Growing Asparagus in Scotland: The Complete Guide

Asparagus officinalis

An asparagus bed occupies permanent ground for up to two decades once it's productive. Unlike most vegetables, which get replanted or rotated within a few years, the site and the variety are decisions you live with for fifteen to twenty years, so get them right before a single crownThe base of a perennial plant where roots and shoots meet, often sold and planted as a ready-made dormant plant rather than grown from seed. Full definition → goes in.

Perennial Vegetables Worth Growing in Scotland → compares asparagus against the other permanent-bed crops worth the same long-term commitment.

Crowns or seed

Plant one-year-old dormant crowns rather than sowing from seed: crowns settle in more successfully and reach harvest after two years, against three years (Gardener's World: at least five) from seed. Seed is cheaper, but on a crop where the first harvest is already years away, the extra wait is a real cost.

If you do want to raise plants from seed, sow indoors in February at 13-16°C, transplanting outdoors in early June after hardening offGradually getting young plants raised indoors used to outdoor conditions over 7–14 days before planting out, so cold, wind and direct sun don't shock or damage them. Full definition →, or sow outdoors March to April in drills 2.5cm deep, thinning seedlings to 15cm apart before moving them to their final spacing the following March.

Choosing a site

Choose a sheltered, sunny spot with free-drainingSoil that lets water pass through quickly rather than pooling, so roots aren't sitting in wet ground after rain. Full definition → soil (dappled shade is tolerated); on heavy soil use a raised bed. Avoid ground where potatoes have grown before. Weed the bed thoroughly before planting, and dig in at least a bucketful of garden compost or well-rotted manure per square metre.

Planting

Plant crowns in March. Dig a hole or a trench about 20cm deep, build a 10cm mound or ridge in the centre, and set the crown on top with its growing points uppermost, spreading the roots evenly down the sides. Cover so that just the bud tips remain visible. Space plants 30-45cm apart, in rows 45cm apart, staggering plants between adjacent rows.

Varieties

Gijnlim and Connover's Colossal carry the RHS Award of Garden Merit, a UK-wide award rather than a Scottish one.

Backlim and Guelph Millennium are also all-male with the AGMThe RHS's Award of Garden Merit: a UK-wide trials award for reliable performance, not a Scotland-specific recommendation. Full definition →, Backlim mid to late season. Pacific 2000 (all-male, well flavoured and late) and Mondeo (all-male, highly disease-resistant) are both H5The RHS's H1a–H7 scale for how much cold a plant can survive outdoors, H1a being tender indoor-only and H7 hardy anywhere in the UK. Full definition → hardy but carry no AGM.

Also worth considering

Best Asparagus Varieties for Scotland → compares all named asparagus varieties head-to-head, with the practical detail that doesn't fit in a summary card.

Care

Water new plants regularly through their first summer; once established, asparagus is drought tolerant and only needs watering in long dry spells. In most soils, established plants crop reliably without extra feeding, especially where the bed is mulchedA layer of material spread over the soil around plants to suppress weeds, retain moisture, and improve soil structure as it breaks down. Full definition → with organic matter each year. Apply a thick mulch every late winter to suppress weeds and hold moisture. Hand-weed rather than hoeing, since the roots sit shallow and are easily damaged, and remove any seedlings from female or mixed plants before they compete with the crowns you want cropping.

Support the tall, ferny summer growth with stakes and twine either side of the row, forming a kind of fence, or with netting about 50cm above the ground, so wind doesn't rock the crowns loose.

Harvesting

Cut spears with a sharp knife about 2.5cm below the soil surface once they reach finger thickness and no more than 18cm tall. There is no harvest in the first two years; from the third spring, harvest for six weeks from mid-April; from the fourth year onwards, harvest for eight weeks. In warm weather, cut every two to three days for the best-quality spears, and expect around 10 spears per plant over the season. Stop cutting by mid-June (Gardener's World), not when spears stop appearing, so the plant can rebuild its reserves: cutting too much, for too long, costs you next year's crop.

Common problems

• Slugs and snails target young spears and seedlings.
• Asparagus beetle adults and larvae feed on stems and foliage from late spring onwards, and can weaken plants badly if left unchecked. Destroy old stems at the end of the year.
• Frost damage is particularly harmful to tender new spring growth, so a sheltered site matters.

Common questions

Sources