Calendar of Events

Saturday, August 17, 2019

Growing Asparagus Requires Planning, But Gives Many Years of Reward

Asparagus is a shining gem of springtime in Southwestern Idaho. Packed full of nutrition and boasting a delightful flavor, asparagus will give you 15 years or so of production from one well thought out planting. When mature, one plant produces about ½ pound of asparagus a year. It is an early producer, so you can plan on fresh vegetables gracing your table much sooner than neighbors who haven’t established asparagus in their garden planning. Getting this productive perennial started growing in the right spot and with the right preparation, is the most important step for the home gardener with regard to their plans to grow asparagus. 

Where to Plant?
Due to it being a perennial, planting it at the side or center of your garden can be ideal so it doesn’t interfere with plot preparation and cultivation of annual crops. It can grow to a height of 3 to 8 feet tall, so a bed on the north or east side of your regular garden plot in a spot that gets approximately 7 hours of full sun each day is ideal. Because asparagus roots can be deeper than 6’, even raised beds are an option. Consider that a 25’ to 50’ row will supply the typical family with enough asparagus for regular use.

Site Preparation
Asparagus prefers deep, well-drained loam or sandy loam with a pH of 6.5 to 7.5. If the soil retains too much moisture, asparagus can die from root rot. It will grow in soil conditions that are not ideal, but the life of the plant and the production will be reduced. It is best to begin site preparation in the fall by breaking up the soil to around 18” deep and working in rich organic matter like mature compost or aged manure. Simultaneously, add 4 to 5 pounds of 5-10-10 fertilizer per 100 square feet. Prepare an area that is 3’ to 4’ wide and as long as necessary to supply the amount of asparagus you wish to reap from your harvest each year, after plants mature.  

Planting
You can start growing asparagus from seed or crowns. Most choose to start with one year old crowns to get to harvest faster. Choose large crowns that have not dried out - male crowns are more productive than female crowns. Older crowns can be purchased, but they are more expensive and much harder to plant successfully. If you are working with prepared good soil, dig a trench 12” to 18” wide and 6” to 8” deep. If you are working with heavier soil, use the more shallow depth. Spread mature compost or aged manure in the bottom and cover with about an inch of garden soil. Place crowns in trench about 18” apart, while spreading roots to insure they lie flat. During the growing season, continue adding soil or aged manure until the trench is full, being careful not to cover foliage. 

Maintenance
For ongoing high spear yields, it is recommended to fertilize before plants start growing each spring and again in the fall after harvest using 1 ¼ pounds of 5-10-10 fertilizer per 100 square feet each time. A deep watering once every couple of weeks during dry season is plenty due to the deep root system. Weeding should be done somewhat regularly, but do not cultivate deeply as you can encourage disease if crowns are damaged. Adding a thick layer of mulch will help reduce weeds. You may use herbicides approved for asparagus, but mulching and hand cultivating is favored. Take the time to learn about dealing with pests like Asparagus Beetles and diseases like Fusarium Wilt and Root Rot.

Harvest
The reward for taking the time to plan and prepare your plot, and the patience you exhibit for several years is the harvest! It is recommended not to harvest any asparagus until the third year to allow the crowns to be mature. You may remove a small harvest for approximately 3 weeks during the third year. You can harvest for 6 to 8 weeks for every year after that. Harvest in the morning when spears are crisp. Spears should be 5” to 7” when harvested. Snapping the spears is advised over cutting to avoid damaging emerging spears. Refrigerate spears promptly after harvesting. An excellent, simple recipe for asparagus is Oven Roasted Asparagus