internode spacing

Besides genetics what is the best way to keep internode spacing tight? Are there any products on the market to help achieve this?

keep the light as close as you can, or put lights on the side.

MH light in veg is supposed to keep internode space tight.

Lights as low as you can. I use T5 and almost tuch the tops.

Keep your lights as close as possible, there are no products to control internode spacing.

I agree. I'm using four 23 watt cfls and my nodes are so tight it's difficult to LST my girl right now. It's all about keeping the light close.