Variety Options

Only hybrids that are tolerant to Fusarium crown or root rot should be grown. The varieties listed here are tolerant to Fusarium and to rust. The “Jersey” series are generally all-male hybrids. (Older varieties were half male and half female plants.) Male plants do not expend energy producing seed and are more vigorous than female plants. Also, the lack of seed precludes the growth of nuisance seedlings which are not productive and act as weeds.

Jersey Giant*
Jersey Supreme
Jersey King
Jersey Knight
Milenium

* Some plants are female.

Lime

Apply lime to maintain soil pH at 6.8 to 7.0 This may require yearly applications of lime. Asparagus does not tolerate acid soils! For new beds, deeply incorporate lime to insure proper pH at crown depth. This should be done the year before planting.

Fertilizer

Less nitrogen fertilizer will be needed if manure or legume sod was plowed down (see Nitrogen Credits pages 6-9).

For new asparagus beds, phosphorus fertilizer should be applied to the bottom of the furrow at planting time. If phosphorus is placed on the surface, there will be little if any downward movement into the root zone. This is the last opportunity to place phosphorus in the root zone.

Spacing and Planting

Crowns: Plant healthy one-year-old crowns in furrows about 6 to 8” deep. Be sure the bud is facing up and roots are spread out. Space crowns 12” apart in rows 54” to 60” apart. Closer spacing produces higher yields in early years, but thinner spears in older beds. This will require 8,712 to 9,680 crowns per acre or 100 crowns per 100 feet of row. This spacing is for hybrids and is somewhat greater than was recommended for less vigorous nonhybrids. Closer spacing may produce higher total yields but usually results in thinner spears. Cover with 2” of soil.

Transplants: Fields can also be planted with eight- to 12-week-old asparagus seedlings after the danger of frost has passed. Plant spacing is the same as for crowns. Care must be taken in order to prevent the small young ferns from being smothered by soil especially after heavy spring showers. Start transplants in containers or cells that are 2” or larger. Use a sterilized medium consisting of half sand and half peat or use a commercial seed starting mix. Seed germination will take at least three weeks and the soil must be kept uniformly moist during this time. Young seedlings should be fed with quarter- or half-strength soluble fertilizer solution once each week or as needed. The nitrogen in this fertilizer should be in the nitrate form because young seedlings are sensitive to ammonium sources of nitrogen.

Care of Young Beds

It is essential to maintain healthy fern growth during the first two growing seasons. Weed control during the first season is easily accomplished by slowly filling in the trenches during the season. These cultivations can be timed with flushes of weeds. Be sure ferns are not covered. During the second year the beds must be kept weed free, especially during late summer and fall. Weed competition late in the season will restrict crown growth. Close attention must be given to insects and diseases that attack young ferns. As ferns become vigorous and full, diseases can cause the ferns to die prematurely, especially in late summer and early fall during periods of humid weather. Fungicides should be applied to control this foliage decline.

Harvest

Spears may be harvested two to three times at the beginning of the third season. The harvest period should not exceed two weeks. The harvest season is increased one to two weeks each year but should not exceed six weeks. Length of harvest season is determined by bed vigor. If spears are predominantly small in diameter, harvest should be stopped. Overcutting causes rapid decline in bed vigor. Spears can be snapped or cut at or below the soil surface. Avoid injury to newly emerging spears.

Once spears have been bunched and trimmed, they should be placed upright in shallow trays of water and kept cool. Ideally they should be refrigerated at 32°F in order to maintain sugar content and tenderness.

Fern or Brush Removal

Mow and disc brush in early spring before spear emergence. Use shallow discing, no deeper than 2” to 3” in order to prevent crown injury. Beds can also be disced after harvest to control weeds prior to herbicide application.