The two most common questions I get about growing asparagus:
- Why is my asparagus so skinny and poor?
- How do you grow asparagus?
I grow asparagus by first selecting a well-drained area away from trees. Next, I take a soil sample (Get information on how and where to send samples at your local library or through the Virginia Cooperative Extension.). Third, I apply the recommended amendments to the soil and plow in.
Planting asparagus
I open a furrow approximately 8 inches deep. In addition to soil sample recommendations, per 100 feet of row, apply 20 pounds of 5-15-20 plus trace elements (tobacco-type fertilizer), 30 pounds of gypsum (contains large amounts of sulfur and calcium), and 30 pounds of dolomite limestone (contains large amount of magnesium) on the bottom of the furrow. Work it into the ground with a hoe fork before placing the asparagus roots into the furrow.
Asparagus is a salt-tolerant plant. Once the fertilizer is worked into the ground with a hoe fork, no salt damage from the fertilizer should occur to the asparagus roots.
This is your last chance to apply nutrients directly into the root zone for the life of the asparagus roots, and that should be at least 15 years. With this extra fertility available in the root zone, your soil should support “high density” asparagus.
Protecting asparagus plants
I lay the roots in the furrow one on top of the other, like dominoes, with the crowns 7 inches apart. I don’t spread the roots out or apart, but you can if you like. One long single row is best, because you can mow the weeds off on either side of the asparagus right up to where the stalks come out of the ground without injuring the asparagus.
Drive the lawnmower in the direction that would expel the cuttings away from the row of asparagus.
Asparagus shoots are very tender, and the force of the cuttings hitting the asparagus will make them grow crooked. Some people like crooked politicians, but nobody likes crooked asparagus. Also, a single row allows for better air circulation, helping to minimize disease.
A single row also results in better yields because of more sunlight per plant. And more asparagus in the row competes more effecitvely with the weeds within the row of asparagus along with manual weeding.
Plant asparagus away from trees
When people say their asparagus is skinny, I ask them if they planted it near trees. Nine times out of 10, they say yes. By “near trees,” I mean close enough to either be shaded by the trees during the day, or to have roots that reach the asparagus bed.
Remember, an asparagus bed should last at least 15 years, so look around, and if you see trees, imagine how big they’ll be in 15 years.
Asparagus cannot compete with trees for sunlight, moisture or nutrients in the soil.
My grandfather would dig a trench a foot deep below where the asparagus was to be planted and fill it with well-rotted cow manure mixed with dolomitic lime and gypsum. You may do this if you like (or if you want organic fertilizer). I find it to be too much squeeze for the juice. Using commercial fertilizer, especially with five or seven different trace elements, is much more effective.