My once beautiful potted hibiscus plants on my patio are beginning to look like crap! I have two plants that have done beautifully on my patio this summer in large pots. Now...both plants the leaves are turning yellow and falling off. One of my plants is almost bare the other isn't far behind. I'm not doing anything different from earlier in the summer. They both are in sunny spots and get adequate amounts of water. No over or underwatering. I thought they needed a little fertilizer and I feed both plants with Miracle Grow. Still the leaves continue to turn yellow and are falling off. I've even changed the locations around to no avail. Suggestions...please! Thank you Garden Stew. :'(
It could be spidermites. The reason I gave up on tropical hibiscus (the one you keep in a pot if you don't live in Hawaii). LOL They are very small, you'd need a magnifying glass to spot them. Usually they are more on the backside of the leaf, you will see small white/yellowish spots on the leaves, and the mites are either white or turning brown/red when "adult". They also like to build a fine web. Other than that... if you haven't changed the watering habit, etc...
There are a few things it could be: overwatering, underwatering, pests, requiring a feed, overfeeding, being root bound. :-? Is there any chance of you taking a photograph of it for us as it may help us to ID what is wrong?
I agree with Calin - Spidermites. We have them here BAD this year ... they have decimated an entire Hydrangea hedge!
Check the drainage. as little bit of water logging can be fatal and you can also apply thin layer of mulch on the soil as it acts like an insulator and protects the plant's root getting affected from temperature changes. moderator's note: removed website link, see point 1.1 of usage rules
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. moderator's note: removed website link, see point 1.1 of usage rules