Hibiscus leaves are yellowing.
There are several reasons for yellowing leaves, stress being one. This article will help you: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm
I get lots of flowers; however, they close and fall within a day or two. Is that normal?
Yes, this is normal. Hibiscus blooms only last one or two days and fade.
Does the plant need full sun? I bought a plant that is supposed to be kept in the ground over the winter. I'm in Zone 5-6 on Long Island, NY. Do you have any suggestions?
Hardy hibiscus does do best in full sun, but it can be planted in part sun. The blooms will not be as prolific, but it will still be fine.
I am in charge of landscaping at my condo, which has a large brick plaza. We have many large pots with tree form hibiscus and potato vines. The hibiscus in one row of pots are struggling. . .the leaves are small and some are yellow and shedding. The others seem to be thriving. They are watered daily. Any ideas?
How often are they fertilized? If they are not fertilized at least once a month, this is most likely the issue. The other issue may be a pest problem. Check the plants closely as some pests can be small. This article may help: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm
I have a red hibiscus which stopped flowering. It's not making buds. The plant is in a container and looks very healthy. Just no flowers. Any ideas what I should do?
It may not be getting enough sunlight. Make sure the plant is getting at least 6 hours of sunlight a day. If this does not seem to be the problem, check the fertilizer you are giving it. It may need more phosphorus. A fertilizer that is high in nitrogen will encourage leaves to grow but will discourage blossoms.
I live in southwest Virginia and have managed to keep 4 hibiscus plants alive outside for 3 years. I just mulch them heavily and cut off the dead branches to about a foot from the ground each winter and new growth comes back in the spring. I've never pruned them because I don't know how. This summer they grew about 5' tall and are very stalky and leggy instead of looking bushy. They didn't bloom until August. How can I keep this from happening next year?
It sounds like they are not getting enough light. Is it possible the light conditions changed? Perhaps a tree near by has grown taller over the past few years that is blocking the sun, or a new building has gone up? Let us know if this might be the case.
We have two lovely hibiscus plants in the garden and recently bought another one, which is in a pot and we hope to transplant to the garden next year. We really do not know how to look after them. The two in the garden are about 6 ft tall and flower beautifully every year. How do we go about pruning, etc. ? Any advice would be gratefully received.
Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/tips-for-pruning-hibiscus-plants-when-to-prune-hibiscus.htm