soonami

I've done this technique popularized with JBPs on Japanese maples, and I have to say that it is a fantastic way to get good root spread.

I cut the seedlings about 1cm below where the cotyledon are attached when the first set of true leaves open and as the active growing bud is extending. I try to be clean with the cut, using a sterile razor and dip the ends in talc-based rooting hormone. Then stick into to porous medium (75% turface, 25% bark) and keep in indirect light, protected from wind. In about a month, those that worked will grow roots and those that haven't will just wither and die. In late spring, around mid-May here in Phila, I transplant into 4 or 6 inch pots and let them grow.

If you aren't sure if they will work, just cut half and let the other half do their natural thing