Disease Management: Onions Vulnerable Amid Rainfall, High Temperatures

Clint Thompson Disease, Georgia, Onion, Top Posts

UGA Extension photo/Shows botrytis disease in onion plants.

Field conditions are conducive for disease pressure to increase in Vidalia onion fields in Southeast Georgia. That’s why Chris Tyson, University of Georgia Extension Area Onion Agent at the Vidalia Onion & Vegetable Research Center in Lyons, Georgia, is imploring farmers to stay on top of their fungicide sprays.

“Looking around the fields last week, we definitely saw more disease showing up. Some of the fungal diseases like botrytis and stemphylium, we saw them showing up. That is expected this time of year,” Tyson said. “But they’re definitely showing up now that we’ve had warmer weather. We just want everybody to stay on track to manage that and all the other diseases, too.”

Excessive Rainfall

Like most of South Georgia, the Vidalia onion region received its fair amount of rainfall during February. According to the University of Georgia Weather Network, Vidalia, Georgia received 6.35 inches between Feb. 1 and Feb. 22. Then temperatures increased a week later. But this week, there was more rain, especially on Tuesday and Wednesday where 2.51 inches were recorded.

Despite the weather challenges, the onion crop looks good, overall, says Tyson. But as harvest nears, now is not the time to let up.

“We’re at a period of time in the crop where harvest for some of the early maturing onions is probably just about a month away. It seems like it’s right here, but we still have a long way to go even for those onions that will be ready soon; and then for some of the longer season ones that will be ready in six weeks or seven weeks. We still have a long way to go,” Tyson said. “We’re not out of the woods yet. We know from past experience that a lot can happen in the final few weeks before harvest. We’re keeping our fingers crossed right now because everything does look good at this point.”