Response of broccoli (Brassica oleracea var. italica) yield and hollow stem to plant density, trickle irrigation and transplanting date

Abstract

Maximizing yield and quality of processing broccoli (Brassica oleracea L. var. italica) is critical to successful production in Atlantic Canada. Field studies were conducted from 2004 to 2006 to evaluate the effect of plant density and trickle irrigation on the yields and incidence of hollow stem for early and late transplanting of broccoli. Treatments consisted of five plant densities ranging from 3.17 to 6.35 plants m–2. Each plant density was either not irrigated or trickle irrigated to maintain at least 25 mm total precipitation per week. The highest marketable yield was achieved at 5.56 plants m–2 when grown in an early transplanting with trickle irrigation in a single row with 90 cm between the row and 20 cm within the row. Overall, earlier transplanting dates were more productive. Trickle irrigation increased marketable yield by an average of 12% over the 3 yr of tests. Average head weight, head diameter, and the incidence of hollow stem decreased as plant density increased. Leaf tissue N was not affected by plant density, trickle irrigation or transplanting date.Key words: Brassica oleracea L. italica, plant density, yield, growth