I have several pots of mums but no flower beds. Can I winter them inside in pots or do they need the sun, and do I water them?
The answer depends on the type of mums you have. If they are the popular florist mums, that are sold by the millions in stores all over the country from late summer through early winter, they are more like annuals, and don't winter over. If they are garden mums, often called hardy mums, they normally die back in the garden, so if you want to overwinter them in the garage, treat them like potted perennials, which involves waiting till they start to die back then cutting the stems to a height of 2 - 3", keeping them cool, dark, and water very little or none, only enough to keep the soil from getting scratchy dry. Or you can try keeping them as a houseplant; cut back by about 1/2, keep in a sunny window, and water enough to keep them slightly damp.
Can chrysanthemums be rooted in water?
They do not root well in water. It is better to root them in soil or sand.
I got a mum from my grandmother's funeral in November. Can I still plant it outside? I live in Michigan, or how do I take care of it indoors? It's very big.
The probability is that you've got a florist mum, as opposed to a garden mum. Florist mums don't generally do well outdoors, as they have shallow root systems, and they also don't generally live a long time. because they are bred to be short-lived flowering plants. However, with proper care, you can keep your plant alive for a month or more. https://www.gardeningknowhow.com/ornamental/flowers/chrysanthemum/growing-chrysanthemum-flowers.htm
If you can keep it going tiil spring, you can try moving it outdoors. This article has more information: https://extension.missouri.edu/p/G6511
I have garden mums which I had bought in pots. Can I save these by putting them inside until spring so they will rebloom again in the fall? What steps do I take to do this?
Mums actually make excellent potted plants. Once the temps in your area begin to drop, bring the plant indoors for overwintering. Keep the plant in a well-lit location, free of drafts, and care for it as you normally would. In the event that something goes awry, which it shouldn't, you can also take cuttings of the plant and root them to ensure a continual supply year after year. Here is more info on that: https://www.gardeningknowhow.com/ornamental/flowers/chrysanthemum/mum-propagation.htm
I purchased mums and kept them in a pot but now I want them in the ground so they will bloom in the spring. When is the best time to plant them?
Mums do not bloom well in the spring. They get maybe 1-2 flowers per plant, if that. You can, however, plant them in the spring and pinch them back hard in late spring/early summer and they will bloom wonderfully in the fall.
They can be treated like high light houseplants until spring. Keep the soil moist and put them in as bright a light as you can find.
How do I prune my mums in the spring so they will bloom in the fall? I have a big beautiful yellow mum that blooms in the summer and fall. It stays big and brown during the winter but I want it to be beautiful again this fall.
If you did not dead head the mum plant before winter, I would do so now or very early this spring. When your mum is done with it's first bloom, cut it back. When the days become shorter this will trigger your mum to bloom again this fall.
It is very hard to determine a set blooming schedule for garden planted hardy mums. It will all depend on temperatures and daylight hours.
I live just a bit north of you, and do need to add a bit of weather protection for my hardy mums.
Here is a link about hardy mum care.
https://www.gardeningknowhow.com/ornamental/flowers/chrysanthemum/growing-chrysanthemum-flowers.htm
I want to start growing mum flowers in my farm. Kindly guide me whether it is possible to grow these in Nagpur area. How many farmers are growing mum crops? What is the ideal season for plantation of mums? From where can I purchase seeds and technical support?
I would do searches for large quantities seeds and plants for farm production in you area.
Contact any local agriculture organizations that may be able to offer assistance in new farming start ups.
https://www.gardeningknowhow.com/ornamental/flowers/chrysanthemum/growing-chrysanthemum-flowers.htm