Symptoms
Small misshaped fruit, malformed fruit, flowers that do not develop into fruit, small seeds and normal seeds on same fruit.
Similar Problems
Micro nutrient deficiencies such as boron, damage to flowers from insects (thrips, mites, tarnish plant bug, etc.) and botrytis may cause misshaped fruit.
Additional Information
Usually occurs very early in spring during frost/freeze conditions as well as cold wet weather or when row covers are used for an extended period of time.
Diagnostic Tips
Micro nutrient deficiencies such as boron, damage to flowers from insects (thrips, mites, tarnish plant bug, etc.) and pathogens (botrytis) may also cause pollination problems. Examine plants closely for insects and pathogens also use tissue testing to check nutrient status to rule these out.
Corrective Measures
When using row covers remove as soon as possible and uncover during warm days when used for extended time periods to allow wind and insect pollination.
Management
Protect flowers/fruit from freeze and frost with overhead irrigation or row covers. Introduce bees in the field at 10% bloom. Avoid using row covers during the day when plants are blooming. Avoid pesticide sprays when crop is blooming. Spray pesticides early in the morning or late in the evening to avoid bee activity.
Useful Resources
North Carolina Agricultural Chemicals Manual
Funding Sources
Funding was provided in part by the National Sustainable Agriculture Program: Sustainable Strawberry Initiative and the following sources.
Publication date: March 25, 2014
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