CLAVERACK–Gardeners–and customers–waiting eagerly for the taste of that first sun-warmed, fresh tomato may be disappointed this year, and without a drastic change in the weather, the disappointment may extend to those who savor tiny new potatoes.
The unusual summer has provided ideal conditions for the growth of Phytophthora infestans, the bacteria that causes a disease called late blight on both plants.
This form of blight causes more than inconvenience and consumer disappointment. Some local farmers are experiencing heavy losses because of the bacteria, which infects members of the nightshade family like tomatoes and potatoes. Experts say it is the same blight that caused the Great Irish Potato Famine of the mid-19th century.
According to Capital Region Cooperative Extension Service Regional Vegetable Specialist Chuck Bornt, three farms in Columbia County have been affected. Temperatures below 78 F. during the day, lots of rain and heavy dews, he said, have set up “prime conditions” for late blight.
Chris Cashen, who runs an organic truck/market farm in Claverack with his wife, Katie, has been hard hit. They planted two tomato crops, early and later varieties.
“What hurts the most is that we planted them very early, we covered them, the plants are seven feet tall, and we were about 10 days away from picking ripe red tomatoes.” Their loss, he said, represents “thousands of dollars worth of labor and plants and income.”
The damage may be worse on organic farms. “Organic growers have fewer tools at their disposal,” said Mr. Bornt.
A copper spray, covering every part of the plant’s foliage, can be used to prevent spread of the bacteria: It is even approved for organic farms, Mr. Cashen said. But nothing cures the disease.
Mr. Bornt said this type of blight can “go through a field within a week.”
Neither Staron Farm in Valatie nor Holmquest Farms in Claverack has experienced problems. Donna Staron says they are trying to use whatever preventive methods they can on their 30 acres of potatoes. But they’ve had customers complaining about losses in their home gardens, she said. “We’re keeping our fingers crossed.”
While the tomato crop represents “a decent amount of income for us,” Mr. Cashen says it could be worse. “We grow 40 or 50 other vegetables. We’re not a tomato processing firm.” He said that over the winter, the couple will discuss alternative ways of growing tomatoes, perhaps in a greenhouse. It’s a bigger investment, he said, “but you really can’t do this every year and make any money.”
Mr. Cashen plans to cull the affected tomatoes as “damage control,” and hope for the best for the later crop in a different field. So far those tomatoes aren’t showing symptoms. The disease is “so widespread,” he said, “everybody’s got it. People who are able to protect their tomatoes will have a very strong market, because there won’t be many of them out there.” His potatoes have not yet been affected, either, he said.
Since the bacteria don’t survive the winter in this area, Mr. Bornt doesn’t expect the blight to cause problems next year. There is “some concern” over the possibility that different strains may combine to create a more cold-hardy variety, he said, “But we’re pretty sure it won’t overwinter this year.”
For crops and gardens not yet infected, Mr. Bornt said “a little hot, dry weather would help.”