RESPONSE OF SPRING-HARVESTED AND SUMMER-HARVESTED ASPARAGUS TO HARVEST PRESSURES

The objective of this study was to determine the effect of cutting pressures on fern and crown growth of spring- and summer-harvested asparagus (Asparagus officinalis). Two-year-old 'UC 157 F1' asparagus seedlings, grown outdoors in 57-liter pots, were harvested for the first time in spring (Mar. 1988) or summer (July 1988) at cutting pressures of three, six, nine, or 12 spears/plant. Fern was mowed to encourage spear emergence in summer. Cutting pressures had no effect on spear diameter in either season. Summer harvesting required 52% less time to complete than spring harvesting. Fern of spring-harvested plants lived 63 days longer than fern emerging after summer harvests; cutting pressure had no effect on fern lifespan. By Nov. 1988, crown quality and growth, harvest times, and storage root carbohydrates were similar among all cutting pressures; however, carbohydrate content was higher in summer-harvested than spring-harvested crowns. Crowns were cold-stored during Winter 1988 and planted in the field in Spring 1989. Plants harvested in Summer 1988 produced 21% more fern in Summer 1989 than those harvested in Spring 1988. Fern production in 1989 was similar for all cutting pressures.