BROKEN STEM!help please

i have this 15 days old plant, it was pretty tall and leaning so i put a toothpick to handle it straight and this morning at 8 i put it outside at the sun, there was a bit of wind and when i came back the stem was broken the plant was leaning on the soil!! so i built a cast please look at the pictures!
is the cast a good idea or should i add more soil so the crack is under the soil? what should i do? u can see the broken stem in one picture.. do i need any specific nutriments?

that plant is stretching bad. bury it till theres about an inch of dirt below the leaves and move your lights closer or its not gonna grow properly. it wont support buds if you dont .

if its still attached it will be fine. next time plant it in a pot, and fill the soil up to the first set of leaves. this lower the risk of the stem breaking, just be super careful when filling soil around the stem!

so how is she doing now?

move the light closer, push it into the soil down farther and do what everyone else sayd