I moved my hibiscus bush outside when the weather was warm enough, but now it looks sad and some of the leaves are yellow and have spots on them. I checked for insects and found nothing. I sprayed it with insecticide a week before pruning and it did great until I moved it outside. What is wrong?
Your Hibiscus can safely go outdoors when the temperatures warm. 60 degrees is ideal.
Your plant needs an adjustment time to the brighter outdoor sunlight. Gradually place it into the bright sunlight.
Watering will need to be adjusted when the plant move from indoor to outdoors.
Yellowing leaves can indicate a watering issue; too much or too little.
Insects are common on Hibiscus. Spots on leaves can indicate an infestation.
Neem Oil is a good treatment. Neem Oil is organic and safe for people, pets and bees.
Your plant may also need fertilizer.
Here are some links with more information.