you can by bluebells coming into flower around about now. In the green means when they are in leaf either before or after flowering.
are you going for the english bluebell or the more vigourous spanish bluebell?

Both are nice but the spanish is hybridising with the english one and there is general concern that we may lose the native one.

I have both and am slowly 'containing' the spanish ones.

Please don't buy the Spanish one! The organisation Plant Life have done a survey to discover the extent of hybridisation and it is quite frightening. It is much easier than it used to be to get the true English ones.
I have some Spanish, some English and some hybrids and am trying to steel myself to dump the foreigners, but it is so hard when they are growing well and so pretty!

The other trouble is that the bulbs go so deep after a while it is difficult to dig them up. I too have a mixture of Spanish and English. I may let some English set seed but pull out the Spanish stems when they are ready to pull out. I love the blue colour. Like a lot of attractive plants they have a downside to them.

There was a shrub in my garden, when we moved in and some one had planted bluebells under it. When we had the shrub dug out with a tractor and bucket, I removed a bucket full of the bluebell bulbs and planted up in our wood. That was 7 years ago. I created a little rockery garden and put some large perennials in. Over the years I have removed the bulbs when I could find them. But not finding as many as there are apparent now. they have overtaken the little plot 6' x 5'. and I will have to dig the whole area out. The perennials have been suffocated and non have survived this year.
So please beaware that you're little bluebell garden may not turn out to be what you imagine now.