Not usually planted from seed, but final plants should be 12" apart.
Seeds Per Ounce
Space Between Plants
All male: Jersey Giant, Jersey Knight, Mary Washington
Traditional: UC 1547 F1 - (large, pale green spears) Purple Passion (Large dark purple spears)
Seed Viability (Years)
53 days at 50° F 24 days at 59° F 15 days at 68° F 10 days at 77° F 12 days at 86° F 20 days at 95° F 28 days at 104° F
Plant asparagus in organic, rich, well-drained, sandy soils. Asparagus grows best in soil rich in organic matter. Dig a bed 12" deep mixing in 4" of organic matter.
Asparagus should be cared for with sufficient water in an area that allows for adequate drainage.
Quality 1-year-old crowns with 8 to 10 large roots and a healthy bud cluster will allow you to plant and begin harvesting in the same year - planting from sees will take at least a year before any significant production will be seen.
Asparagus should be planted in the early spring several weeks before date of last frost. To plant asparagus, soak the roots in warm water for a couple of hours and then place the crowns 6" to 8" deep in furrows, spreading the root in all directions. The crowns should be placed about 12" apart in rows about 48" apart. Cover the crowns with 2 inches of soil and gradually add back more soil through the season as the plants develop. As you bury the plant roots, take care not to cover the tips of the spears. Asparagus should not be harvested during the first year.
According to research at Rutgers University in New Jersey, asparagus seeds can be started indoors 12 weeks before planting outdoors, and then planted later in the season after danger of frost. In the study, plant production began in the second year.