Q.Cucumbers
My cucumbers have been thriving, I’ve kept them watered, they are in larger containers, with Organic compost, and mulched pretty well. They seem healthy, but leaves are turning pale. I have some compost tea made up, I’ll give them a good dose when the sun sets. Any other suggestions you may have for me, I’d appreciate. Thank you. Happy, Healthy Gardening to you all.
The lighter leaves could simply newer leaves forming, or even signs of pests or fungus.
An application of a balanced or natural fertilizer once the plants have blossomed is recommended.
Take caution to not over fertilize. Too much nitrogen will cause burning of the plant or lots of leaves and no fruit.
Here is a link to refresh you on the care requirements.
https://www.gardeningknowhow.com/edible/vegetables/cucumber/cucumbers-in-containers.htm