Last year I used Jiffy Mix and had no problems germination wise.But there was all kinds of sticks,and twigs in it.Think I even found a '68 Chevy bumper near the bottom of one bag
.This year my wife got me 2 Ferry Morse Mix bags, and very few sticks and twigs.On the Jiffy Mix, I added some Perlite last year,this year I didnt add it.I found no difference in germination.But Im sticking to the Ferry Morse brand for sure. Barry