Can I plant crocus bulbs in late November to flower the following spring? I have a sunny south facing garden in North Lancashire England. I intend to plant 100 + in the lawn. I do not use any form of weedkiller in this area.
As long as the ground has not frozen, you can still plant crocuses. The location sounds good.
My crocus plants just came in that I ordered. Can I plant them now and still have time to bloom in the spring? I am new to the gardening world.
As long as the ground has not frozen where you live, you can plant them and they will bloom. If it has, this article will explain how to store them till spring: https://www.gardeningknowhow.com/ornamental/bulbs/bgen/preparing-bulbs-for-winter-how-to-store-bulbs-for-winter.htm
Do crocus flowers need to be trimmed, pruned, or dead-headed?
No, these bulbs are pretty much self cleaning. They need their leaves to store energy for next year, so hold off a bit before cutting them if they are naturalized in your lawn. As for the flowers, you can take them off if you like, but you do not need to. They may go to seed and produce more crocus. In some bulbs, the seeding can take away from the flowers for next year, but crocus are so prolific that it is not a concern for them.
I recieved the plant in February and all of the blossoms are gone now. What do I do next so I can plant them outside? Does something special need to be done before planting them, and when do I plant them?
This article will help you with that:
https://www.gardeningknowhow.com/ornamental/bulbs/bgen/how-to-plant-a-flower-bulb-in-your-garden-after-winter-forcing.htm
When the crocus bloom withers and dies, should I cut it off?
You can take the faded flower, but leave the leaves. They need those to store energy.
About 3 1/2 years ago, I planted crocuses in my yard in 12 x 15 inch rectangles and had a nice display for two years. Then, last year there were just a few blooms. This year, I had many plants, but only two blooms. What must I do?
Either there is a phosphorus deficiency in the soil or the corms are overcrowded. Try giving them a high phosphorus amendment or fertilizer (like bone meal) and dig a few up to see if they are too crowded.
Should the crocus corms be removed from the soil after the flowers have died off and replanted in the fall?
Only in very warm areas do they need to be dug up. Most places do not need to dig them up in the winter to pre-chill them and they actually need cold weather to bloom.