Asparagus

The Care and Cultivation of Asparagus Crowns

Asparagus is quite easily grown and when established, will continue to produce for 15-20 years.

Position

A sunny position, preferably free from strong winds and potential competition from trees should be chosen for the permanent placing of the plants.

Preparation and Planting

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.

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.

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 ‘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.

On-going 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-fertilized 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.

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