Asparagus, Asparagus Officinalis, a hardy perennial from the Liliaceae family. Asparagus is an ancient vegetable highly prized for its wonderful flavour as well as its nutritional and medicinal values, it produces tasty edible spears in mid spring. Asparagus may seem like a lot of work and a long wait to get started but once the plants have settled in and the asparagus bed has started producing it can’t be beaten, it really is worth taking the time and making the space for it.
Asparagus is believed to be a native of the Mediterranean lands but it has been found “wild” in so many places that there is some confusion as to where it actually originated. There are references to asparagus in ancient Egypt, Greece, Syria and Spain. It is known to have been cultivated by the Romans since at least 200 B.C. but it was not until the 16th century that it became popular in France and England. From there the early colonists took it to America.
Site & Soil
Asparagus is best in full sun in an open site but not too exposed to wind. It requires rich, (low nitrogen) well-drained, sandy soil and prefers a PH of between 6.5 – 7.5. Asparagus grows best at 16-24c but needs cool winters during its dormant period to crop well in spring. The natural habitat of Asparagus is maritime and it can be found growing wild in many seaside locations around the world. It thrives in soils that are too saline for many other plants and is an ideal plant for a seaside garden.
Preparation (asparagus trench)
Incorporate a good amount of manure before planting. (preferably in autumn leaving the soil rough until March). In March dig a trench 20cm deep and 30cm wide. If soil was not prepared beforehand incorporate manure and leaf mould. Shape soil at the bottom of the trench into a ridge 10cm high running the entire length of the trench and sprinkle with bone meal. Trials have shown that adding sheep manure, bone or wool to the very bottom of the trench ensures a slow release of nutrients over a long period and will benefit asparagus. We happened to have all of the above from the late sheep that roamed the mountain so they went into my trenches.
- by division – divide roots in late winter or early spring when buds are just developing and before new root growth begins in earnest. Carefully lift crown with a fork. Shake off excess soil. Cut away any damaged or diseased growth from each section. Take great care not to damage or cut into any buds. Pries apart the crown into sections each with at least one good bud. If necessary gently cut through the Crown. Place crowns 60cm (some say 30-45cm) in a single bed or in beds with 2-3 rows 60-90cm apart. Lay crowns upon the prepared ridges spreading the roots down either side. Gently fill in the trench with sifted soil so that : only the buds are visible. Earth up as the asparagus grows to always keep the same amount of stem uncovered. By autumn the trench should be filled In warmer climates cover the bud tips with 5cm of loose soil to stop them drying out.
- by seed – Sow seeds in a seed bed 2.5cm deep and 8cm apart in rows 30cm apart. Transplant the largest as crowns to their permanent position the following spring (see above). Alternatively sow in modules in late winter – early spring (13-16c) and transplant in early summer ready to harvest after 2 years. TIP Soak seeds 2 days before sowing.
An asparagus bed will provide spears for 15-30 years if well maintained so it is worth taking care of your beds. The roots store the energy produced by ferny stems during the growing season. Once harvested Asparagus should be left to grow ferns and be kept weeded, watered and fed so that a fresh crop of spears can be produced next year. Keep asparagus beds weed free and moist. Do not let the beds dry out or get water-logged. After spring harvesting apply a general fertiliser or seaweed based meal to nurture stem growth and build up plants for the following year. In autumn cut down the ferny stems once they have turned yellow (burn to avoid harbouring asparagus beetle eggs). Stumps should be left 3-4cm proud. Apply a heavy top-dressing of well-rotted manure in Autumn to late winter or cover beds in seaweed. Remove in spring if the seaweed has not rotted down. Feed again with fish meal, chicken dung, seaweed and add a sprinkling of salt in Spring.
It will normally take 3 years to crop from seed, but crowns can be bought at 1 or 2 years old which will crop in 1-2 years. Asparagus is ready to harvest once the spears reach 10-17cm long. Cut them obliquely about 2.5-5cm below the surface with a sharp knife or serrated asparagus blade. Harvest period is 6- 8weeks but do not harvest after midsummer as this will result in weaker spears next year. Our Asparagus season starts with the first spears in the first week of April and continues through to mid May at which point I stop cutting the spears to allow the plants time to grow a last flush of spears that will turn into ferns.
Storage & Culinary
Asparagus is such a delicious vegetable that when it arrives you just want to eat it as fresh as possible. It is said that the water should be put on to boil before cutting the asparagus, so that the fresh spears can be dropped straight into the boiling water. Asparagus is also delicious stir fried, grilled over hot coals, in salads or made into a light soup. In ancient times asparagus was dried to be eaten over the winter nowadays we can freeze it.
Asparagus is a wonder plant nutritionally. It is high in Folic Acid and is a good source of potassium, fiber, vitamin B6, vitamins A and C, and thiamin. It is the best vegetable provider of folic acid, necessary for blood cell formation and growth, as well as liver disease prevention. Asparagus has no Fat, contains no Cholesterol, is low in Sodium and is low in calories, each spear contains less than 4.
Asparagus grows well with Tomatoes, Parsley and Basil. I have found that growing New Zealand Spinach between the raised beds works well by allowing it to creep over the beds it helps retain moisture in the beds during the hot summer months. The light shade cast by asparagus ferns in the summer months could also be used to benefit other plants such as lettuces and spinach which struggle in the heat.
MDD Growing log
When we arrived at Mas du Diable in early winter I discovered a few straggly asparagus ferns growing in the orchard. I thought they were wild asparagus but it turned out these plants were the remains of an asparagus bed that had been planted around 15 years before. After resuscitating the old crowns we still needed more so the plan is to grow the rest from seed and aim for a bed of at least 30 crowns.
2004 In spring I dug the asparagus up just as the buds were emerging, dividing it carefully into 10 crowns and started our first asparagus bed in the veg patch. I left all the spears without cutting to turn into ferns. By autumn the ferns looked healthier than they had, abandoned in the orchard, but definitely needed beefing up. The beds were top dressed with seaweed meal and compost.
2005 Each of the found crowns produced perhaps 5 or sow thin spears which we cut to eat until the beginning of June then left the plant to grow ferns. The ferns looked big and strong and an improvement on the previous year.
2006 We sowed Jersey Knight Improved (10 seeds from T&M) individually in pots in a heated propagator in January, 6 germinated. I set out the plants in a protected seed-bed, uncovered cold frame, in April where they grew well. Meanwhile the found crowns provided a decent harvest and have produced huge ferns which I hope means a better still crop next year.
2007 I have another more generous packed of Argenteuil (350 seeds from Franchi) to try which i plan to sow 1/4 in January and then again in March as the seed packet recommends March to the end of June.
2008 The beds are now well established and produce a good crop sometimes as early as February and I always follow the rule of not cutting beyond the summer solstice.