What Is Wrong With My Raspberry?

Are there any purple-black cankers on young canes, cankers enlarge to encircle cane and cause wilting and death of lateral shoots?

Are the blossoms, leaves, and twigs covered with brown splotches or brownish-gray mold?

Are there small dark green circular spots on young leaves?

Are there purple-brown lesions on the stem just under the leaf or bud, usually on the lower portion of the stem?

Are there any yellow-orange pustules on the underside of leaves?

Do some of the canes have blackened tips that are bent to resemble “shepherd’s crook”?

Do canes show a lack of vigor and reduced stand, symptoms are more apparent in low lying areas of the field or 'dips' within rows?

Are the leaves distorted and yellow, clusters of small insects are present?

Are there large notches chewed in leaves, plant vigor, and development is reduced?

Cane blight is a fungal disease spread by water splash from infected to healthy canes. Always plant raspberries in full sun and an area with good drainage. Remove and destroy infected canes immediately after harvest. Avoid injuring the canes because fungus enters through wounds.

Botrytis blight is a fungal disease that spreads rapidly when cool, wet weather extends throughout the blooming period. Effective control for Botrytis is to carefully pick off and discard blighted blossoms and foliage as soon as you find them. Also, space and prune plants to encourage good air circulation and rapid drying of plants after rain. Avoid wetting the foliage when watering and avoid excess fertilization.

Raspberry leaf spot is a fungal disease spread by splashing water. As the disease progress, the spots become light tan to gray. Severely infected leaves may fall off prematurely. Remove infected crop debris and burn them. Provide proper air circulation around the plant. If the disease is severe, spray copper fungicide.

Spur blight is a disease caused by a fungus that can overwinter on diseased canes and disperse during rainfall and active wind. Thin plants to increase air circulation. Avoid wetting the foliage when watering. Avoid excessive application of fertilizer. If the disease is severe apply an appropriate fungicide to stop the spread.

Yellow rust is a fungal disease that causes these symptoms. Provide good air circulation around plants. Avoid making leaves wet when watering. Remove and destroy all debris before spring. All infected leaves should be removed. Spray leaves with sulfur early in the season to prevent rust or to treat mild infections.

Fire blight is a bacterial disease transmitted by the wind, rain splash, and insects. The infected cane may ooze cream-colored bacteria under high humid conditions. Use healthy and disease-free seed materials. Remove and burn the infected parts.

Phytophthora root rot is a soilborne disease promoted by wet soil conditions. Once the disease has been introduced to a field then there is no method of treatment. Always plant raspberries in well-draining soils or raised beds. Plant resistant varieties.

Distorted, yellow leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted, and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

several weevils are known to feed on raspberry leaves. Black vine weevil, Strawberry weevil, Clay-colored weevil all cause the same symptoms. To control them, spread a drop cloth around your plant and shake it so the adults drop. You can get rid of them after that. Spray leaves several times with pyrethrin for major infestations.

Raspberries are susceptible to several viruses. Raspberry leaf curl virus, raspberry bushy dwarf virus, black raspberry necrosis virus, raspberry ringspot virus are known to infect raspberries. Viral diseases are incurable so all you can do is remove and destroy infected plants. Control aphids as they often vector viruses.