Plants are avg 18" tall I'd say in 1-1.5 gallon pots. They've been in there for 4 weeks or so.
I killed some males last weekend and did examine the soil and roots. The soil was encompassed entirely by the root mass and was very solid, but I'm guessing that is by design, and I've done a good job with wet/dry watering so the roots have gone on a growth quest for water on a number of occassions.