When is best time to transplant Crocus bulbs?

When is the best time to transplant Crocus bulbs? And what is the best technique?

Crocuses growing in one part of my garden don't get as much light as in another area. Some of them open partly for a short part of the day, and some of them aren't yet opening at all, but in another area they open fully for longer when the sun comes out. I don't want to move them right now while they are all flowering, and wondered if they are easier to move when the roots go back into the bulb? As they are growing with other plants, I don't want to disturb the pots any more than I have to to transplant the Crocuses elsewhere. How deep will the bulbs have gone, and how far down do I have to dig to get them out without damaging them?

I just took some photographs at 1.30pm, having taken some of the same Crocuses at 12.30pm, and noticed that they have opened more even in the shadier area of the garden. I will probably still move some of them to a sunnier spot when they are dormant if it isn't too difficult. If it is difficult, I will maybe just leave them where they are.

At 1.50pm I just noticed that they are all open a lot more, and seem to be in the process of opening more. My garden thermometer reads 12.5 degrees Celsius.

Photos taken at 1.30pm, of Crocuses in shadier area of garden.

 

Best moved when dormant, probably any time after the leaves have disappeared.
They are fairly cheap so I would just buy a few more.

 

I would wait until the leaves die down, so summer. They could be quite deep. You will probably have to disturb the other plants.
If mine I would tip the whole lot out when dormant, salvage the crocus bulbs, replant everything else and water well and stand in the shade until the other plants show new growth.