Stop cutting when most of the spears coming up are thinner than a pencil. That is an object to look for, not a date to circle. A new bed in the Northwest Territories also gets no cutting at all until its third year, and then only four weeks of it. Cut spears keep best at 0 to 2°C (32 to 35°F) with their butts standing in water. The ground, the watering and the planting date behind that harvest come next, and the wider picture is in Growing Asparagus in Northwest Territories.
The short answer
The ground comes first, because asparagus is a fifteen-year decision. Crowns go into 8-inch (20 cm) furrows in early spring, nothing is cut until year 3, and then the bed produces for 10 to 15 years. Utah State University Extension, the only authority behind this page, sets one soil requirement: the ground must drain. Most soils will do, provided they do.
What the dominant soil says
Across the 80 mapped surface horizons in the Canadian soil survey for the Northwest Territories, the commonest soil is a Cryosol. That is a soil with permafrost somewhere in the profile, where the ground thaws only to a shallow active layer each summer. Cryosols cover 99 percent of the mapped surface, with Regosolic soils next. The typical surface is loam to silt: 55 percent sand, 6 percent clay and 39 percent silt, with organic matter around 2.4 percent, and the survey classes it as well drained.
So does it drain well enough? On paper, yes. Six percent clay is nowhere near the heavy, sticky ground that ruins an asparagus bed. The catch is the frozen layer beneath. Water cannot pass down through ice, and a furrow 8 inches deep needs thawed ground at least that deep. The survey does not say how deep the thaw runs at any given spot, so that is something to check on your own plot.
Treat all of this as a starting point, not a diagnosis. The survey covers the agricultural regions only, so the far north is not represented. River bottoms, muskeg and any lot a builder has scraped or filled will behave differently. No median pH is published for this surface, and the extension source is silent on pH as well, so there is no number here to borrow. A soil test on your own ground is the only way to get yours.
What to do if the spot does not drain
Dig a hole about as deep as the furrow, fill it with water and look at it the next day. Standing water a day later is telling you something. Elsewhere on this site a heavy soil is an annual nuisance you amend each season. Here it is a decision you live with for up to fifteen years, so the fix happens before planting. Build the bed up above the surrounding grade, or move it to higher, better-drained ground. The longer reasoning is in Will Northwest Territories Soil Hold an Asparagus Bed for Fifteen Years?
Will the summer here water it for you?
What the summer delivers
Not enough to leave it alone. At the Yellowknife A station, Environment and Climate Change Canada’s normals put June, July and August together at 109 mm (4.3 inches) of rain, out of 290 mm (11.4 inches) for the whole year. June is the driest of the three at 29 mm (1.14 inches). July brings 41 mm (1.61 inches) and August 39 mm (1.55 inches). These are 30-year normals from an older reference period than the US figures on this site, so do not set them directly against a US number. One station is also not a territory.
The bed wants 1 to 2 inches (25 to 50 mm) every other week for the first two years, then every three weeks. A summer of about 13 weeks holds six or seven two-week stretches. Spread evenly, the rain hands the bed roughly two thirds of an inch (17 mm) per stretch, leaving a gap of a third of an inch to a little over an inch (9 to 34 mm). After year two, a three-week stretch collects about an inch (25 mm) of rain, so the gap runs from nothing to about an inch. That is my arithmetic from the normals, not a published recommendation.
The real gap is probably wider. A loam to silt surface lets rain through faster than clay would, and rain that arrives as one hard summer storm tends to run off rather than soak in. The normals describe what the region can usually expect, not what your plot receives.
Working out your own top-up
- Set a straight-sided rain gauge in the bed itself at planting. A slope, a windbreak or a nearby building can change what lands there.
- Add up the rain over each two-week stretch for the first two years. If the total falls short of 1 inch, water the difference by hand, and aim closer to 2 inches in a dry stretch.
- Water slowly and once, rather than with a daily sprinkle, so the water reaches the crowns instead of wetting the top inch.
- Expect to add the most in June, the driest month of the three.
- From the third summer, run the same count over three-week stretches instead of two.
When to put the crowns in
Around May 25, and not before you check
Crowns go in during early spring. For this territory, the anchor is a last spring frost that falls, on average, around May 25 at Yellowknife A, according to the same Environment and Climate Change Canada normals. That is a mean date, not a safe one. In one year out of two the last frost lands later. Read it as the middle of a window and watch the forecast.
It also comes from one station. Northern and upland districts run weeks behind it. Because the furrow is 8 inches (20 cm) deep, the soil has to be thawed to at least that depth before you can dig it. The published guidance gives no frost tolerance for crowns, so I will not invent one.
Once the crowns are in, the furrow is not filled all at once. Backfill it gradually across the year, 2 inches (5 cm) at a time, every other month. Then comes the wait. Nothing is harvested until year 3. After that the first cutting lasts 4 weeks, the next year 6 weeks, and the year after that 8. Do not soften it into a few spears here and there, because the crowns are still building the root mass that carries the next decade. Pests are a separate question, covered in What Eats Asparagus in Northwest Territories, and When.
Crowns, seed and the four named varieties
Seed is the alternative to crowns. The source behind this page builds its schedule on crowns and publishes no seed dates or harvest timing, so I will not make any up. Plan around the three-year wait unless you find a seed-specific schedule from a reliable source.
The extension source names four varieties and gives only their sex. Jersey Giant and Jersey Knight are all-male. UC 157 F1 and Purple Passion are male/female. No flavor, yield or reason to prefer one is published, so nothing here ranks them. No nursery is named either.
Common questions
When do I stop cutting each season?
Stop when most of the spears coming up are thinner than a pencil. Do not convert that into a week number. Spears that thin mean the plant needs its ferns to feed the crown, and the bed’s 4, 6 and 8 week limits are ceilings, not targets.
Can I take a few spears in the first two years?
No. Nothing is harvested until year 3. The first harvest runs 4 weeks, the next 6, and then 8.
How do I keep cut spears fresh?
The target is 0 to 2°C (32 to 35°F) with air near saturation, at 95 to 100 percent humidity. Both edges of that window bite. Above 10°C (50°F), UC Davis Postharvest reports, spears toughen within hours. At -0.6°C (30.9°F) or lower, freezing injury turns them water-soaked and extremely soft. In a home kitchen, stand the butts in water, since the cut end loses moisture faster than anything else, or wrap them damp.
Does the soil survey tell me whether my garden drains?
It tells you what the region’s ground tends to do, which is drain, with permafrost beneath. It does not tell you what your plot does. Test the drainage in a hole, and get a soil test for your own pH, because none is published for the mapped surface.