Poinsettia (Euphorbia pulcherrima)
The plant does not suffer from a pathogen infection, but rather a physiological disorder called etiolation caused by inadequate environmental conditions. Insufficient sunlight causes the stems to grow excessively long and weak in an attempt to reach light, while the dry heat from the nearby radiator causes the lower leaves to fall. This combination of factors weakens the plant's structure, leaving it with sparse foliage and a lanky appearance.
Move the plant away from the radiator to prevent dry air and excessive heat from continuing to stress the foliage.
Place in a bright room, near a window but protected by a thin curtain from direct sun.
Trim the longest and barest stems a few centimeters above a node to encourage lower branching.
Place the pot on a saucer with pebbles and water, ensuring the bottom of the pot does not touch the water.
Check substrate moisture with your finger before watering to prevent root rot in etiolated stems.
Moderate, twice a week, letting the substrate dry between waterings.
Abundant indirect light; avoid intense direct sun.
Between 15°C and 22°C; avoid sudden changes and direct heat.
Universal mix with good drainage, peat, and perlite.
Balanced liquid fertilizer every 15 days in spring and summer.
