What makes leaves leaf out in annual seedlings?

Hi.
Growing microgreens and noticing that Pea seedlings don't leaf out very well or early enough.
Tried increasing water, thinking the plant would want to expell that water and leaf out in response, nothing.
Tried germinating them with light, nothing.

Another option is a lack of nutrients, but I don't want to go down that road.
Yet another is light availability. We don't have many artificial lumens on them, like just enough to get them to grow.

Having the same problem with radish.
They tend to grow just fine, they only leaf out at a later stage than I would like.

Thanks,
William

bump!

Thanks for the bump.

I chose to resolve it because I changed pea seeds and apart from being certified and lab-tested for harmful bacteria, the leaves on the pea shoots are leafing out immediately, so problem solved.

The only other one was daikon radish whose leaves need a little longer to leaf out, oh well.

I don't think adding chems, organic or otherwise (which I wouldn't do anyway) would help.

William