The NGA learning library has information about celery (but in this item they assume it will be grown out of doors so adjust the information accordingly). Many people prefer the taste of celery that has been blanched - that is not a cooking term in this instance, but a gardening term - exclude sunlight to make the stalks more tender, less bitter, a better flavor.
http://garden.org/learn/articl...
Here is an off-site link where they suggest using newspaper to blanch the celery...I think Philipwonel had a good idea with the milk carton cut off both top and bottom - much stronger than newspaper.
:http://www.gardeningknowhow.com/edible/vegetables/celery/learn-about-blanching-celery-in-the-garden.htm
