Causes of Strawberry Blossom Blights and Dried Berries

Sometimes strawberry blossoms fail to set fruit, and instead, simply turn brown and dry 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 more obvious in later stages and wet conditions when the gray fuzz 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 by disease or mechanical damage. 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, as well as botrytis.

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.