The first and most appropriate way is to dig a trench 12 inches deep. Line the bottom of the trench with a layer of good soil and compost. Then plant your plants and as the summer goes on and the asparagus starts to grow you fill in the trench and by the end of summer the trench is filled in and the stalk is out of the ground.
The second way is the way i planted my asparagus plants for this instructable. My soil isnt the greatest ,It has a lot of clay and is a little wetter than i like for growing asparagus so i went the above ground way.
Asparagus starts coming up the beginning of may and should stop being harvested at the end of June.After june let the stalks grow and go to seed. They will develope little red berries and the top of the stalk. These will fall off and create new seedlings.
After this happens the stalks will dry up and now is the time to cut them down and put a layer of mulched leaves over the bed of asparagus.
Choose a good fertilizer with higher phosphate and potassium levels. A good formula is 10-10-10 which a good time to fertilize is in the hot months of july and august.
Good luck and happy gardening....
Step 1: Materials
80 Asparagus plants
15 bags of rich moist compost soil