How to Deal with Blueberries in Summer

Karla Arboleda Berries, Pests, Research, Top Posts

By Karla Arboleda

Summer weather is in full swing in affecting Florida crops, and blueberries are no exception.

During the summer, algal stem blotch can dominate blueberry fields if not handled quickly and properly. Doug Phillips, blueberry Extension coordinator for the University of Florida Institute of Food and Agricultural Sciences, explains the important steps to take.

“In the summer when it gets hot and humid, there’s always a number of fungal leaf diseases that come out,” Phillips says. “The biggest thing for the month of June, disease-wise, is algal stem blotch.”


While growers should be scouting for certain characteristics of the fungal disease in their blueberries, there is no known eradication of algal stem blotch. Phillips recommends a routine of using copper spray, such as copper hydroxide, as they are very effective.

“One of the characteristics (of algal stem blotch) is a real paling of the leaves … to where it’s almost white,” Phillips explains. “There’s also red blotches or lesions on the stems, usually in the vicinity of where you see the paling of the leaves.” He adds that during the summer, when the reproductive structures start to grow, an orange felt-like substance can be seen on the canes and stems.


In addition to algal stem blotch, blueberry growers should stay on top of pests that have a strong presence throughout June, July and August. These include chilli thrips, spider mites and flea beetles. Phillips says growers should send samples of anything they may have questions about to their nearest Extension center.

“Another thing we recommend to do … is what we call a foliar leaf analysis, where the grower will collect samples of leaves and send them to a testing lab where they will assess the different nutrient levels in the leaves,” Phillips says. “It can inform them … if they need to adjust their fertilizer level applications.”

Summertime can also have its dry periods. Irrigation habits should stay consistent throughout the season if growers want to have a healthy harvest, advises Phillips.

“Water use is maximized by the plants during the summer because you’ve got significant canopy growth, a lot of transpiration of the plants, long days and high temperatures,” Phillips says. “It’s really important to make sure that you’re keeping the soil root zone moist, but not saturated.”

Blueberry growers can look forward to a new series of emails from the Florida Blueberry Growers Association that will provide information on what to do to help manage their crops on a monthly basis. Subscribe by emailing Visit for more information.

Share this Post