By Clint Thompson
The emergence of fusarium wilt disease in North Florida watermelons this year is a reminder about how effective grafted plants are in overcoming the disease. Unfortunately, their growth in the Suwanee Valley region may be limited by simple economics, explains Bob Hochmuth, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Regional Specialized Extension agent in Live Oak, Florida.
“There’s a few hundred acres that are using grafted plants, but I think the two things that go against it; No. 1, the whole economic outlook for this year makes it a little more challenging to make that investment,” Hochmuth said. “The second thing is, for this region, because of the importance on earliness with that first harvest, knowing that grafted plants are going to delay the first harvest by approximately one week, it makes it really difficult from an economic standpoint.”
Later Maturity
Grafted plants have a later maturity than regular plants. A later maturity date is not ideal for South Georgia and North Florida watermelon producers who only have about a three-week period to harvest and market their crop every year.
“We’re a little bit unusual in that stance, but if you go to some of the northern areas where watermelons are grown, like North Carolina, Maryland or Delaware, Indiana, those areas have a much longer season. Even though they might be a week later, they’re still going to have multiple weeks that they could recoup that and get high yields from the grafted plants,” Hochmuth said. “Here, we have a very short window, and unless something happens in Georgia, we have a very limited window on the back end.
“If it wasn’t for that economic assessment, I think we would have a lot of grafted watermelons in this area. It’s not a question of whether it works; it absolutely works. It’s just a matter of losing that early harvest window is justifiable to go the extra expense of the plants.”
Fusarium wilt is one of the top limiting factors to watermelon production. Grafting, which is putting a root system in the ground that either doesn’t get the disease or doesn’t get it nearly as bad as the non-grafted plant, allows watermelon producers to plant a crop without fear of the disease limiting production.