It mostly depends on whether you meant "strive" or "thrive". If "strive" then just sit back, you're all good man.
However, if you want them to thrive.. How compacted is the soil? Was it pretty difficult to dig into? If so then you should cultivate wherever you want the roots to grow. If you plant the hops in nice loose soil and then the roots hit a bunch of hard compacted soil, it's like running into a brick wall. I think the soil amendments should be worked into the soil, sitting on top won't help the roots at all. The amount of soil amendments really depends on what the soil is like at this point and how much you want to be fertilizing in the future.
I don't know your specific situation, but I believe in most cases sand is not imported as a soil amendment. If you have clay soils, the amount of sand needed to change the soil texture into a clay-loam or something like that is often prohibitive. But like I said, I don't know your situation, maybe you have access to a ton of sand and have a way to easily incorporate it? If you do have heavy clay soils with a lot of sodium, consider adding gypsum as well.
Again, I'm not a hops farmer, but these are general agricultural practices. I'm also unclear if you are doing this just as a hobby or for actual production.