Get the best from asparagus
QHaving taken on a new allotment, we were surprised and delighted to find an established asparagus bed. How should we maintain it?
AThis perennial veg is long-lived, and if it is well-cared for it should deliver tasty spears for years to come. Most of us have had to order our dormant crowns and prepare a well-drained, sunny bed by digging in or spreading lots of well-rotted garden compost.
Arriving in spring, the crowns are planted immediately, usually by the traditional method of digging trenches and making ridges along them. The crowns are sat on the ridges, so their fleshy roots can drape outwards and downwards with no breaking or coiling. The aim is to have them 15in (38cm) apart in rows 20in (50cm) apart, with growth buds just at the surface.
My first attempt at starting both an asparagus bed and a row of raspberries here was a disaster, because we sited them on the lower half of our kitchen garden. We now know the heavy soil stays wet in winter, and both crops succumbed to waterlogged soil. However, a second planting of both on higher ground went on to thrive. There is then a wait of two years while plants become established, before the first light cut of spears is taken.
To maintain mature asparagus, winkle out any weeds before they need digging out – an action that would break or disturb the asparagus roots. In late winter or early spring, apply a dressing of general-purpose fertiliser, followed by a mulch of well-rotted compost over the roots, then wait for the spears to rise.
At peak production, you could be cutting every other day. If spears are weak or slow, feed again after harvesting to encourage a good growth of fern. After a final weeding in autumn, spread a mulch of well-rotted compost and allow the fern to die back before cutting.