Low yields can, at times, be attributed to poor pruning. If you just let a marijuana plant “do it’s thing” it will want to grow into a sort of spindly stick plant with vertical height but no real bushy-ness. You will want a plant that grows OUT as well as UP. And you want to keep it below fence level outdoors/not poking out the top of the greenhouse.
When your plant firsts sprouts it has a set of “seed leaves”. The seed sends out the tap root ad as it grows the actual seed raises out of the ground and the seed husks fall off . The seed leaves are actually the 2 halves of the split seed and there will be 2 tiny single leaflet leaves that first form in the center of the stem.
After the single leaflet leaves are generally 3 leaflet leaves that appear next
Once the 2nd set of leaves appears you will want to “top” the plant. By pruning the top center growth area off this basically stops the plant from the full vertical growth.
This forces the plant to redirect the growth laterally via the branches that grow from the junctions of the lower leaves. It’s important to do this early with auto flowering plants as their growth cycle is so short.
Doing this repeatedly with the lateral branches every other leaf set will cause them to repeat the branching spread.
A few days after “The Haircut” you will see a huge growth spurt as the plant refocuses it’s growing to the junctures below the topping cut as we see here below