Asparagus< - Illinois Vegetable Garden Guide - University of Illinois Extension



Since asparagus plants will occupy the same place for twenty years or more, the soil should be properly prepared and well fertilized before planting. Plants should be located where they will not be disturbed.

The roots or crowns used for planting are started from seed in the nursery the preceding spring. The larger crowns (8 to 15 per pound) are more productive and should be used if available.

Plant the crowns as soon as the soil can be worked in the spring. Set the crowns 12 inches apart in a wide furrow, about 6 to 8 inches deep. Cover them with about 2 inches of soil and gradually cover with the rest of the soil during the remainder of the season. Asparagus roots may spread out laterally for 5 feet or more.


Unless adequate space is allowed between rows, asparagus roots will compete with those of other crops for food and water.

Do not harvest asparagus until the third year it is in your garden and then harvest only during the first four weeks of the season. During the following years harvest up to the first eight weeks of the season and let the tops grow the rest of the year. Asparagus spears are ready for harvest when they are 6 to 8 inches long. Cut off the spear at the base with a knife or snap it off by grasping the spear near the tip. All of the snapped spear is edible, but the butt of the cut spear has to be trimmed off before cooking.

The asparagus tops can be removed or worked into the soil in early spring. The soil where asparagus is grown should be fertilized the same as the rest of the garden each year.

Crop Amount for 100
ft of row
Variety recommended for use in Illinois Days to harvest Resistant to
Asparagus (plants) 75-100 Mary Washington Rust
Waltham Washington Rust
Jersey Knight
Jersey Prince
Vegetable Hardiness Recommended planting period for central Illinois (b) Time to grow from seed to field (c)
For  overall
Asparagus Hardy Mar.15-Apr. 15 …….
Vegetable Spacing in row
Seed to sow per foot Distance between plants when thinned or transplanted Distance between rows Planting depth
inches inches inches
Asparagus ….. 12-18 36-60 6-8