Planting an asparagus bed may well be the smartest thing you do this year, right up there with regular flossing and wearing sunscreen. Think about it: how many things can you plant in your vegetable garden that will allow for harvests over 20 years or more? To be smart, however, you must be smart in how you start your bed. This photo tutorial will help you reap bountiful harvests for many years to come.
Site selection and preparation: Choose a site with good drainage and full sun. The tall ferns of asparagus may shade other plants, so plan accordingly. Prepare the bed as early as possible and enrich it with additions of manure, compost, bone or blood meal, leaf mold, wood ashes, or a combination of several of these. Gardeners with heavy soils should consider double-digging their soil. To double-dig, remove the top foot of soil from the planting area. Then, with a spading fork or spade, break up the subsoil by pushing the tool into the next 10 to 12 inches of soil and rocking it back and forth. Do this every 6 inches or so. Double digging is ideal for the trench method of planting asparagus since a 12-inch-deep trench is usually dug anyway. The extra work of breaking up the subsoil will be well worth the effort, especially in heavy soil. The trench is dug 12 to 18 inches wide, with 2 to 3 feet between trenches. The same method may be used in wide-bed plantings, with plants staggered in three rows. Mix the topsoil that has been removed with organic matter. Spread about 2 inches of the mixture in the bottom of the trench or bed.
Which crowns to plant and buy: Choose rust-resistant varieties like “Mary Washington” and the “Jersey” varieties. Crowns should be of a grayish-brown color, plump and healthy-looking. Remove any rotted roots before planting.
Planting: Set the plants 15 to 18 inches apart, mounding the soil slightly under each plant so that the crown is slightly above the roots. Spread the roots out over the mound of soil and cover the crown with 2 to 3 inches of soil. Firm well. As the plants grow, continue to pull soil over the crowns (about 2 inches every two weeks) until the trench is filled. Water if rainfall is inadequate.
Patience is a virtue: Within weeks, you will see your first asparagus shoots breaking through the soil. They will tempt you with their freshness and greenness, whispering “go ahead…you ordered the crowns, you dug the trench, you hauled the compost, you deserve to eat me right now”. Resist the temptation completely in year one and as much as your will power allows in year two. Asparagus is a fern that needs to grow out and capture all the sun it possibly can its first two years to store up energy and build its root system for future production. The more time you give your plants to establish themselves in the first 2-3 years, the longer and heavier they will bear.