Growth habit of primocane raspberry cultivars grown as long canes for summer cropping
Primocane raspberries require a long growing season and many of them are too late for cropping in the northern climate, even when grown in a high tunnel. If the primocanes are not cut down in the fall, lateral shoots in lower parts of the cane produce summer crop in the second year of the canes growth cycle. The aim of our study was to examine the growth habit of seven primocane raspberry cultivars during the second year of the canes growth cycle and thus evaluate their suitability for the production of a summer crop. Long cane plants of Autumn Bliss, Autumn Treasure, Joan J, Imara, Kwanza, Kweli, and Polka were raised, and grown in a high tunnel after overwintering. Different types of broken buds (from primary, secondary or tertiary buds) on the canes were recorded and lateral length and berry number of each node was measured during summer cropping. Of the cultivars studied here, the growth habit of Imara and Kwanza seemed to be most suitable for summer crop production as long cane plants during their second year of growth. Kwanza plants were sturdy with a high number of laterals and no need for trellising. Imara plants were more trailing with the fruiting laterals concentrated in the middle regions of the canes, and therefore needed trellising.
Palonen, P. and Laine, T. (2020). Growth habit of primocane raspberry cultivars grown as long canes for summer cropping. Acta Hortic. 1277, 183-190
Rubus idaeus, lateral shoot, long cane, primary bud, secondary bud, tertiary bud