Should a rubber tree plant be root bound? What houseplants should be root bound?
It can stay root bound, but will grow faster if not. Here is an article on plants that are happy root bound:
https://www.gardeningknowhow.com/houseplants/hpgen/should-you-repot-your-plant-happy-root-bound-house-plants.htm
All the leaves on my rubber tree plant are falling off. Can I start over by cutting it way down?
If the stems are still healthy, the tree will regrow the leaves, so you do not need to do anything. This article will help: https://www.gardeningknowhow.com/houseplants/rubber-tree/rubber-tree-plant-leaves-falling-off.htm
I received a rubber tree three years ago and it has gone wild. It's tall and the branches lean away from one another; therefore, it is tall and spindly looking. I was wondering if I could cut it back, and it would it bush out?
Yes, you can cut the plant back. This article will help with that: https://www.gardeningknowhow.com/houseplants/rubber-tree/prune-rubber-tree.htm
We had a rubber plant for two years on the front patio then decided we'd like to plant it out back since it was getting so tall. We put it in the middle of four large pine trees to keep it in the shade. It has regular watering. There's four stalks, it has always been outdoors, and is growing straight up, but we'd like it fuller. How do we trim?
Basically, you will want to nip the ends of the branches off. This will force the plant to grow new branches along the existing branches and will result in a fuller tree. This article will help you: https://www.gardeningknowhow.com/houseplants/rubber-tree/prune-rubber-tree.htm
In the office I work in, we have a rubber tree that is outgrowing its pot. It is probably about 6 feet tall. We would like to transplant it, split it up, or something. I have never dealt with one before and do not want to kill the plant. It loves the window we have it in and is very healthy but becoming top heavy.
Here is an article or two that you may find helpful: https://www.gardeningknowhow.com/houseplants/rubber-tree/propagation-rubber-tree-plant.htm
https://www.gardeningknowhow.com/houseplants/rubber-tree/prune-rubber-tree.htm
Half the leaves on the rubber plant have gone brown, thin, soft and droopy. This is a very sentimental plant. I think it may have been exposed to too much sunlight. What is the best remedy?
I would check for root rot as it can cause that: https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm
It could just be straight overwatering. Only water the plant when the soil is dry to the touch. I do not think that sunlight was the issue though.
Have been given a very large rubber plant, which needs to be staked to straighten it up. Can it be planted outside?
They are cold hardy to 30F. If it gets colder than that where you live, you will not be able to plant it outside.
However, you can prune it to keep it smaller. This article will help with that:
https://www.gardeningknowhow.com/houseplants/rubber-tree/prune-rubber-tree.htm