I've posted four photos at the site below (let me know if the link doesn't work).
The first two are Bell pepper plants that have a yellow-lime green discolouration on the outer part of the leaf. The third pic is the cucumber that has some white spots and the celery in the fourth pic also has some white spots (powdery mildew?). This is my first time growing these plants. Just curious if these are normal or cause for concern.
I've used a little potato dust on the pepper (and tomatoes in the same greenhouse) cause it has been humid. I used a baking soda/water solution on the celery and cucumber.
..