quirkpod,
How much do you use and how? I have already planted a couple of trees. Is it too late to add it to the top of the soil?
As far as locating it ,have you tried your local nurseries?
My big box stores do not carry it but I saw Hi yield super phosphate at a local nursery .I am in SC though.

Do you have any farmer supply or feed n seed type stores? They usually carry it. The big box stores (Lowes, Home Depot, Walmart) carry it 'sometimes' too. I think I've even seen it at the Tractor Supply place. Sometimes it depends on the time of year. If they're out of it for the season they may not order again till spring. We were looking for permatil the other day and were told they were out and wouldn't reorder it till next year. Try calling around first.

I know here in Raleigh Atlantic Avenue Garden Center has it because I bought some there, so maybe one of the garden centers around your location has it also. You may have to pay a little more, but you would still have it until you could locate another supplier.

I had no idea this stuff was good for using at planting time. I have never known what it is for.. can you tell me how much you put and everything? I think I can find it at my local feed & seed store.

One garden center around here recommended to me when planting trees and large shrubs to mix a handful (cup?) in with organically-mixed planting soil, then mix that with the out-of-the-hole soil. Pour a 2-gallon mixture of root stimulator into the hole with some of the soil mixture, set the tree/plant and then add the rest of the soil. They say if this is done you will never have a bad result...even though most notable sources say to NOT add anything to the planting hole. Go figure??

I've done the above with several plantings this year with great success.