Go to the Indiana Berry Company web site. They sell year old asparagus root crowns - what you want to plant. The have good information on growing, what works best in what kind of soil, etc. Prices are good -25 crowns for about 25.00. And they will be healthy. However, their shipping season is over until next spring.
FWIW. I work in a very large retail greenhouse which also sells to landscapers, etc.. We buy most of our asparagus, rhubarb, strawberry, etc. bare root stock from Indiana Berry. We pot 'em up in late winter/early spring and let them grow for sale a couple months later. I have personally ordered from Indiana Berry, too, for my own garden. My asparagus bed is almost 25 years old now and quite healthy. It is at the far end of a long flower bed. The ferns are summer backdrop for other flowers, etc.
Prepare your bed for the asparagus this fall - dig deep, good soil amendments, manure if you can get it, and get your order in for spring. You might be able to find some roots potted up in your local greenhouse which have been growing in pots since Feb/Mar. They will be much more expensive than starting from fresh bare root next spring. And yes, asparagus likes as much sun as it can get.
= new reply since forum marked as read