Asparagus is most productive on deep, well-drained, sandy loam soils. The plants lose vigor, become more susceptible to root rot, and die in poorly drained areas or following prolonged high rainfall. Medium fertility is best it produces a balance between top growth and root growth. The Horticultural Standards of the American Association of Nurserymen are often used to identify the size of crowns. 3-year crowns may be used.
Larger crowns have more vigor.
It is difficult to get commercial crowns free of Fusarium root rot. One way to avoid Fusarium is to plant disease-free seed and grow your own crowns or seeding transplants. Crowns are produced by seeding in a nursery about two weeks before tomatoes are normally transplanted into the garden. Sow 3 to 4 seeds for each crown you want to plant in the permanent bed. The following spring, when the ground has thawed but the plants are still dormant, carefully dig the crowns to minimize damage to the root system, and immediately plant them in the permanent bed.