Growing asparagus is a long-term investment. It takes several years to produce a good harvest and the plants can use up significant space in the vegetable patch. However, once established they will provide at least 20 years of rewarding succulent fronds.
Asparagus once had a reputation of being difficult to cultivate, but several modern, high yield, cultivars are now available, providing much easier results.
Soil Type: Deep, weed-free, well-drained but moisture-retentive soil, with a pH above 6.5.
Conditions: Full sun.
Ease of Cultivation: Moderate.
Type: Stem Vegetable.
Hardiness: Hardy in most regions of the UK.
Harvest Season: Mid-May to end June
Soil should be deeply dug and enriched with organic matter.
Not suitable for heavy clay soils. It can succeed on heavier soils if they have been deeply cultivated with plenty of humus, plus grit or sharp sand. Although, the best option in this situation is to grow in a raised bed.
Plants can be started from seed but it is much quicker and easier to buy dormant root crowns in spring.
One-year-old crowns can be planted in April, around 2ft (60cm) apart. Plant in a sunny aspect on land with good drainage and protected from strong winds.
Asparagus was traditionally grown on a mounded bed but these days a simple raised bed is just as effective. Dig a 1ft (30cm) deep trench slightly mounded in the centre so the roots slope downwards to the sides. Cover the crowns with finely sieved soil to about 2in (5cm) and fill to the surface as the plants grows.
The roots can forage down as deep as 4ft (1.2m)
so a generous depth of soil is essential.
Water young plants until well established, after which, water only when necessary.
In the spring, cover the young shoots with horticultural fleece if a late frost is forecast.
Keep the bed weed-free. Do not hoe too deep and only hand-weed in raise beds. Do not raise any other crops between plants.
Mulch with well rotted manure or alternative in January. In the spring, apply a balanced fertilizer like fish, blood and bone or Growmore.
Cut down the yellowing foliage in the autumn to about 4in (10cm) above ground level.
Susceptible to attack by Asparagus beetle and slugs. Asparagus beetles are small with orange markings on their long bodies. They can attack both foliage and spears. Remove them by hand or spray with an appropriate insecticide suitable for vegetables.
Rust disease can be a problem in very wet years. Remove any infected shoots.
The main problem growing asparagus is over-cropping in the early years, which causes weakened plants and spindly spears. Show restraint when the plants are developing by not harvesting a crop in the first two years, thus allowing the plants to build up a good strong root system.
Harvest from mid-May to the end June. Then stop cutting to allow the spears to develop and put energy back into the crowns for the following year's crop.
Harvest when she shoots are about 8in (20cm) tall. Cut just below soil level with a sharp knife. Harvest spears up until the middle of June. After which, allow the plants to rest and built up for next season.
Asparagus has a very short storage life and should ideally be eaten as soon as its picked.
Cut off the woody parts from the base of the stems. Wash and cook in boiling salted water for 10-15 minutes.
Low in calories and packed with essential vitamins, minerals and antioxidants, asparagus is high in fibre, vitamin C, A, K, E, folate, potassium and phosphorous.
Male asparagus varieties now dominate the market. They are more productive, diverting energy into edible spears rather than seeds and berries.
Asparagus 'Burgundine' is a new sweet crunchy variety with low fibrous lignin, allowing it to be enjoyed raw or lightly steamed. Perfect for main season growing. Available at Thompson & Morgan.
Asparagus 'Guelph Millennium' is a robust all male form producing good reliable yields, even in cold regions. Available from You Garden.
Asparagus 'Gijnlim' is a reliable early cropping variety that produces succulent green spears with dark purple tips. Suitable for both white and green asparagus production. Available at Thompson & Morgan.
Asparagus officinalis 'Ariane' is a vigorous male variety with thick, succulent, purple tipped spears. Easily grown from seed - cropping in just three years. Height to 18in (45cm), spread to 10in (25cm). Seeds available from Van Meuwen.
Asparagus officinalis 'Guelph Millennium' a cold tolerant variety, well suited to UK weather conditions. Produces high yields of late season, purple-tipped, green spears. Available at Thompson & Morgan.
Asparagus officinalis 'Mondeo' is suitable for both spring and autumn planting. A vigorous grower with high yields, it is a good early season variety. Excellent disease resistance. Height to 5ft (150cm), spread to 18in (45cm). Available at Thompson & Morgan.
Asparagus 'Vittorio' produces thick, straight spears of superb quality. Developed primarily as a white asparagus, where the spears can be 'earthed up' to produce a tender, white appearance. Available at Thompson & Morgan.