why do the leaves on my hibiscus plant turn yellow

Hibiscus plants are quick to respond to abrupt environmental changes, such as temperature, fertilizer applications, and soil and air moisture. When days grow shorter and temperatures get cooler, seasonal changes trigger yellowing, dropped leaves, which is a normal occurrence. Hibiscus plants are not drought-tolerant, and they require moist soil to thrive.

Some species, such as swamp hibiscus, can grow in boggy conditions at the waterвs edge, but most varieties must have well-draining soil. In areas with arid summers and infrequent rainfall, such as in Mediterranean climates, hibiscus must be kept watered to maintain consistently moist soil.

If soil is allowed to dry out, leaves react to this drought stress by turning yellow and falling. Yellowing leaves may also indicate fertilizer stress -- either too much or not enough. Dr. Dave Williams, of the University of Alabama Cooperative Extension System, recommends frequent applications of half-strength liquid fertilizer during periods of active growth and once every six weeks in winter.
Stress is the reason why a hibiscus plant turns yellow.

It will eventually fall out of it s branch if not treated properly. I have to agree with everyone else here that spider mite could be one of the reasons why it turned yellow but there are also other this that can be the culprit of the color change.

These can be either, you don t water the plant enough, you water it too much, extreme temperature changes (too hot or cold), or it can also be due to a pesticide that you might have used.

Try to examine what changes brought about the change in color. In your case, since you mentioned that you aren t doing anything during the season, it can be because of spider mites or too much sunlight. removed website link, see point 1. 1 of