How long to cure?

Throw Sand On The Material And Tamp It Over Until It Is Solid.

A few tips from experience: 1. Clean area of loose material, if you have filled already then this is moot 2. Add material about 1" above finish grade then compact with flat shovel to grade (play wack-a-mole) 3. Drive over with vehicle tire at 45deg angles to further compact 4. Using a light application of rock dust last does cut down on the stickiness 5. Curing can take several weeks of 70degF plus temps. Conditions vary with climate. If QPR is crumbling, then asphalt adhesive chemicals may have dried out. This consistency of QPR does not work on small cracks. Goey is good. Hope this helps

Wait till it is about 75 degrees at least

I have used this product for some 2 inch deep bird bath depressions and found that it stayed tacky for about three months. I dug it out to replace with another type of repair product and the material under the crust never hardened after a full year. A sand or dust topping may help the tracking of the filler, but will not speed the cure time as it may never harden. Think of it this way, it stays soft in the bag at room temp, you are only exposing it to the air after you use it with no real change in temperature. A tar product alone will not harden when exposed to air, only a skin will form.