Rick Tracy, owner of Intervale Farm in Westhampton, worked Tuesday afternoon to spray his tomato plants with a fungicide known as OxiDate, something he rarely likes to do. He considers himself a low-spray guy, but after he noticed a few gray spots on his tomatoes’ foliage last Thursday, he knew he needed to try something.
Farmers across the Pioneer Valley have been forced to get rid of plants hit with late blight, a disease that destroys tomato and potato crops by spreading spores in the air.
When it hits, it works fast, often destroying plants within a week. Many farmers try to stay ahead of the disease by spraying fungicides. For those already facing it, however, it seems the only option left is to destroy the infected plants.
“I’m going to spend every minute from now until it’s too late spraying,” Tracy said. “But, if it’s here already, there’s not much you can really do to try to stay ahead of it.”
First signs of late blight are generally gray or brown lesions on stems, discolored leaves and a white fungal growth, sometimes on the underside of leaves.
Tracy predicts that if the disease continues to grow, about a quarter of his crop could be destroyed in one of his fields. In the other, about three-fourths could be gone.
“Once late blight goes into a plant, there’s nothing holding it back,” Tracy said. “The plants will be gone in a week.”
Late blight, the same disease that caused the Irish potato famine in the 1840s, travels quickly from one garden to another. Cool, damp conditions allow it to grow and spread, making the recent rainy, cool weather in western Massachusetts perfect for the disease.
Northeast farms saw a major late blight outbreak in 2009, causing significant losses in both tomato and potato fields, according to the UMass Extension website. Since then, it has continued to show up in New England farms.
Dan Pratt, farm manager at Astarte Farm in Hadley, said this has been a rough season for his tomatoes, which have suffered from fungal disease. Most tomato diseases are fungal and destroy the foliage. This makes it difficult for tomatoes to get the sweet taste most people are used to, Pratt said.
Pratt said his farm is only going to be able to grow about one-third of the tomatoes it has in the past. Since half of the farm’s income last year came from tomatoes, this is a big hit.
“We were expecting to have an excess this year, but we definitely won’t have enough,” Pratt said.
Many other farms in the area have not yet experienced the disease. But, they are preparing.
Anna Meyer of Hart Farm in Conway said she hasn’t seen any late blight yet, but the crop will mostly likely get it at some point.
“It is pretty inevitable once you hear about it in one place,” Meyer said.
She said the best thing for the tomatoes is to keep them indoors, such as in a greenhouse. Hart Farm does an outdoor and indoor crop every year, hoping that at least the indoor crop won’t be affected by disease.
However, not every farm can grow in a greenhouse, especially farms with bigger crops. Another option to prevent the disease is growing disease-resistant types of tomatoes. However, many farmers, Tracy included, don’t like them.
For now, Pratt and Tracy are going to move their focus to fall crops.
“It’s scary to think about,” Tracy said. “Tomatoes are a big crop for us, but we’ve found out we can survive without it.”
Pratt urged home growers to educate themselves on late blight and other diseases, since the spores can move quickly from one garden to another.
“This affects the whole community,” Pratt said. “Don’t allow plants to keep growing if they’re diseased.”