I have a zucchini plant and the plant is thriving. However, the stem seems to be cracking. I was wondering what is causing this. Any advice? Thanks.
Animal or vine borer damage is likely the cause. If it is vine borer, it probably would not look as healthy as it does, but it does not hurt to check for it. This article will help with that:
If you do not find any pests, you can cover the cracked part of the stem with a mound of dirt. The plant will develop more roots there and will help the plant survive better if the damage continues. The cracks should not hurt the plant as long as they are legthwise down teh stem. If they go crosswise though, this will cause problems.