When should I top my Bubble gum?

I have 10 Bubble gum seedlings.
There about 5"-6". 3-4 weeks old.
they all have about 3-5 nodes.
i want to top them all since im growing indoors, when should I?

also i have 2 Purple Hardball clones about 10" and have 7 nodes. I'm thinking about topping them too, should I?nd when?

NOW!
you should have done it a week ago a reckon, i top at 3 weeks and veg till theyre 5weeks (2weeks after topping) and then switch to flowering

Okay thanks.
I'm about to top the hardball tonite and the bubblegum soon. so i just top the very top node, the newest one?

no... you top above the second 'true' or 'real' node... the first one with the 3 bladed leaves doesnt count, so the one after that is the first true node.