Some the sun just beams on nearly all day, they wilt and look terrible. When the sun goes down some bounce right back up. As a matter of fact all of them were bouncing right back up. Now I have a few that seem to look wilted even after the sun goes down. Some, only a small percentage have some yellow leaves, which I thought meant to much water. But I know I haven't been over watering, or at least I don't feel that I have.

What are other causes of yellow leaves?

My other question is, I built a 22in X 20in and 9 inches deep raised bed. I packed the soil really well and filled it almost to the top. I wet it, what I thought really well. However, after letting it sit for a bit I chose a section and dug down the side to see how deep the water had went. It had only soaked through about 4 inches, and that's with 2 gallons of water.

I tested a four o clock in a milk jug, the roots grow fast. I had a plant almost a foot high and the roots had already made their way to the bottom of the jug and had begun to form a circle. I guess cause they had nowhere to go.

What am I doing wrong? Is that to much water or not enough for that size of a raised bed 22inches X 20inches (9inches deep)? It's a lot of soil. Wouldn't the roots already be way much further down than 4 inches?

Last question, for someone who isn't good at how much water to provide, would you recommend a soil moisture meter, and do they work?

Thanks so much.

To much acid in the soil can cause a plants leaves to turn yellow. If this is the case taking some epsom salt and put it around the base of the plant will help that part. No the epsom salt will not hurt the plant if thats not the case.

As far as your raised bed 2 gallons of water can be enough or not enough. It really depends, for one any kind of plant in soil that has completely dried out may take more water than that. When a plant completely dries out the best way to water is by a slow long drip. If you just dumped the 2 gallons of water on the area it may just not of had time to soak in. If an area is wet or has been watered consistently and the ground is not completely dried out it will take less water to reach to the bottom. I really hope that made sense.

As far as a soil moisture meter I personally have never used one, I tend to listen to my plants. If they want water they tell me if they wont less they tell me. I dont get to technical when gardening trial and error is my way to go. I try something if it doesnt work I try something else.

Newly planted four o clocks do have shallower roots so if the plant is healthy don't worry about shallow roots.

Remove the yellow leaves, this is probably a lack of water. Do not confuse drought tollerent with no water at all.

Good luck!