The lawn beneath my rose of sharon has died. Not even weeds are growing beneath it. What could be the cause? Will this spread to the rest of the lawn? Should I leave it and mulch or do I have to do something?
Try a thick spray of nematodes. Water them in well, then apply a horse, turkey and molasses compost. Water well and watch it come to life.
Depending on the age and size of your rose of Sharon, the grass underneath probably has too much shade and not enough nutrients to grow correctly. In my opinion, I would lay sections of newspaper over the area to be mulched, overlapping, and mulch 4-6''. The newspapers will smother weeds and the rest of the grass, and it is biodegradable.
How can I propagate rose of Sharon?
This link is to a wonderful article on woody propagation by NC State: http://www.ces.ncsu.edu/hil/hil-8702.html
I have had a rose of Sharon planted for two and a half years that still has no blooms.
It might be the age of the plant, or one of several environmental factors. This article should help: (and yes, it's about hydrangeas, but this goes for althea as well!) https://www.gardeningknowhow.com/edible/fruits/lemons/learn-about-fertilizer-for-a-lemon-tree.htm
I have a rose of sharon planted for 2 years, started from a seed. I noticed a week ago the leaves are starting to harden and slightly curl on one side of the plant. The plant is very healthy looking, vibrant green and has not flowered. It is planted in an area that has at least 6 hours of sun. Not sure of the gardening zone.
Most plants grown from seed take longer to bloom than those propagated by other methods. Give your althea at least 3 more years before getting alarmed about lack of blooms. Since your plant is getting 6 hours of sun, that should be plenty. I think your thickening of leaves is a type of virus. I suggest that you take fresh samples to your local agricultural extension office for identification and recommendations. Althea are sturdy, hardy plants and thrive in spite of some difficulties.
Did you have a hard frost last winter that injured the plant? This could be the cause of your problem. If it does not flower this year I would suggest getting a new plant or taking a few cuttings off the current one to propagate it.
I have small black ants inside my flowers. Do the damage the flowers.
It is likely that the ants are either attracted to the pollen inside the flowers or your rose of Sharon may have aphids, which secrete a sweet substance (called honeydew) in which the ants are quite fond of. I would first inspect the plant for signs of aphids (be sure to check backs of leaves) and treat the plant with Neem oil spray. This will get rid of the aphids, which in turn will get rid of the ants. Here is more info: https://www.gardeningknowhow.com/plant-problems/pests/homemade-aphid-control-a-natural-way-to-kill-aphids.htm
https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm
If aphids are not a problem, then here are more tips for getting rid of the ants: https://www.gardeningknowhow.com/plant-problems/pests/keeping-ants-of-flowering-vines-vegetables-and-flowers.htm
Ants will not hurt your rose of Sharon plant. They are actually protective . They eat the bad bugs that can harm your rose of sharon. They do not eat the plant. I welcome ants on my plants cause they like to eat the aphids that attack many different plants.
I planted a rose of sharon last summer when it was in bloom, and now it looks like it's dead. Will it bloom again in the spring? I live in Buffalo, New York.
It should be fine. Right now the plant is dormant and pruning will help improve its appearance. If you wait till late winter/early spring just prior to bud formation, pruning will help encourage new growth. These articles will also help: https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/pruning-rose-of-sharon.htm, https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/rose-of-sharon-bush.htm
I have an old rose of sharon. Every late fall I prune all the new growth off so it does not get huge. After I prune the new growth off, it stands about 7 ft tall. The so called knuckles left from pruning it are huge and some break off. I don't want to ruin the bush. Would it be OK if I cut those so called knuckles off now this year and would the bush still grow for me this year from the heavy branches that are left?
Rose of sharon responds well to aggressive pruning. You can take those knuckles off and the plant will be fine and will fill in well from the branches that remain.