Rich in iron, calcium, vitamin C and B vitamins, asparagus is one of the first crops to be harvested in the spring and if given the proper planting and care, an asparagus bed can be productive for 15 years or more.
The asparagus bed should be located in a sunny area. It can tolerate a little shade but the plants will not be as vigorous and full sun helps minimize the threat of disease.
The soil will need to have a pH of 6.5 to 7.5 and be well drained as soggy soil will cause root rot.
It is best to have the soil tested as asparagus will not grow well if the soil pH is less than 6.0 and the levels of potassium and phosphorus are also important to the vigor of asparagus.
Asparagus can be planted mid-April thru late May after the soil has warmed up to about 50 degrees. Dig a furrow about 6 to 10 inches deep and 12 to 18 inches wide. Apply to the bottom of the furrow about 1 pound of 0-46-0 (triple superphosphate) or 0-20-0 (superphosphate) fertilizer for every 50 feet of row. This will make phosphorus available right away to the newly planted crowns. Planting 1 year old crowns will produce a quicker crop than sowing seeds. Space the crowns about 1 ½ feet apart in the row. The crowns need to be centered in an upright position in the furrow and the roots spread out. If more than 1 row is planted, the rows should be spaced about 5 feet apart. Wide spacing promotes the rapid drying of the fern tops to help prevent disease. After the furrow is filled back in to its original soil level do not tamp it down. Asparagus likes loose soil.
Do not harvest the asparagus shoots during the year it was planted. The ferns that emerge from the spears produce food for the plant and move it down to the crown for the next years spear production.
Asparagus is very drought tolerant and usually does not need any supplemental watering. However, if rainfall is short after planting, a little watering would be beneficial to the crowns.
Do not cut the fern growth at the end of the growing season. Leaving it intact over the winter will catch snow for additional soil moisture and provides insulation for the crown. Remove the old fern growth by cutting or mowing it off about the first week of April.
As always, Happy Gardening!
The Purdue University Cooperative Extension Service can be reached at 499-6334 in LaGrange Co.