hahahaa...I've done the straw bit meself buk. Keeping it from slipping is a drag. More like a splint than a brace that way. (fyi...having to go through a thing like straws and toothpicks...sucks ass. Not wanting things to suck ass makes for paying proper attention to getting seedlings off to a healthy start.)

btw...dryst, eats easy enough to find something handy....chopsticks, a whole straw pushed down far enough...a skewer ffs. Small diameter thing though, keep a mind toward not hacking through root.