It is possible to start an asparagus bed from seed. You will not get a harvest until the third growing season. Asparagus crowns offered on the market are usually one or two years old. When I buy them I like the two year old crowns. The growers have started with seed. The little frail ferns need to be carefully weeded and cared for. Two years later they dig them up and sell them. Its no wonder they want a high price for them. The two year old crowns do not give a harvest the year of planting, but will give a harvest the following year. The beautiful thing is that once you have an established bed, it will last for many years. If you plan to stay on your plot long term, it is worth it to start from seed.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-