I'm in Zone 4, so I'll bring in my grass for the winter. Do I cut it back when I bring it in or in the late winter?
If you're bringing it indoors, then you can cut it back and place it in a somewhat darkened area to overwinter, watering only when extremely dry. Keep in mind that overwintering this grass doesn't always work and although it's labeled perennial, it is actually considered a tender perennial, meaning it will not survive outside its growing zone (cold temps) and is often treated more like an annual in these areas.
I want to move a purple fountain grass. I am in Zone 3. I know to prune in spring, but is it best to move it now or in spring? And if spring, when? Like when new growth begins?
I would transplant them in spring just as new growth appears.
I would like to know if you should prune purple fountain grass back or if you just need to get rid of the spent blooms, and how you go about performing this task.
This article will help: https://www.gardeningknowhow.com/ornamental/foliage/fountain-grass/fountain-grass-pruning.htm
I have 4 plants that I cut back last fall. They are not showing any new growth at this time. Is it just too early? I have other grasses that have really grown. They sit in full sun.
Most likely, it should have come back from now, but I would let have another week or two. This article will help with determining if it is still alive:
https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm
I planted some purple fountain grass last year and it grew tons and thrived. It is now the beginning of May and I still don't see signs of it coming back. I did cut it down early spring. When should I expect it to begin growing back or assume it is not coming back?
They typically emerge in late spring to early summer, though with the unusal weather, the fountain grass may simply be slow to start. I would give it a little more time. Since you already cut away dead growth, this should help encourage new growth. Here is an article to help you determine if it is dead or just on a slow start: https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm
I have 3 very beautiful large full fountain grass plants. It rained very heavy last night and this morning. Now it looks as if someone or something jumped in the middle of the plant! Will they sit themselves back up? Has this damaged the plant? What should I do, if anything? They were so beautiful! They are planted in my beach area around the pool.
They should come back out just fine. This is normal when plants get pounded with lots of rain. Allow the plants to dry out, especially the foliage, and they should begin to stand back up on their own. If for some reason they don't straighten back up, you can trim the foliage back some.
Does the purple fountain grass require more sun or shade? Also, is it an annual plant? If it is perennial, should I plant it in the ground?
In your area, it can be grown as a perennial and planted in the ground. They enjoy lots of sun. Here is more information: https://www.gardeningknowhow.com/ornamental/foliage/purple-fountain-grass/grow-purple-fountain-grass.htm