My experience with celery in the “crisper” is that it does not actually stay crisp. It usually does not take long before I try to pull off a stalk of celery and find it to be rubbery. A while back, I heard a tip for how to keep it crisp and I finally tried it out. Wrap the bunch of celery in tin foil. This works! My celery stayed crispy for 2 weeks this way. Definitely try it if you know you will not be using the whole bunch right away.