I live in south Fla. and need to prune my blooming hibiscus. They are beautiful but are too tall. When should I cut them to keep them blooming?
Spring would be the most ideal time for pruning this plant. Here is an article that will help: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/tips-for-pruning-hibiscus-plants-when-to-prune-hibiscus.htm
There are several reasons this can happen. This article explains many of them and will help you decide which is likely for your plant: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm
The Hibicus bush is a tropical plant and does not like the cold. When the temps warm to a low of 60 to 65 at night cut back the top to approx. 24 in high and use a good all perpose fertilizeer. also a little ironite at least once a year will be helpful.
What do I do rid my Hibiscus plant of bugs in the soil and the leaves?
Treat the plant with neem oil. It is effective for ridding many insect pests. You may want to water the soil with a neem oil solution as well, or repot if it's in a container. This article will tell you more about neem oil: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
Why are the leaves on my hibiscus bushes turning brown, which I planted 1 week ago?
This could be attributed to transplant shock, too much sun or cold temps. Most likely it's transplant shock since they were recently planted. This article should help: https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm
I have a hibiscus tree that I thought died due to cold weather but noticed it's showing new growth at the very bottom of stalk. I read where I should cut those shoots and also dead branches at very top where it meets branch. Is this info true, or do I need to cut it all the way down?
This article will help with pruning hibiscus: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/tips-for-pruning-hibiscus-plants-when-to-prune-hibiscus.htm
I have hibiscus that have been cut back and covered with plastic all winter. Is there hope that they will come back? New Bern, NC 28562
You shouldn't cover any plant with plastic, as this will smother the plant and kill it. Only cover plants with something that breathes, such as a blanket or burlap. I would definitely remove the plastic, if you haven't already done so. Generally, in your area hardy hibiscus plants do well outdoors without any type of covering, other than perhaps some mulch. If you have a tropical type, then it needs to be wintered indoors, as it will not survive freezing temps at all. Whether or not the hibiscus come back depends on if they're still alive. This article will help with that determination: https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm
I have a hibiscus tree that has a white substance on it. What can I do?
This is powdery mildew. This article will help:
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm