Clay soil question?

I was unable to dig holes for all of my outdoor seeds. Most of them I placed in root riot starter cubes and placed them in the soil. The soil is high in clay with next to no top soil and no duff layer, I live in the Georgia Piedmont region.

Does anyone have a range of the decrease in yield i should aspect.

FYI..I planted yesterday and the plants will receive 6 hours of direct sunlight.

Wow man, sorry, but it doesn't sound very promising.

Only six hours of direct light, in unamended clay soil....we have the same soil here and I wouldn't ever think about trying to grow straight in it. It just seems to me like the root system determines the size of the plant and your plant won't be readily able to stretch it's roots.