Topping New Clones question

I have 3 clones that pretty much all look the same as the photo below. They are three weeks old today. This strain has a tendency to grow tall. I want to keep the plants as small as possible so I would like top them a couple of times as they grow. The question is, When is it safe to start topping them? Are they old enough yet?

i would say right now if you see the 2 leaves are starting to develope under the top

3rd week is frind i top my plants on te 3rd week and they look great!

they look like it. i try to leave 4 good shoots or nodes. then as these four grow i spread them apart to make 4 tops.

yeap they look like its time to cut dont they fdd?

Thanks for the advice!!