Krista I alternate between a Jack's All purpose fertilizer that comes as blue crystals you disolve in a pail or water, and my other go to is a fish fertilizer. I Also give the beds the amendments reccommended by my yearly soil tests when I plant them in spring. My raised bed soil is a purchased organic garden soil so was pretty much in balance to start with but I test yearly to make sure I keep up with any changes. My soil started out a bit too high in organics so the only other thing I add is that handful of alfalfa pellets when I plant the tuber. I think the plants look good, better each year now. And after our very sad year with the heat domes ,2 years ago the plants AND Tuber production were back up last year.
As to the fertilizer injector it was most likely from Drip Works. So it fit into the whole set up for the beds where I use the little downsprinklers coming off the main lines.
