stretching seedlings.

I have 2 grand daddy purp and a blue dream seed in soil and theyare starting to stretch I move the light closer but I was wondering if there's anything I can do like putting more soil on the stem to shorten it

Can I kinda mound soil around the stem?

You can burry them with-in 2" of first leaf.

Burry them right up to the bottom leafs.... I've even plucked the bottom two and buried them deeper.

Sweet. Thanks guys.. I really want to give them the best start.