I have two indian hawthorn plants. One blooms and one does not. Why is this?
Make sure your Indian Hawthorn is planted in full sun and has good air circulation around the plant.
Pruning should only be done after flowering.
You may want to do a soil test. Excess nitrogen can be the cause of lack of flowering. Over fertilizing with high nitrogen can also cause lots of lush greens and no flowers.
A phosphorous application can help promote flowering. Bone Meal is good organic application.
https://www.gardeningknowhow.com/ornamental/shrubs/indian-hawthorn/growing-indian-hawthorn.htm
Our Indian Hawthorn bushes have gotten way too large for the space they are in. I need to cut them back but all their foliage is on the outside of the plant and I am concerned that if I cut them to where they really need to be they will simply die. All the guides say to prune after flowering but that's in the late spring. Would they put out leaves quickly enough to get them through the summer?
The general advice for pruning most established flowering shrubs is to prune them after they have flowered and to prune up to one third of their current size. Generally speaking, established flowering shrubs can usually recover if you don't prune them too much.
But you don't have to necessarily wait until after the plant has flowered. If you want to prune the Indian Hawthornes now (in the spring), you can safely do that. Just don't get too crazy with the clippers or pruning shears and cut them too far back. Cutting 1/3 of their current size away should be about right.
Of course, once you prune them back, you will not be able to enjoy any flowers and berries this year. However, they should bloom again next year.
A few of my Indian hawthorns are very scrawny looking. They have been doing well for 5 years. I think there is poison ivy or oak intertwined in bush. How do I get rid of the poisonous leaves?
They are not more prone to transplant shock, but any plant can be affected by transplant shock. Plus, the older a plant is, the more prone it becomes to transplant shock. Since you moved them twice in a year, this would make the problem worse. The best thing to do is to increase watering and give them some phosphorous, if you can. A tablespoon of sugar in a gallon of water once a week until they start to recover will also help.
The two largest bushes, approximately five years of growth, have leaves only on the tips of the branches. From what I can tell, they have black spot. I have cleaned the bed of all fallen leaves. Should they be taken out, pruned, or left alone after treatment for the disease?
Here are some links and articles to help you determine if treatment or removal of the shrubs is the best choice.
http://www.clemson.edu/extension/hgic/plants/landscape/shrubs/hgic1078.html
https://www.gardeningknowhow.com/ornamental/shrubs/indian-hawthorn/growing-indian-hawthorn.htm
https://www.gardeningknowhow.com/ornamental/shrubs/indian-hawthorn/indian-hawthorn-pruning.htm
I want to transplant my Indian hawthorn. What is the best time of year to do so?
Indian Hawthorne transplant best in spring.
https://www.gardeningknowhow.com/ornamental/shrubs/indian-hawthorn/growing-indian-hawthorn.htm
Can I replant Indian Hawthorns in January? I was told by a gardener that I had to wait until March. I live in Houston, Texas.
Fall and winter are the best times to transplant shrubs in Texas, so you can transplant yours in January. Gardeners in some regions may need to wait until early spring if the ground is frozen in winter.
How can I successfully transplant very healthy bushes?
Transplanting Hawthorn shrubs should take place in spring and they are happy in any well draining soil, full sun location.
It is best to root prune established shrubs 3 months ahead of time. Root pruning is done by taking a sharp shovel and digging down 8 inches down and in a diameter at least 24 inches around the base of the plant. This cuts off the long roots that won't travel with the plant and encourage small roots to form.