Celery can be frozen for use in cooked dishes. Wash, trim and strip coarse stems from young stalks. Cut in 1-inch pieces or chop.
Blanch in boiling water. Boil for 3 minutes (2 minutes for small chopped pieces). Cool immediately and drain well.
Leave 1/2 inch of headspace.
Page 1 - Vegetable Freezing Guide: Blanching and Packing
Page 2 - Preparation and Blanching Times for Specific Vegetables
Page 3 - Cooking Frozen Vegetables