I see very little damage to your plants. The bean leaf has been nibbled but the damage looks old. The main problem is your container size. Your squash and beans are large enough to transplant into much bigger containers. The leaves which are going yellow on the squash are the seed leaves which drop off eventually anyway but the plants have started to exhaust the nutrients in the mix in those little containers and need to be moved on into their final planting positions. Do you know what sort of squash they are? Are they a vining type or bush type? A single bush squash needs a container about the size of a household bucket. Also are there drainage holes in the containers?

This forum is very slow. If you want more advice on growing veggies in containers you could try the Container Forum or the Vegetable Gardening Forum.

I think they need fertilizer. 6-6-6 or 10-10-10. Just a small amount. Like about a teaspoon full per plant. Spread it around equally if you can and water it in. How much sun do they get? Veggies need at least 1/2 day of full sun.

Their greatest need is far bigger containers, no amount of fertiliser will recompense for being in too small a pot.

And they need a lot more than half day sun - both beans and squash are full sun plants - 8+ hours daily.

I agree with floral on container size - squash need a minimum of a 24" diameter container or one that holds 15-30 gallons. And that's for an individual plant, not 4!!

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