OnMySill

Tuberous Begonia / Begonia Tuberhybrida

Begonia × tuberhybrida

description

Tuberous Begonia is a shade-friendly tuberous begonia grown for large colourful flowers.

benefits

  • Flowering
  • Suitable for containers

warnings

  • Toxic to cats
  • Toxic to dogs

How to care for Tuberous Begonia

sunlight

Tuberous begonias descend from woodland-edge plants that receive bright, filtered light rather than harsh all-day sun. Give yours a bright spot indoors or dappled shade outside to support strong growth and flowering.

Bright indirect light or gentle morning sun

Place it near an east-facing window, or a little back from a bright south- or west-facing window behind a sheer curtain. A few hours of cool morning sun is usually fine, but hot midday or afternoon sun can scorch leaves and fade flowers.

If the leaves bleach, crisp at the edges, or flowers fade quickly, move the pot out of direct sun. Sparse growth and few blooms usually mean it needs brighter filtered light.

watering

Keep the compost lightly and evenly moist while it is growing, but never soggy. Tuberous begonias rot easily if the tuber stays wet.

Active growth and flowering

Water thoroughly about every 4-7 days as a starting point, more often in warm weather or a small pot. Check first: the top 1-2 cm of compost should feel dry and the pot should feel lighter. Let excess water drain away.

Water the soil around the plant, not into the crown or over the flowers, to help prevent rot and spotting.

After flowering and during dormancy

When growth yellows and dies back, gradually stop watering. Keep the dormant tuber dry until new shoots appear in spring. A begonia that stays leafy in low light needs much less water, often roughly every 10-14 days, only after the compost has dried further down.

Light, warmth, humidity, pot size, pot material and compost mix all change how quickly it dries, so use the soil check rather than a fixed calendar.

Do not leave the pot standing in water: constantly wet compost can quickly rot the tuber and roots.

humidity

Preferred humidity

50-60%

Tuberous begonias descend from plants that grow in humid, sheltered mountain forests. They are comfortable in most homes at 40-60% relative humidity, provided the air is fresh and not stuffy.

Dry heated air can cause crispy leaf edges, limp leaves, and flower buds that dry up or drop.

In dry rooms

Keep above 40%

Use a small humidifier nearby or group plants together, especially when indoor heating is running. Keep good space between pots and avoid misting the flowers or foliage, as lingering moisture can encourage rot and fungal disease.

temperature

Growing season

18-24°C (65-75°F)

Dormant tubers

Keep above 10°C (50°F)

Its parent species come from cool, humid Andean habitats, so tuberous begonia flowers best in mild, steady warmth. Keep it away from hot radiators and stuffy rooms, which can shorten the bloom display.

Place it in a bright, sheltered spot and move it away from windows if nights turn chilly.
Cold drafts and sudden temperature swings can cause buds and flowers to drop.

nutrition

March - August

Feed every 2 weeks while new leaves and flowers are forming, using a balanced liquid fertilizer at about half strength. A fertilizer for flowering plants is also suitable once buds appear. Apply it to already moist compost, and stop when growth slows and the foliage begins to yellow for dormancy.

Phosphorus

Phosphorus supports root growth and flower bud development. A balanced feed supplies enough without pushing soft, leafy growth.

Potassium

Potassium helps support sturdy growth and abundant flowers, especially on large-flowered cultivars. A flowering-plant fertilizer can provide a little extra during blooming.

Feed lightly on moist soil: pale new growth may need feeding, but brown leaf edges or a white crust on the compost can mean fertilizer salts are building up.

soil

Light, humus-rich and well-draining soil

Tuberous begonia needs an airy mix that holds some moisture without staying soggy, helping its fleshy roots and tuber avoid rot. Use peat-free potting mix blended with perlite and a little fine bark or compost.

pH 5,5 - 6,5

This is slightly acidic soil, which suits begonia roots well. Most fresh houseplant or container compost is suitable; avoid adding lime or using strongly alkaline garden soil.

Use a pot with drainage holes, and never let the tuber sit in water collected in a saucer.