Tomato Blight in Connecticut, July IV

Submitted by Alix on Tue, 07/21/2009 - 12:14

Mad Hatter Farm News

Hello Mad Hatters,

This week we are bracing for what is sure to be bad news for tomato crops across the northeast and certainly Connecticut.   A highly contagious fungus called “late blight” is destroying tomato plants. The spores of the fungus are always present in the soil and often kill tomato plants toward the end of the season, but with the cool wet weather we’ve been having in June and July, late blight is hitting farmers hard. The fungus spores can travel up to 40 miles on the wind. And apparently some of the current outbreak may be due to infected tomato plants sold at the big box stores like Wal-mart, Home Depot and Lowe’s.

Many commercial tomato growers, organic and non-organic, have had portions of their crops wiped out, as have many smaller boutique growers. As noted in the New York Times (“Outbreak of Fungus Threatens Tomato Crop” 7/18/09), half of the tomato crop at Stone Barns Center for Food and Agriculture in Pocantico Hills, NY, has been devastated.[1] Many of our farmer friends are struggling to save their crops, and hothouse tomatoes are also at risk. There are no curative applications for late blight, only preventatives.

Commercial non-organic growers can use a chemical called chlorothalonil (trade names Bravo or Daconil) to hold off late blight. On a normal year, a commercial grower will spray chlorothalonil once every 3 weeks, which apparently is no big deal if you don’t mind a little bit of chemical with your vegetable. But currently the big growers are spraying up to every 24 hours to try to save their crops. Reports are surfacing of field workers developing dermatitis, rashes and swelling. Late blight is also building up a resistance to this chemical, and as the season progresses, the USDA suspects that in 4 months this strain of late blight could be highly resistant to chlorothalonil. And while the fungus is supposed to be killed off in the winter, could all the spraying be setting us up for a disaster in years to come? Acute Chlorothalonil toxicity is apparently low through ingestion, but at spray rates of every 24 hours, I would be very cautious buying non-organic tomatoes from the northeast.[2]

Organic growers, like Mad Hatter Farm, have limited choices when it comes to fungicides. One product is a bacteria that is sprayed on the tomato plant, which then colonizes and eats the fungus spores as they land on the plant. This is a safe, low impact option, but it takes several days for the bacteria to colonize and the late blight fungus can overwhelm the plants. The other alternative is to spray copper. Copper is very good at preventing damage from late blight, but copper is not good for soil health and can damage fruit tissue – so in spraying it you may be saving the tomato plant but destroying the tomato fruit.

A friend of ours, who has lost half of her tomato plants, spoke to a USDA representative who told her that within the next few months, the USDA expects that there will not be a single tomato plant in the state of Connecticut that is not infected with late blight. Oh dear.

Today at Mad Hatter we do not have late blight, but the weather this week could be devastating. Late blight can wipe out your whole crop in a matter of days. We are going to begin spraying the bacterial fungicide spray, Serenade, which is approved by the OMRI (Organic Materials Review Institute). We are weighing the pros and cons of spraying copper and will let you know what we decide.

In the meantime, we ask you to support your local farmers in good times and bad, become educated consumers, ask questions, enjoy what tomatoes there are and be careful of non-organic tomatoes. For more information on late blight and chlorothalonil, please use the web-links at the bottom of the page in the footnotes.

Come rain or shine, this week at the Woodbury Farmers Market (Weds. 3:00p.m.-6:00p.m.) and Ridgefield Farmers Market (Fridays 3:00p.m.-7:00p.m.), Mad Hatter Farm will have:

·         Gourmet Lettuce Mix
·         Spicy Greens Mix
·         Marketmore Cucumbers
·         Red Express Cabbage (This is the last week)
·         Radishes
·         Carrots
·         Green Beans
·         Eggplant
·         Washington Cherry Tomatoes
·         Golden Nugget Tomatoes
·         And other surprises…

“Life is like a game of cards. The hand that is dealt you represents determinism; the way you play it is free will.” -Jawaharal Nehru

Alix and Jeff
Mad Hatter Farm
135 Music Mountain Road
Falls Village, CT 06031
T: 860-824-7635
www.madhatterfarm.com