When to top seedlings to become mothers?

Hoping for a little advice from some more experienced than I...

I am growing 8 white russian and 8 indian haze (Joey Weed) from seed. My intentions are to come out with 1 mother plant of each strain.

I plan to top these plants as to bush them out, and root the tops to reveal the plants sex. So I know which plants to cull out. Male. You know.

My plants are now about 6 inches tall (+- 2in) and about 6 weeks old (+- 1 wk). 4-5 leaf sets (is that what they are called?) going up the stalk.

My question is... When should I make my first cut off the top as to make smaller bushier plants? I don't want to do it to early, however, I have heard that early is key. Anymore suggestions would be great as well. How many times should I top, other training techniques, anything I should watch for?

Growing under a 400 watt MH with cooltube in a 70 cube ft room. Exhausted and air cooled w 440 cfm fan. Active intake with 125 cfm fan. Both fans on full speed. h - 7 ft, w - 5 ft, d - 2 ft closet. 16 inch osci circ fan posted mid heighth. Light hung 12-16 inches above plants. Grown in soiless mix, currently 6 inch square pots, fed with Canna Substra and much love.

I am growing these mother plants to be moved to an armoire cab flourescent setup where mothers will be maintained, clones rooted, and veg grown to height, cab dimensions: (6 ft tall, 3 ft wide, 2 ft deep). Veg will then be moved to flower in my closet where they are now. In the closet they will be flowered under the same setup, uprgraded to 600 watt HP sodium. Might drop in a few large compact flour on the outer borders where they will not be blocking light from the HP Sodium.

After I move my two mothers to the cab, I hope to flower any other females from my 16 plants. Then when the plants from seed are harvested, I already have my line of clones to be moved in and start my perpetual thing.

I have grown 3-4 yrs outdoor. This is my first full indoor. A different game, but i have a little experience.

I must say, they are looking real good.

Hope some of you vets can shed a minute and give some advice. It would be much appreciated. Thanks.

Each node below the cut will grow two branches, so at 4-5 nodes, you're in a good place to top. Or you could wait longer, that's up to you.

They should probably be bigger than 6-8" after 6-7 weeks of growing. You may have an issue in your medium to deal with.

smokinrav said:

Each node below the cut will grow two branches, so at 4-5 nodes, you're in a good place to top. Or you could wait longer, that's up to you.

They should probably be bigger than 6-8" after 6-7 weeks of growing. You may have an issue in your medium to deal with.

Click to expand...

I did a little more math. It has been more like 4-5 weeks. Definitely no more than 5 weeks. The first two weeks were under flourescent T8 strips.

I am just now feeding them at half strength. Every three-four days. Soiless mix, with canna substra.

So you think just above the 4th or 5th node? Going for short and bushy.

I read a thread by the Uncle Ben charachter who talks about cutting above the 2nd node to make 4 tops. It is at the top of the Advanced cultivation techniques. Uncle Bens Topping Techniques.

I like to hear lots of opinions. Thanks for the advice. If you have any more advice to give I would apprectiate it.

here's a good guide for making mothers. not exactly what you're doing but you can apply it to your situation.
http://www.icmag.com/ic/showthread.php?t=31919