Good question.
All of our hybrids are packaged in bags of 25 pieces. We sell anywhere from 25 pieces to 1000 pieces on any given order.
The "Other" willows are generally sold to home owners / landscaping type people that don't want nearly as many. In the past we sold these willows in quantities of 5 pieces. I upped it to 10 pieces because as an example people were ordering 10 different willows at a quantity of 5 pieces each for a total of 50 pieces. It takes quite a while to sort/bag/label/package each one. And in the end the order was only for 50 pieces. The order value to effort ratio was out of wack :) Hopefully quantities of 10 pieces helps fix that.
Hopefully that answers your question.
Thanks,
-John