Tender spears nosing their tips up through the soil in spring, cut low with a long-bladed knife: asparagus (Asparagus officinalis) is grown for its subtle taste and soft flesh, and for its high vitamin C. Give it light, sandy, well-drained ground and never let water sit, and a bed will crop for over fifteen years.
| Name | Asparagus officinalis |
|---|---|
| Family | Asparagaceae |
| Type | vegetable, perennial |
| Height | 30 to 55 inches (80 to 140 cm) |
| Exposure | full sun |
| Soil | light, well-drained |
| Harvest | In spring, when the shoots sprout from the ground |
Even though the different varieties are labeled “early” or “late”, asparagus are usually eaten in spring. Follow our advice to get a nice harvest and avoid disease.
There are 2 main types of asparagus:
You can grow both types in exactly the same manner.
During the months of Late winter to mid-spring, it is important to plant asparagus in rows, preferably aligned with dominant winds.
Asparagus is demanding and it is necessary to fertilize the ground beforehand.
Plant asparagus thanks to young root clumps grown from seeds, called “crowns”.
If you’re preparing seedlings, wait for a year before putting them in place.
Asparagus needs 2 years to grow since harvesting isn’t possible during the first year.
To speed things up, it is possible to purchase plants that are already 2 years old.
Once well settled-in, you’ll be able to harvest your asparagus for over 15 years.
As for watering, asparagus needs water on a regular basis but hates sitting water.
Asparagus must be harvested while still tender, and you cut it off with an asparagus knife.
The best time to harvest asparagus is from Mid-spring to early summer. Harvest shoots with a long blade-tipped tool called an asparagus knife.
Tip: It is best to wait a full 3 years before harvesting your asparagus, to let the plant develop during the first years of its life.
Crowns are bought once and cropped for fifteen years or more, so the choice of variety matters more than with any annual vegetable. The table below sets out the cultivars most often offered by garden centres and mail-order nurseries, with the points that separate them.
| Variety | Spear colour | Plant type | Cropping season | Best for |
|---|---|---|---|---|
| Purple Passion | Deep purple | Open-pollinated, mixed sexes | Mid-season | Sweet spears eaten raw |
| Pacific Purple | Purple | Open-pollinated, mixed sexes | Mid-season | Salads, low-fibre thick spears |
| Mary Washington | Green | Open-pollinated, mixed sexes | Mid-season | Raising from seed cheaply |
| Early Argenteuil | White, purple tips | Open-pollinated, mixed sexes | Early | Blanching under ridged soil |
| Jersey Knight | Green, purple bracts | All-male hybrid | Mid-season | Disease-prone gardens |
| Jersey Giant | Green | All-male hybrid | Early | Cold northern gardens |
| Jersey Supreme | Green | All-male hybrid | Early | Light, sandy ground |
| Connover’s Colossal | Green | Open-pollinated, mixed sexes | Early | Reliable all-rounder, light soils |
| Gijnlim | Green | All-male hybrid | Early | Heavy early cuts, uniform spears |
| Backlim | Green | All-male hybrid | Late | Thick spears, extending the season |
| Guelph Millennium | Green | All-male hybrid | Late | Cold areas and late frosts |
| Martha Washington | Green | Open-pollinated, mixed sexes | Mid-season | Traditional beds, rust-prone sites |
| UC 157 | Green | Hybrid | Early | Mild winters and warm regions |
Beyond the familiar green and white spears, two further types turn up on stalls and in kitchen gardens. They differ mainly in thickness, in whether they need peeling, and in how they are best eaten.
| Type | Taste and texture | Peeling needed? | Notes |
|---|---|---|---|
| Green | The finer tasting one | No | Doesn’t grow as deep, so a long kitchen knife is enough to harvest it |
| White | Thicker spears | Yes, always | Rather common |
| Purple | Close to green asparagus | No | A rare variety |
| Wild | Thin and delicate | No | Perfect in mixed salads |
Whichever type you choose, the taste finally depends on the soil it grew in.
This vegetable has high vitamin C levels and nutrients, but actually, the delicate and subtle taste and soft flesh turn it into a delicacy.
Asparagus grown today were bred from an ancestor called medicinal Asparagus.
The taste of asparagus essentially depends on the type of soil and organic matter content.
Clay and loamy soils will give it a rather bitter taste.
Together with the green and white varieties, you’ll find a couple others, too:
To taste them at their best, eat them quickly after they’ve been cut.
Add compost in fall to increase availability of nutrients.
