Causes of Strawberry Blossom Blights and Dried Berries

The warm wet weather the past couple of weeks together with high humidity is creating perfect conditions for a number of strawberry diseases.
Causes of Strawberry Blossom Blights and Dried Berries - News


Are your berries turning brown and drying up? Check to see that the pedicle is not damaged. Photo: Kathy Demchak, Penn State

Some growers are noticing that the later blossoms on their strawberries are failing to set fruit, and instead, are just turning brown and drying up.

This can be a little puzzling since the cause often is not obvious. Two things could be happening – one is that the flower itself was infected and colonized by a disease—often botrytis, which is usually fairly obvious once the gray fuzziness becomes apparent. However, a second cause is often that the pedicle (the little stem connected directly to the berry) or the tissue that connects the pedicle to the berry may have been damaged. When this happens, the flow of water and nutrients to the flower bud or developing fruit is stopped as the tissue collapses. The flower bud or tiny developing berry then simply dries up and turns brown. Anthracnose commonly causes this type of blight, especially in anthracnose-susceptible varieties.

So, how can one figure out what might be going on? It is beneficial to take a close look at other clues that are present in the planting and consider other factors such as timing, weather conditions, and variety. If symptoms showed up early while it was still cool and wet, then botrytis could be involved. If growing an anthracnose-susceptible variety, such as Chandler, perhaps anthracnose is the more likely issue. Are there other symptoms present, such as leaf spots, or lesions on runners or caps? Are there symptoms of angular leaf spot (clearing of tissue when holding leaves up to the light, or completely brown or black caps)? While more than one disease may be present at the same time, a severe case of any particular disease is likely to cause multiple symptoms on the same plant, including blossom blights and berries that fail to form.