I didn't see a celery topic, so I started this one. I am trying to grow celery for the first time and know little about it. I bought 4 plants accidentally, thinking I was getting Italian parsley. I know I'm supposed to have square boxes around the stalks. Well, I suppose they could be round, but mine are square. Aside from this, I haven't a clue, so HELP! moderator's note: added a more descriptive title to topic
Celery has very small feet. It needs liberal compost and side dressings of compost as the season progress. On sandy soil I had to water bout every day. I wouldn't start blanching celery till your about sure its the size you want to harvest. Any cardboard box or tube made of brown paper shopping bags that will fit over most of the bottom 3/4 of plant will do. Blanch for two weeks and then harvest. Blanching won't make celery totaly white, but will reduce the green, and make it milder.
We grew celery in upstate NY, and it was a good spring crop for us. It does need a lot of feeding, and watering, but the result is worth it. We put boards on either side of the celery when it was about 18" tall. That blanched it and was easier for us than trying to enclose each individual plant.
In the UK it grows pretty well, but here also you need to make sure it stays well watered and often too!