Raspberry is a perennial cane fruit grown for its summer or fall berries. Plants are productive for 10 or more years once established and spread by underground roots, forming a row over time. A short planting can supply a household with fresh fruit.
Canes are biennial: they grow vegetatively the first year (primocanes) and fruit the second year (floricanes), then die. Summer-bearing types fruit on second-year canes; everbearing (fall-bearing) types fruit on the tips of first-year canes. Knowing your type determines how and when you prune. Train canes to a wire trellis or post to keep them upright and improve air flow.
Cane Anthracnose
Small purple spots on young canes that enlarge into gray, sunken lesions with purple borders. Severe infections weaken canes and reduce fruit quality.
Prune and destroy infected canes. Improve air circulation by thinning. Apply lime sulfur during dormancy before bud break. Avoid overhead watering.
Spotted Wing Drosophila
Soft, collapsing berries with small puncture marks; white larvae inside ripening or ripe fruit.
Harvest fruit promptly and frequently. Remove and dispose of overripe or fallen berries. Use fine-mesh netting or traps. Refrigerate harvested fruit immediately.
Botrytis (grey mould)
Grey fuzzy mould on petals and stems, worst in cool wet conditions.
Remove affected parts immediately. Improve air circulation. Avoid overhead watering. Apply copper fungicide if severe.
Verticillium Wilt
Lower leaves yellow and wilt, often on one side of the plant, with brown streaking in the stem and crown tissue when cut open. Plants are stunted and decline over the season.
Remove and destroy affected plants. Avoid planting in soil that has grown infected tomatoes, peppers, or other susceptible crops. Rotate beds and improve drainage; there is no cure once a plant is infected.
Japanese Beetle
Metallic green-and-bronze beetles feeding on leaves and flowers, leaving lacy, skeletonized foliage and chewed petals.
Handpick beetles in early morning and drop into soapy water. Avoid pheromone traps, which attract more beetles. Treat soil for grubs if infestations recur yearly.