Photo Credit: Emily Bulmer
The asparagus exSPEARiment: Once established, this tender perennial is a welcome addition
I cuss, you cuss, we all cuss for asparagus! Well, maybe the melodious sounds of the asparagus truck isn’t exactly a reality in your neighbourhood, but that doesn’t mean there is any less joy when the first green tip of an asparagus spear breaks the warm spring earth.
Most vegetables taste better when grown close to home and for asparagus this is especially true. If you think you don’t like asparagus, try some from a farmers’ market or your own backyard and you will be amazed. No fibrous strings, no bitter taste: homegrown asparagus is melt-in-your-mouth sweet and needs almost no dressing up.
Dave Cody knows asparagus better than many, having spent 37 years growing it on his Telkwa farm. Last year, he grew 350 pounds. He has about 50 regular customers and distributes his product at local drop-off points. The demand certainly outstrips supply, so if you can’t get your hands on Cody’s asparagus, you can start a crop of your own. Growing asparagus at home is a long-term project, but one that is well worthwhile.
Seeds or transplants
An asparagus bed can be started from seed or from transplanted crowns. Asparagus started from seed is very small and fragile for at least a year, but can be started in a container for added protection. Once sprouted, they are so small they look like grass. Make sure the soil is well drained and has plenty of nutrients to feed the young plants. When fall comes, sinking the container deep into your garden adds extra protection from the cold. The following season you can transplant the tender shoots into a nursery bed.
According to Cody, the best way to prepare asparagus beds is the “trench method.” Using a rototiller, hoe or spade, dig a trench about eight inches deep. Fan the crowns on top and roots in the bottom of the trench. Backfill the trench gradually with compost and organic matter, burying the crowns over the course of the season.
“This gives the crown the ability to put roots down deeper, which prevents winter-kill,” Cody says. “I’ve experienced probably five years of winter-kill (and lost) 20 or 30 crowns—it is kind of heartbreaking after all that work. Frost will heave the plants closer to the surface, which also increases the possibility of winter-kill.”
To avoid winter-kill, ensure you have well-drained soil, a thick layer of mulch and snow cover, if possible, to provide extra insulation from the cold. Cody advises keeping the earth flat around the crowns rather than mounding: “Water will run off the mound and won’t be evenly distributed in your bed,” he says.
Once in place, ongoing maintenance consists of feeding and weeding the crop.
“Asparagus is a heavy feeder,” he says. “They are up there with corn. You have to feed it or you pay the price.”
He uses a combination of compost, fish fertilizer, slow-release organic fertilizer and dolomite lime.
“I also save the ashes from the woodstove to maintain a pH of around 7 and keep down some of the weeds that don’t like ash.” He no longer uses manure: “I used manure one year and the result was a wicked crop of sow thistle. Now there’s Grazon (a herbicide) I have to look out for, so I stay away from manure.”
Cody recommends using a heavy mulch to keep the weeds down. In about two years, once the mulch has decomposed, add a slow-release fertilizer, then lay more mulch on top.
“Asparagus is pretty carefree once you get it established. Past the third year (it does) appreciate the care and will pay you for it in the future.” He recommends new growers “keep it small so you can tend to it and keep up with the weeds.”
Pests are not a problem, according to Cody.
“The asparagus beetle hasn’t made the journey this far north. I think it is too cold here for it to survive the winter.” Anthracnose is a fungal disease that can affect asparagus, presenting as rust-coloured foam and difficult, if not impossible, to defeat, according to Cody: “Remove the plant and burn it. Once it is in the soil, there’s not much you can do.”
Cody grows three varieties: Mary Washington, Viking and Guelph Millennium. “I lean towards the hybrid, all-male varieties—they are the heavier producers. I tried the purple variety two years in a row and they all died. I tried the white and it didn’t do very well, either.” Since 1977 he’s tested about nine varieties. “I’m sticking to the three I have for now. They work well on this farm.”
Asparagus is a perennial, so it cannot be completely harvested. Cody says, “Always let some stems grow—that’s what feeds the root system. Leave them to grow through the fall and they get knocked over in the winter. The foliage is dead and crispy in spring after it has dried out. We clip and burn them and then reintroduce the ash back into the ground.”
He recommends harvesting conservatively until the third year.
“A normal crown will produce 20 to 30 spears once it is established and you want to leave 10 to 15 percent for the plant to nourish its roots. As time progresses past the fourth, fifth and sixth years, you can cut more heavily.” Like most perennial plants, eventually asparagus needs to be divided. “You should divide the older crowns at about seven or eight years.”
A relative of the lily family, asperagus is treated in the same way: Once lilies become over crowded you have to divide them so they keep on blooming. Happily, this means you have more asparagus to expand your bed or to give away to your friends.
When cutting the asparagus to eat, store it tips up in a jar or plastic bag with some water at the bottom—just like flowers. “You can trick them in to thinking they are still alive and they will keep for about seven days,” Cody says.
Asparagus is fantastic steamed, grilled or lightly stir-fried. Although it is a long-term gardening project, the tender, green shoots are worth it. If you share a bit with your friends or pass on a crown or two, it is a treat that can be paid forward and your friends might not be so green with envy.