Can my Dog eats Celery?
Ok in Limited
As part of the leafy greens family, celery has perfect nutritional values. It contains plenty of vitamins (A, E, K, B, C) and has extremely high water content. Since most leafy greens are canine friendly, it is only logical to assume that celery is safe for dogs.
However, that is not the case. In spite of its healthy and highly nutritious values, celery is not recommended for dogs. This is due to the celery’s tough consistency and stringy texture. If dogs toke their time and chewed their foods properly, these factors would not be an issue. Unfortunately since dogs tend to be voracious eaters and do not bother to chew, the celery may pose a dangerous choking hazard if it ends in the windpipe. On the other hand, if the dog swallows it, the strings are likely to curl up and cause intestinal blockage.

Bottom line, considering the possible side effects and the fact that there are far healthier and safer treat options available, it can be concluded that celery is not recommended for dogs.
What should I do if my dog ate Celery?
If your dog ate celery, and if he is not well, observe it for any changes in behavior and if some issues arise, call your vet.