Last years Celery

I grew a pile of celery last year, and didn't have a decent method for storage, so I had a good lot of them left in a little trench at the end of last year. 

I didn't think they were particularly hardy, so I was surprised this spring to find that a few of them had survived the winter (I live in N Yorks, and had temperatures down to around -20 degrees!) 

Anyway, I now have a couple of pretty healthy plants growing - does anybody know what will happen to them - will they be a good new early crop, or is my only hope to grow them for seed, or should I just cut my losses now and grub them up to give the space to another crop?

Thanks kindly for any advice

Thanks Yorkie, registered a while ago, but haven't used the site in anger as of yet!

Hope to become more of a regular on here!

you could add it to stock and stuff as a way of preserving it