Jun 012017
 

Asparagus are a hardy perennial vegetable that is highly versatile in the kitchen. They are great on the bbq and fantastic in stir frys. Asparagus are best grown from crowns in winter as they are guaranteed to be male plants, which are generally thicker and higher yielding than females. They can also be purchased and planted from seed-grown stock at any other time of the year, however there is no guarantee the plants will be male.

Preparation and Planting

Asparagus are quite easily grown and when established, will continue to produce for 15-20 years. A sunny position, preferably free from strong winds and potential competition from trees should be chosen for the permanent placing of the plants. Asparagus adapts well to most soils with good drainage, but for permanent plantings, they do best in a deeply dug,
friable soil to which has been added liberal quantities of organic matter. Ideally, the bed should be raised and of an
area large enough to allow the asparagus crowns to be planted 40 cm apart. To two – thirds soil, add one – third of
compost and cow manure and mix through the soil. Choose a site that will be disturbed as little as possible for at least two years… asparagus hate being poked and prodded.

Dig a trench 30 cm wide by 20cm deep, making a mounded ridge in the bottom of the trench. Place the asparagus
crowns on the ridge, spreading the roots out down either side. Back fill the soil until around 5 cm of soil covers the
roots leaving the crown at the soil surface. Water in well and mulch.

Harvesting

Do not cut any of the spears in the first season so as to promote a vigorous, healthy and long-lasting root system.
Simply let the asparagus grow, (the fine leaf growth is called a fern). Prune the fern back to the ground in winter.
In the second year, about 30-50 per cent of the spears can be cut. In following years, about 80 per cent of the
spears can be cut. Spears can be cut over a period of about 10 weeks from the time they first appear in early
spring. Growth can be rapid and it may be necessary to cut every 2-3 days. Green spears can be cut from flat beds
when 15-20 cm long and before the tips start to open. For white asparagus, soil should be raised up to about 20cm
over the row in late winter. White spears are harvested by pushing a knife into the soil and cutting the spears 15cm
below. When the harvesting season has finished, then let the fern grow.

Ongoing Care

Leave the fern to grow on until it turns yellow in winter and then cut it off at ground level. Soil which has been raised up can then be levelled, cultivated and re-fertilised in preparation for raising up again in late winter before the new season’s crop begins. It is a good idea to top up Asparagus beds with manure each winter. Keep asparagus well watered in summer, and weed free year round. Maintaining a good layer of mulch will help you achieve both of these.

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