What do I do when the plant turns brown? Am I suppose to clip the leaves off?
As long as there are only a few brown leaves, yes clip them off. But, if you are getting many brown leaves, this could be a sign of something stressing the plant. Most often with houseplants, it is either an overwatering or underwatering issue that cause brown and yellow leaves. These articles might be useful for you:
https://www.gardeningknowhow.com/houseplants/hpgen/how-to-water-a-plant.htm
https://www.gardeningknowhow.com/plant-problems/environmental/under-watering.htm
https://www.gardeningknowhow.com/plant-problems/environmental/signs-of-plants-affected-by-too-much-water.htm
What are the ratios for the peroxide homemade solution used for treating white powdery mildew?
Straight 3% peroxide can be diluted 1 to 1 with water (1 part peroxide to 1 part water). In addition, a weekly spray of milk at a concentration of 1 part milk to 9 parts water may significantly reduce the severity of powdery mildew infections.
The leaves keep dropping. I've had it about 2 weeks. It had so much water on it when I bought it that I haven't watered it since. What can I do to stop the leaf dropping?
It may have root rot from being overwatered by the people you bought it from. This article will help: https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm
My plants are all dying. Do you have any tips? The leaves are either drying out and turning brown, mildewing, or falling off.
There are numerous things that can cause this to happen. However, without knowing whether these plants are container grown or planted in the ground, it's difficult to pinpoint an exact cause.
My plant just started to lean. I don't know why. Can you tell me what's going on?
I am going to assume that this is an indoor houseplant. If it is, it is leaning towards its light source. If you give it a quarter turn once a week, this will stop its leaning.
I agree with heather. I turn my plants often, it keeps them full and healthy.
Should I trim the dry, brown ends off of my plant leaves?
Yes, you can trim off the brown edges on the plant. You don't need to for the health of the plant, but if they are making the plant look raggedy, then it will not hurt to do so.
When first planted, it was outdoors. Prior to cold weather I repotted the plant and put it inside. It was doing beautifully. . . I had to prune back and now all the lower leaves are gone. There is only green on the upper part and most of what used to be vibrant is gone? I did give it food every two weeks as it called for.