How to grow and care for Polka Dot Begonia Indoors

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Houseplant, Polka Dot Begonia, Begonia maculata

Botanical name: Begonia maculata
Family: Begoniaceae

Polka Dot Begonia also called Trout Begonia, Begonia Wightii or Spotted Begonia is an evergreen shrubby plant which bears large, glossy, olive-green leaves blotched with white dot-like spots and hence the common name. The leaf underside are red colored. This evergreen flowering Begonia may be less spectacular in bloom than other Begonias but has the advantage of keeping its beautiful "Angel Wing" leaves through out the year. It is one of the popular cane-stemmed Begonias. It is easy to grow and propagate. Polka Dot Begonia can reach the height of 6 ft or more if left unpruned. The flowers are large clusters which hang from the stems. Polka Dot Begonia is native to the tropical regions of Brazil.

How to Grow Polka Dot Begonia (Begonia maculata)

Light

Polka Dot Begonia grows best in bright indirect light. Keep it away from direct sunshine as it can lead to scorching of the leaves. Learn how to ensure your plant receives the correct light in this guide on understanding light for houseplants.

Water

Water Polka Dot Begonia thoroughly during the growing season and allow the top 1-2 in. of soil to dry out between waterings. Reduce watering in the cold season to keep the soil slightly moist as growth is minimal. Avoid waterlogging as it can lead in root-rot. Learn more on how to water houseplants.

Temperature

Average warmth with a minimum 15⁰C is ideal for Polka Dot Begonia. Protect the plant from cold draughts.

Humidity

Average room humidity is adequate for Polka Dot Begonia. Where the room temperatures are too high making the air too dry, employ these techniques to raise humidity for the plant.

Feeding

Feed Polka Dot Begonia with a balanced water-soluble fertilizer weekly during the growing period. To promote blooming, apply a phosphorous-rich fertilizer weekly when buds begin to develop. Withhold feeding during the cold season as growth is minimal. Learn more on how to feed houseplants.

Repotting

Repot Polka Dot Begonia at the beginning of the growing season only if the plant has become root-bound or is too large for the pot; the plant prefers to be slightly root-bound. Use a rich free-draining soil and a pot 1 size larger. Ensure the pot has a drainage hole to prevent waterlogging as it can lead to Root-rot Disease. Do not repot a flowering plant as the shock of repotting will cut short the flowering.

Pruning

Pruning Polka Dot Begonia is easy. Remove the dead flowers, yellow and dead leaves to keep the plant neat and tidy. Do not pinch the growing buds. Cut back the bare stems at the beginning of the growing season to rejuvenate growth. The foliage emanating from pruning can be used to propagate new plants. Learn more on how to prune houseplants.

How to Propagate Polka Dot Begonia (Begonia maculata)

Polka Dot Begonia is propagated during the growing season from stem-tip cuttings.

Propagation of Polka Dot Begonia from Stem-tip Cuttings
Take a stem-tip cutting from a healthy Polka Dot Begonia of about 3-5 in. and ensure it bears at least two sets of leaves. Insert it in moist free-draining soil and place in a warm shaded place. Maintain the soil moist through out until new growth emerges. Allow the plant to be well established before transplanting.

Common Problems in Growing Polka Dot Begonia (Begonia maculata)

Yellowing leaves

The leaves of Polka Dot Begonia may yellow due to two reasons. One is too little light; move the plant to a brighter spot. Polka Dot Begonia prefers shade to bright light but away from direct sunlight. Two is too little or too much water; maintain the soil moist at all times but not soggy. Never allow the soil to dry out completely. Learn more on how to water houseplant.

Loss of leaves

There are three reasons for loss of leaves in Polka Dot Begonia. One is too little light; move the plant to a brighter spot. Polka Dot Begonia prefers shade to bright light away from direct sunlight. The second reason is too much heat; the best temperature for Polka Dot Begonia is average room temperature that is a temperature that is comfortable for you is good for this plant. Third is too much water (waterlogging); ensure the soil is free-draining and the pot has a drainage hole.

Flower buds drop

The causes of flower bud drop in Polka Dot Begonia are two. One cause is dry air; raise humidity by setting the pot on a wet pebble tray but do not mist the leaves. The second cause is underwatering; maintain the soil moist at all times and never allow the soil ball to dry out completely.

Brown leaf tips

If the air humidity is too low, Polka Dot Begonia will respond with brown leaf tips. Employ these techniques to raise humidity for Polka Dot Begonia.

Pale, rotting leaves

The reason for pale, rotting leaves in Polka Dot Begonia is waterlogging of the soil. Maintain the soil moist but not soggy. Ensure the soil is free-draining and the pot has a drainage hole to prevent waterlogging.

White powdery spots

This is an indication of Powdery Mildew in Polka Dot Begonia. Isolate the affected plant, cut off diseased leaves and treat appropriately. Avoid damp conditions and low temperatures and improve air circulation.

Brown blotches, turning grey and moldy

This is an indication of Botrytis Disease in Polka Dot Begonia. Isolate the affected plant, cut off diseased parts and treat appropriately. Avoid low light and over damp conditions and improve air circulation.

Plant collapse

There are three reasons for plant collapse in Polka Dot Begonia. One is Stem Rot Disease due to waterlogging. The second reason is Nematodes (Root Knot Eelworm) which are characterized by swollen bumps on roots. The third reason is Vine Weevil which is characterized by tunnels in the rhizomes.

Pests

Common pests in Polka Dot Begonia are Aphids and Red Spider Mites.

Toxicity

All parts of Polka Dot Begonia and especially the roots are considered mildly toxic to pets. If ingested they may cause burning in the mouth and throat, vomiting, diarrhea and abdominal pains.