We grow a fair amount of asparagus. Like most people, we ordered year old crowns to get started. We grow Jersey Knights. Many growers will tell you they are sending all male plants (which spend their time making fat asparagus spears instead of diverting energy into producing fruit like the female plants).
You plant them in a trench with the roots splayed out. For the first two years, you should just let them all grow. The third year after planting, you can starting cutting them for eating as they come up in the spring. Cut the ones that are at least the size of your little finger. After about 6 weeks, don't cut any more and let them grow out. In the late fall, cut the dead foliage down to ground level, put down some fertilizer and cover them with some straw. They'll just come up right through it the next year. Weed them well, as they don't like competition.
Even though the grower promised all male plants, they were not, in fact, all male. We have two female plants, so they set fruit - little red berries. Two years ago, I tried an experiment. I collected the seeds from them at the end of the season. Last spring, I started those seeds indoors and they germinated. I put the seedlings out to my garden in a new spot, where they grew. They survived the winter and are coming up again this spring. With them, it will probably take four seasons to get edible asparagus instead of three, but it was cool to see that you can actually grow asparagus from seed.