray with moist potting mix, barely covered
3. Keep at 65–70°F until sprouts emerge (typically 2–4 weeks)
4. Move to bright indirect light after sprouting
5. Transplant outdoors after last frost, once nighttime temperatures exceed 50°F

Watering: keep soil consistently moist but never wet. Wilting usually means underwatering; yellowing leaves typically mean overwatering. Either extreme affects flowering.

Critical warning for tuberous begonias: Do not plant where water collects after rain. Root rot kills tuberous begonias quickly. If your spot has drainage issues, plant in raised containers with drainage holes.

Rex begonia care (houseplant)

Rex begonias are grown for their striking foliage rather than flowers. Leaves display intricate patterns in silver, purple, red, bronze, and green — often swirled or banded. They are primarily houseplants in the US, though they work well as shaded patio container plants in summer.

Care indoors:

• Light: bright indirect light, no direct sun. East or north-facing windows work well.
• Watering: water when the top inch of soil dries. Rex begonias are sensitive to overwatering — they rot quickly in wet soil.
• Humidity: prefers 50–60% relative humidity. Group with other plants or set pot on a pebble tray with water to increase local humidity.
• Temperature: 60–75°F year-round. Avoid cold drafts.

Rex begonias do well as houseplants where other species struggle with low light. Our best indoor plants for air quality guide includes other low-light tolerant options for US interiors.

Growing begonias in containers

Begonias are among the most reliable container plants for US gardens. Wax begonias in 6-inch to 12-inch containers bloom all summer with minimal attention. Tuberous begonias in 14-inch containers with partial shade create some of the most spectacular container displays available.

Container basics:

• Use a well-drained potting mix (avoid garden soil, which compacts and holds too much water in pots)
• Choose containers with drainage holes — no exceptions
• For wax begonias, 6-inch pots work fine; for tuberous types, use 12–16 inch containers to accommodate the larger root system
• Feed every 2 weeks with a balanced liquid fertilizer (10-10-10) during the growing season

In hot US summers (Zones 7–9), move tuberous begonia containers to morning-sun-only positions by late June. Direct afternoon sun above 85°F bleaches flowers and causes petal burn that leaves brown-edged blooms.

For container planting strategies in small outdoor spaces, see our container gardening for small spaces guide. Begonias are among the featured plants in our patio ideas for US backyards guide for shade-covered patios and covered porches.

How to overwinter begonias

Wax begonias: Treat as annuals and discard after frost, or dig up plants in fall, pot them, and bring indoors as houseplants. They survive winter on a bright windowsill at 60°F and can be planted back out in spring. This works but requires significant window space.

Tuberous begonias: Tubers overwinter easily. After the first light frost kills the tops:

1. Dig tubers before a hard freeze
2. Shake off soil; cut stems to 2–3 inches
3. Dry tubers in a warm, airy location for 2 weeks
4. Store in dry peat moss or vermiculite at 45–55°F
5. Replant indoors 6–8 weeks before last frost in spring

Tubers stored correctly survive for years and grow larger and more productive each season. A 3-year-old tuberous begonia tuber can be 4–6 inches in diameter and produce 10–15 stems.

Rex begonias: Bring indoors before temperatures drop below 55°F. Keep as a houseplant through winter.

Common begonia problems

Begonias have no serious insect pests in US gardens when grown in appropriate conditions. Most problems are cultural — drainage, sun, and water management account for 90% of begonia failures.

Companion plants for begonias

Wax begonias work well as edging plants beneath taller annuals. Pair them with:

• Coleus: Shade-tolerant, foliage-focused companion that fills similar conditions. Our coleus care guide covers the full range of coleus varieties that pair with begonias in shaded beds.
• Impatiens: Classic companion for part-shade beds; similar scale and similar water needs.
• Ferns: For shaded container combinations, ferns and Rex begonias create layered texture.
• Caladiums: Dramatic foliage companion for shaded summer beds.

For building a complete summer annual bed, our annuals that bloom all summer guide covers full-season bloomers that complement begonias in both sun and shade. For deer-resistant planting options that hold up alongside begonias, the deer resistant flowers guide includes annuals with similar growing requirements.

Wax begonias are mildly deer-resistant due to their slightly fibrous, bitter foliage — deer prefer other plants when begonias are available. This makes them reliable in gardens with moderate deer pressure.