Cultivo del Esparrago

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From: http://pakagri.blogspot.com.es/2012/08/growing-asparagus.html?goback=.gde_1133637_member_142494579

Plant once, harvest for years: A well-maintained bed of this sweet, slender veggie will stay productive for up to 15 years, and, with its vibrant, ferny foliage, asparagus makes an excellent ornamental. 

Gardeners have been growing asparagus (Asparagus officinalis) for more than 2,000 years, and this sweet, slender veggie’s staying power is no surprise: A well-maintained asparagus bed will start bearing one year after planting and will stay productive for 10 to 15 years.

A hardy perennial adapted in Zones 3 to 8, asparagus grows best in well-drained soil with a near-neutral pH between 6.5 and 7.5. The edible part of the asparagus plant is the young stem shoot, which emerges as soil temperatures rise above 50 degrees Fahrenheit in spring.

Types to Try

Because asparagus stays productive for so long, it’s important to plant the best variety available for your area. In cold climates, ‘Guelph Millennium’ and other varieties that emerge late often escape damage from spring freezes. In warm climates, early, heat-tolerant varieties such as ‘Apollo’ and ‘UC-157’ produce well before the weather turns hot. Gardeners in Zones 4 to 6 have a wider selection of varieties, including ‘Jersey Giant,’ ‘Jersey Knight’ and other hybrids bred in New Jersey for improved disease resistance and better productivity.

When to Plant

Plant asparagus crowns (dormant roots of 1-year-old plants) in spring at about the same time you would plant potatoes, but don’t rush to plant them if your soil is still cold. A few varieties, such as open-pollinated ‘Purple Passion’ and hybrid ‘Sweet Purple,’ can be grown from seed. Start seeds indoors in spring and set out the seedlings when they are 12 to 14 weeks old, just after your last spring frost. Start with asparagus crowns, however, to eliminate the year of tedious weeding that comes with starting from seed.

How to Plant

Choose a site with fertile soil that’s clear of perennial weeds and grasses. A single row of asparagus plants set 15 inches apart will fill in to form a 24- inch-wide bed, or you can grow a double row in a 36-inch-wide bed. Locate asparagus along the back or side of your garden, as 5-foot-tall asparagus fronds will shade any nearby plants. A bed of 25 mature plants will produce about 10 pounds of asparagus per year.

Asparagus craves phosphorus, which is usually abundant in composted manure and in compost made from kitchen waste. Add a 2-inch layer of rich, weed-free compost to your soil before planting. Dig a trench 4 inches deep and 10 inches wide in the amended soil and arrange the crowns in the bottom, about 15 inches apart. Refill the trench without stepping on the bed.

Maintaining Your Bed

Controlling weeds during the first two seasons will require rigorous weeding by hand. Pull out weeds early and often, and mulch with hay, grass clippings or another organic material to suppress weeds and maintain moisture. Weeds will become less of an issue as the plants fill in.

In early winter, after several hard freezes have damaged your asparagus fronds, cut them off and compost them to interrupt the life cycles of insects and diseases. Fertilize the bed with a 1-inch layer of rich, weed-free compost or manure topped with 3 inches of straw, rotted sawdust or another weed-free mulch. Clean spears will push up through the mulch in spring. Fertilize your asparagus again in early summer after you’ve stopped harvesting spears. You can top-dress with a balanced organic fertilizer, or scatter another inch of rich, weed-free compost over the decomposing mulch.

Harvesting and Storage

The exact dates of your spring picking season can vary by two weeks or more because of variations in soil temperature from year to year. Snap off spears longer than 4 inches at the soil line as soon as they appear in spring. As long as a new planting grew vigorously its first season (and your growing season is not extremely short), you can harvest spears for two weeks after your planting is a year old.

The next season, harvest all spears that appear for the first four weeks of active growth. In your third season you can harvest asparagus for six weeks, and by the fourth year the plants will be strong enough to tolerate a full eight-week harvest season.

Promptly refrigerate your harvested asparagus. You can pickle, dry, or blanch and then freeze bumper crops.

Growing Tips and Ideas

Get Psyched for Your Spears. Prepare your bed when you order your asparagus crowns so you can plant them as soon as they arrive.

Choose Male Plants. Most hybrid asparagus varieties are able to produce seven or more spears per mature plant because they are male plants that don’t expend energy producing seeds. However, if you’re growing open-pollinated or hybrid varieties that do include seed-producing female plants, dig out female plants to limit reseeding. Asparagus seedlings are difficult to pull and may become bothersome weeds in some climates.

Tuck Them In. Freezing temperatures ruin asparagus spears, so harvest yours before any harsh spring weather. During the first weeks of the harvest season, covering beds with row cover tunnels held aloft with hoops can help limit damage from the cold.

An Edible Aesthetic. Ferny fronds of asparagus are a beautiful addition to edible landscaping beds, and asparagus stems make great filler material in flower arrangements.

Outsmart Asparagus Beetles

Two species of asparagus beetles damage spears and fronds throughout North America: the common asparagus beetle (black, white and red-orange) and the spotted asparagus beetle (red-orange with black spots), which are both about a third of an inch long.

Asparagus beetles overwinter in plant debris, so removing fronds in winter will reduce their numbers. Lady beetles and several small wasps are major asparagus beetle predators.

Handpick adult asparagus beetles early in the morning when it’s too cool for them to fly. Asparagus beetle eggs look like stubby, brown hairs. Wipe them off of spears with a damp cloth. After they’ve begun feeding on fronds, asparagus beetle larvae (soft, gray, slug-like creatures with black heads) are unable to crawl back up plants if swept off with a broom. Many gardeners allow their poultry to clean up the asparagus bed for three to five days at the end of the harvest season to rid the plot of overwintering adults.

If you have an asparagus beetle problem but don’t have poultry, set aside a section of your asparagus to serve as a spring trap crop. Don’t cut the spears in spring within the plot, but patrol often to collect as many asparagus beetles as you can. In late summer, cut the fronds 2 inches from the ground and compost them. In three weeks or so, you can harvest a fall crop of spears from your trap crop plot.

In the Kitchen

Delicate spears of asparagus are welcome at every meal. For breakfast, asparagus pairs beautifully with bacon, eggs, ham or melon. Layer lightly steamed spears onto lunch sandwiches, or incorporate them into pasta salads, quiches or bread puddings. Asparagus risotto can round out dinner, or you can serve asparagus roasted, braised or grilled as a side dish.

Asparagus cooks quickly. Toss spears with olive oil, salt and pepper, and then grill for just two to three minutes. You can make roasted asparagus by cooking oiled and seasoned spears in an open pan in an oven at 450 degrees Fahrenheit for eight to 10 minutes.

Asparagus is an excellent source of folacin, a B vitamin that helps keep the circulatory system strong, and it’s a good source of potassium and vitamin C. Claims that asparagus fights cancer are based on its high level of glutathione, a potent antioxidant. Light cooking (such as steaming) for eight to 10 minutes increases the bioavailability of asparagus’ healthful compounds.

Asparagus has long been considered the ultimate gourmet vegetable, thanks to its delicious taste and delicate texture. Follow our guide to growing your own supply of fresh seasonal spears

About asparagus

Asparagus is a perennial vegetable, which makes it good for growing on plots where it will not be disturbed. However, it does take a long time to grow to maturity, so make sure you are planning to stay a while to see the fruits of your labour.

For a decent crop, asparagus needs to be given lots of space and is ideal for a large garden or allotment. It thrives in sun and well-drained soil, but needs some protection from the wind. Alternatively, grow in a raised bed. Asparagus is not suitable for containers, and will sulk if planted in heavy clay soils or in a shady spot.

What to do

Soil preparation

• Asparagus plants can remain productive for up to 20 years, so it's worthwhile spending time on preparing the bed to give them a flying start in life.
• If you can, start in autumn by digging over thoroughly, mixing in plenty of well-rotted farmyard manure, and removing all perennial weeds.
• A week or so before planting, scatter some general fertilizer granules over the area (about 90g/sq m is ideal) and fork in, before raking the ground level.

How to plant

• You will need about an hour to plant 10 crowns. Make a straight trench, 30cm wide by 20cm deep, and then pour soil down the length of the trench to make a 10cm high mound.
• Next, carefully take your asparagus crowns and sit them on top of the mound, spreading the roots out either sides - plant crowns 30cm apart and then cover with about 5cm of soil, which has been sifted through a riddle or sieve.
• Cover the plants with more sifted soil as the stems grow, aiming to completely fill the trench by autumn. Subsequent rows should be spaced 30cm apart.

aftercare

• Water newly planted crowns thoroughly and keep damp during dry weather. Succulent spears may appear soon after planting, but avoid the temptation to harvest them or you'll weaken the crowns.
• During their first two years of growth, plants should be left to form lots of ferny foliage - cut down the stems in autumn, leaving 5cm stumps above the ground.
• To prevent competition, keep beds free of weeds.

Harvesting

• Most plants are ready to be picked two years after planting, although several modern varieties have been bred for earlier cropping.
• To harvest spears, wait until they're about 12cm long and remove them with a serrated knife, cutting them off 7cm beneath the soil.
• Stop harvesting in mid-June to allow the plant to build up its energy for next year, and give plants an extra boost by feeding with a general fertilizer

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