Jeff Green | May 21, 2009
Back to HomeMaster Gardeners - May 21, 2009 Asparagus – an easy perennial
by Lorri Mackay, Lanark County Master Gardeners
Fresh asparagus from the garden beats out super market stock for taste and tenderness any day of the week. And what’s more, asparagus is among the easiest of vegetables to grow. Asparagus is perennial, and while it takes a few years to mature, once it is old enough to harvest, all you need to do for the next two decades or more is to weed, mulch, compost and enjoy.
Asparagus can be started from seed or from year-old roots called crowns. Seed is the cheaper route, but means waiting an extra year before being able to harvest. With either option, look for varieties resistant to rust and fusarium wilt. Also ensure that the variety you select is hardy for your area.
Since asparagus has both male and female plants, you may wish to choose male crowns or seeds if possible -- they apparently live longer and because they don’t spend energy developing fruit and seeds, as do female plants, they produce more spears. On the other hand, seeds from female plants mean new plants to extend your crop or to share with others.
Asparagus ferns or foliage (shoots that are left to grow and nourish the roots) can reach about five feet tall, with a spread of three or four feet. So a generous plot in full sun is advisable – located where the ferns will not shade other crops. The most important thing is to ensure the plot is free of weeds – especially perennial weeds -- right from the start. Rich, loose, deep and well-drained soil will promote strong and healthy roots –and the happier they are, the more asparagus you get to eat.
If starting from seed, soak the seeds in luke warm water for forty-eight hours, and then sow them about a half inch deep. (You may wish to start the seeds in a small bed, planted quite close together and transplant the young plants to their permanent home in the fall.) Plant crowns directly into their permanent plot, buds pointing up, about six to eight inches deep and 1.5 to two feet apart. Allow three or four feet in between the rows.
Wait until the second year after planting crowns (the third year after planting seeds) to harvest. This gives the roots time to develop. The first year of harvesting, stop cutting after two weeks at the most. The following year, aim for about a month of harvesting. Thereafter, you can harvest for six to eight weeks.
Compared to other vegetables, asparagus has few pests and diseases. Adults of the two species of asparagus beetle (the common --Crioceris asparagi -- and the spotted-- Crioceris duodecimpunctata) will chew on emerging shoots, making holes and causing browning and scarring. The eggs of the common asparagus beetle attach to the spears, which makes them unappealing. When they hatch, the larvae eat the foliage, which can weaken the plant. (The larvae of the spotted asparagus beetle feed on the inside of berries, causing little damage.)
In either case, control asparagus beetles by removing spears that have eggs on them, hand-picking adults and brushing plants in the frond stage with a broom to knock larvae to the ground. In the fall, clean up the patch to remove over-wintering sites.
For gardening information, call Judy Wall at 613-267-6684.