Growing asparagus

Asparagus  - asparagus officinalis

Asparagus is arguably the queen of vegetables. This is partly because of its fairly short season, particularly in the UK, its exquisite delicate flavour, the perception that it is tricky to grow and its undoubted high cost in shops.

One of the downsides of eating asparagus is the nasty smell experienced by many [though not all people who eat it]. It has long been believed that asparagus changes the smell of our urine, giving it a stench reminiscent of bad drains. However, on discussing this with a plant scientist recently who had done some work on this subject, she assured me that asparagus does not, in fact, alter the odour of our urine but, actually affects our sense of smell though, not in all subjects.

Sowing and Growing

Growing asparagus can be tricky but it is worth the effort even if your plot is less than ideal.

Although it is possible to grow asparagus from seed and it is certainly cheaper to do so, it does add another year to an already impatient wait until harvesting. Although I haven’t tried this method, if you would like to try it I recommend Nicky’s Nursery [www.nickys-nursery.co.uk] as being a reliable source of an excellent range of seeds, including organic and Heritage varieties.

Although I do love large garden centres - they inspire me, encourage me to spend money, keep me up-to-date with new products and developments in gardening and plants - they really are the last place to buy asparagus crowns. They come in polythene packets with very pretty and tempting illustrations, in a bed of very desiccated peat, where they have probably been hanging for some weeks, if not months. Each packet will probably contain 2 – 3 crowns where an odd shoot or two might just be visible to indicate a small sign of life. The chances of these crowns surviving is very touch-and-go and do need perfect conditions to establish.

Do buy your crowns from a reputable provider. It is usual to buy one-year-old or two-year-old crowns but some of the seed houses will supply three-year-old crowns which can save another year of waiting until harvesting. [though it is felt that younger crowns establish better.]

To plant – create a large raised bed [within a framework or not].

The crowns will need a well drained [sandy soil] and fertile site in a sunny situation. You must consider the site you have, which may not be suitable for growing asparagus. I grow in a very heavy clay soil yet, can still achieve an excellent asparagus crop for my own uses and to share with my friends. Create a good asparagus bed – for a bed for 10 crowns – think of an area of 3metres x 1.5 metres allowing for a staggered planting. I find it best to create a bed on a level with the surrounding ground then add loads of well rotted manure and compost [garden compost or bought-in] to a fairly high level several months before planting my crowns.  A wooden framework for this purpose is useful but, is not essential. Consider also that this bed will be more-or-less permanent as you can expect to harvest from these plants for around 20 years once they are well established.

Dig this out to allow for planting the crowns 20cms [8in] and the growing tips covered by 4 – 5 cm [2 inches] of fine soil or compost. Spread out the spider-like roots around the area and cover with compost or well-worked soil to give a good covering and growing environment. If the new plants are already putting up new shoots, you can allow them to appear above ground. The finished bed should be several inches – 6 – 8 [15 centimetres] above the surrounding ground. It is important to keep this area well weeded over the coming seasons.

If you are lucky enough to be growing on a light, sandy, well drained soil, it is not essential to create a raised bed, or even advisable as the beds could become too dry.

Water the bed well in dry weather.

The ferns can grow to a height of 1 metre and can be susceptible to wind rock, so support will be necessary. Keep the beds well weeded [don’t use a hoe]. As the ferns turn yellow in autumn they can be cut off leaving the bottoms of the stems a few centimetres above ground. Remove any debris, weeds or leaf litter and mulch the bed well to protect the crown during the winter.

Types and Varieties

Asparagus is a spring to early summer crop and the varieties you choose will dictate the when you will harvest. Some providers will offer a variety which can extend your harvesting period. It is thought that male plants are superior as they can live longer and the plants are not weakened by the production of seeds and many providers will claim that the crowns they are selling are male only. However, the seeds can be removed from the ferns as they develop and the female plants often produce thicker spears.

Connover’s Colossal is an old favourite which is still available but, there are many new varieties now available. The new purple varieties are considered to be sweeter and more tender than the green varieties and are delicious raw in salads [the sellers claim] but, do check what is available from the seed houses before you buy. For a good range of products try Thompson and Morgan – www.thompson-morgan.com, Marshalls – www.marshalls-seeds.co.uk, Suttons seeds – www.suttons.co.uk  , Dobies seeds – www.dobies.co.uk 

Harvesting and Storing

Asparagus should not be harvested for two to three years after planting [depending on the age of the crowns you buy] – the ferny tops should be allowed to grow to ensure the roots are well fed for the following year.

You can start to harvest – using a sharp knife, cut the stems below the level of the soil once the spears are 5 – 6in [12 – 15cm] high – from April into early June [depending on the variety.] You must stop harvesting by mid June to allow the next spears to grow to their ferny maturity which will build up the plants for subsequent year’s crops.

Asparagus should be cooked as fresh as possible but will keep in a fridge, in a polythene bag for up to three days.

To freeze – clean the spears well, cut off the tough ends. Sort the spears into small bundles depending on the thickness of the stems. Blanch them for 2 to 3 minutes, drain, cool and pack into suitable containers to freeze.

Nutritional Value

Excellent source of	Useful amounts	Traces
Vitamin C Vitamin K	Fibre Vitamin A Vitamin E Folate	Fat, Protein [incomplete] Niacin, Thiamin and B6 Calcium, Iron, Magnesium, Phosphorus, Zinc Potassium, Copper, Manganese, Selenium

Pests and Diseases

Pigeons – will eat the young growth from any young plants on our plots when nothing else is available. They will eat their way through the young spears as they appear above ground.

Slugs and Snails – Although not a serious pest, slugs and snails will eat the tops of the young spears as they appear.

Spindly shoots – if your crowns are having difficulty establishing after planting they may put out spindly, thin spears. Don’t attempt to harvest them. It is possible that, with good management and feeding, the crowns will improve. However, if this continues into a second year, it is probably best to abandon them and start again on a new bed.

If you harvest your spears too soon – before they have become established – you are likely to have spindly growth in the following year. You can try feeding them well and don’t harvest for a couple of years until the spears have become thicker and more plentiful.

If you continue to harvest too long into the season, the crowns will not have the time to develop enough ferny tops to nourish the crowns for the following year. Don’t harvest after early June.

Asparagus Beetle – is probably the worst pest of asparagus especially in the allotment situation where other growers are also dealing with this serious pest. If you are growing in a garden away from any other growers, it is not likely to be troublesome.

The beetles themselves don’t do any harm except to lay the eggs of this very specific plant pest. The larvae, are the main problem and will eat the ferns and the stems resulting in a reduced crop or no crop in the following year.

 

 

Remove the beetles as you see them and crush them along with any larvae you see [I advise wearing fine rubber or nitrile gloves for this purpose as they are unpleasant little pests]. It is a good idea to check every day or at least every time you visit your plot.