Guide to Growing Asparagus
Guide to Growing Asparagus
Asparagus – Asparagus offcinalis var. altilis
This is usually regarded as a luxury crop which makes many gardeners shy of growing it. The wild species, Asparagus officinale, can sometimes be found but it is the cultivated forms of this species that are grown in gardens.
Cultivation is not difficult, but preparation of the site should be thorough, since it is usually possible to cut regularly from the same bed over a period of twenty years or more. For preference, choose a sunny situation sheltered from biting winds and move thedeeply, taking out all perennial .
The plants do best in rather light, sandy soil laced withalthough they can be grown quite successfully in heavy clay ground, providing there is good drainage. Sandy loams are best since they warm up quickly in spring and encourage the crowns into early growth. The prepared beds should be given a 13 mm. Thick mulch of well rotted manure or rich , and the crowns planted in early spring, but so that they can become really established, no cutting should be done the first season after planting.
When planting the crowns, take out trenches about 30cm deep, making mounds of fine soil in the centre. On these, set the octopus-like roots 45cm apart. Then firmly work the soil between the roots finishing off with a depression to hold water should the summer be dry. The top of the crowns should be 12 to 15cm below soil level. On sandy, well drained soil, the crowns may be planted on the flat. When hoeing between the rows never go deeper than 5cm otherwise the shoots may be damaged.
Although not essential, a dressing of agricultural salt 2oz to the square metre applied in spring will be beneficial. It is best not to cut the first year after planting and then not to take more than two or three spears from each plant, leaving the thinner ones to mature into, which will help to ensure larger crops the following season. Cut the succulent shoots when they are about 10cm high, severing them well below soil level, using a special asparagus knife or something similar. On very sandy soil the shoots can be snapped off.
The foliage which is left to develop should be cut down to within 15cm of soil level when it becomes discoloured. Do not let any berries that form fall to the ground, otherwise uselessmay appear which subsequently become difficult to eradicate. This action will help to destroy the eggs of the only likely pest, the asparagus beetle, which may bore into the crowns that are left to develop, causing them to become brown. If the beetle is suspected spray the plants with Derris or Pyrethrum.
Asparagus can be forced in frames where a hot bed has been made. They can also be grown in boxes of not more than 30cm deep. Place a little good soil in the bottom, pack the roots closely together on this, and just cover them with ordinary soil. Moisten occasionally with tepid water, and stand in a temperature of 15 to 20°C. Forcing can begin as soon as roots can be obtained from the open ground.
Roots or crowns for forcing purposes must not be less than three years old and a supply for this purpose should be grown in flat beds. Where there are low forcing houses with side beds and hot water beneath, all that is necessary is to pack the crowns closely together on the bed. Cover them with the soil and mats till growth begins.
Success in growing good asparagus, comes from planting top quality crowns, making up the bed correctly, and giving the plants ample room.
The soil should be prepared early and enriched with old manure and plenty of compost. Sedge peat worked into the top couple of inches of soil will be helpful. Sow seed in early spring using pots or boxes of sandy soil in a temperature of 15°C.
When growing this vegetable, it is important to make sure that the drainage is really good, and except on light land it is advisable to raise the beds a foot above the surrounding soil level. The ground should be deeply dug and be given a good dressing of well-rotted manure. The planting season is April, and the plants should be placed 15in. apart with 18in. between the rows. Set the corms 2 to 3in. deep. Beds 4ft. wide accommodating three rows are most convenient. One-year-old plants are best, but no shoots should be cut until the third year after planting. During the first year allow the plants to grow and give them a little fertiliser. In the second year pull up a little soil along each side of the row, as though one was earthing-up, doing this at any time before growth starts. Feed at least twice a year at this stage and then start to cut in the, third year. Ample supplies of water must be given during dry weather.
After cutting down the growth, about the first week in November, a dressing of well-decayed manure should be applied. Cutting should never be continued beyond mid-June, and sufficient growth must also be allowed to remain to keep the plants growing strongly. Increase by sowing seed in light soil in rows 1in. deep in early April. Thin the resulting seedlings to a foot apart and plant in their permanent quarters the following April.
Reliable varieties include: Argenteuil, a variety of French origin; Connover’s Colossal, the most popular sort with fine pointed buds; Kidner’s Strain, highly recommended; Mary Washington and Martha Washington two American rust resistant varieties, but not so heavy cropping; White Cap, a high quality variety with pale green, almost white buds; and Giant French, a comparatively new variety of outstanding quality.