I've rushed transplanting seedling cactii, and let them sit till they were touching and crowded. They don't seem to care. The size you can work with is probably my best advice.
so there good to stay in my propagator until their a good size?? i like the sound of that. . i have the fingers of something with very large fingers and find pricking out a task. the cactus don't look to fragile though, they've come through quite chunky. i think i could handle it without squeezing the life out of them :-D p.s thanks guys :-D
When pricking out seedlings it important to remove the seedlings before the roots become entangled. This assures that you retain the best root structure as you put the plant in its new home. A pricking tool is helpful. In a pinch the back end of a spoon works, or a wooden ice cream spoon. The first one out is the hardest. Jerry