Zucchini Leaves Become Split
The leaves of my zucchini look as if someone using a fine blade made a slit in the leaf. It's not clear to the edges but totally within the leaf itself. It is centered within the leaf and does not cross the ribs.
Certified GKH Gardening Expert
The following article should be of some help to you: https://www.gardeningknowhow.com/edible/vegetables/zucchini/solutions-for-common-problems-growing-zucchini.htm