Beware of Spike in Vegetable Diseases Following Recent Storms

Web AdminCucurbits, Disease

By Clint Thompson

Cucurbit disease management is vital for vegetable growers following last week’s heavy rainfall and ahead of more rain predicted for this week.

Vegetable diseases
Examples of watermelon fruit rot caused by Phytophthora capsici (Photo credit: Dr. Pingsheng Ji)

Tim Coolong, associate professor in the University of Georgia (UGA) College of Agricultural and Environmental Sciences, discussed the impact of heavy rains saturating soils across the region, especially as watermelon harvests are finally under way.

“Like we discussed earlier in the spring, vegetable growers, ideally, would rather have it not rain and be able to apply everything that they need. Particularly now that there’s fruit on the plants, you always worry about any sort of diseases and so forth,” Coolong said. “In the cucurbit crops, phytophthora is probably the No. 1 concern being on fruit. That can show up after harvest and during shipping. I’m sure growers are very much on top of spraying for phytophthora fungicides. Of course, when conditions are really, really wet and there’s standing water, it’s hard to stay in front of it.”

According to the UGA Automated Weather Network, Tifton, Georgia, received 4.31 inches of rainfall from June 12 to June 15, compared to 1.84 inches last year. Albany, Georgia, received 7.3 inches of rainfall, compared to 0.33 inches during the same timeframe last year.

Sunshine over the weekend provided relief for growers who needed to get back in the field to harvest watermelons and apply fungicides. But it also provided ideal conditions for diseases to flourish.

“It should dry things out, but also when it gets hot like that after things being wet, sometimes a lot of diseases can spread quickly. I’m sure growers were out there spraying fungicides as soon as they could,” Coolong said. “Now that you’re in harvest, you have to deal with pre-harvest intervals. Most are fairly short, but if you have a three-day pre-harvest interval and your first opportunity to get in the field was maybe Sunday, it can make it challenging when you’re trying to get products out of the field.”

It also is a challenge considering the forecast for this week across South Georgia. Scattered thunderstorms are in the forecast all week, according to