begonia rex escargot

Cause

Begonia rex 'Escargot' develops rotting stems and crown at the base of the rhizomatous foliage when the compost is kept too wet or the surrounding air is excessively humid and stagnant, because the soft Begonia rex rhizome cannot tolerate waterlogged compost or saturated still air even though the species comes from tropical rain forests of Assam.

Solutions

• If all the stems of the Begonia rex 'Escargot' are affected, throw the plant away because the rot has spread through the whole crown and cannot be saved.
• Otherwise remove the affected stems at the base with a clean cut and dust the compost surface with a fungicide powder to stop the rot spreading into the healthy Begonia rex rhizome beneath the 'Escargot' leaves.
• Allow the compost to dry out and only resume watering as in ideal conditions, keeping the surface of the compost dry between waterings and never leaving the pot standing in water around the Begonia rex 'Escargot'.

Cause

Dry indoor air around Begonia rex 'Escargot' encourages an infestation of red spider mites that take hold on the foliage and along the stems of the plant, leaving fine white webs once the pest population is established on the soft, thin-leaved Begonia rex cultivar grown for its spiraling leaf colours and textures.

Solutions

• Spray the Begonia rex 'Escargot' with liquid derris and repeat the treatment a few days later if necessary to suppress the red spider mites on the leaves and stems.
• Provide a more humid atmosphere around the plant by standing the pot on a tray of wet pebbles or surrounding it with moist peat so the dry air that drives red spider mites is no longer present around the 'Escargot' foliage.
• Move the Begonia rex 'Escargot' to a cooler room if it has been kept in hot dry air, then raise humidity so red spider mites cannot re-establish on the spiraled leaves.

Cause

Begonia rex (the parent species of the 'Escargot' cultivar) develops fluffy grey mould on the leaves and stems when botrytis fungal disease is encouraged by excessive watering and humidity around the soft, moisture-loving rhizomatous foliage that the cultivar inherits from Begonia rex in the tropical rain forests of Assam.

Solutions

• Spray the plant with benomyl to suppress the botrytis fungal infection on the leaves and stems of the Begonia rex 'Escargot' foliage.
• Allow the compost to dry out and then resume watering as in ideal conditions, keeping the surface of the compost dry between waterings and never leaving the pot standing in water.
• Move the Begonia rex 'Escargot' to a more airy spot with better ventilation so the humid air around the spiraled foliage is no longer stagnant and the grey mould cannot spread across the cultivar's leaves.

Cause

Begonia rex 'Escargot' drops its leaves in winter when the surrounding air temperature falls below the painted-leaf begonia's tolerance, because the Begonia rex species originated in the tropical rain forests of Assam where winter temperatures stay around 60F/16C and a cool, under-heated room in a temperate home can push the soft rhizomatous foliage below its minimum.

Solutions

• Move the Begonia rex 'Escargot' to a warmer room where the minimum temperature is held at 55F/13C or just above through the winter months so cold does not trigger leaf abscission on the spiraled foliage.
• Keep the compost just moist in winter, watering only every 7 to 10 days so cold damp roots do not add to the cold-stress that is causing the Begonia rex 'Escargot' leaves to fall.
• Place the plant in bright light but out of direct sun during the recovery period so the remaining Begonia rex 'Escargot' foliage can support the plant until new leaves emerge in spring.