Floriculture Greenhouse Update

Late Blight on Tomato

Friday, 25 June 2010 14:12

Update on Late Blight of Tomato and Potato for Retailers--

On 6/19 late blight was confirmed on tomato from a community garden on Long Island. The gardeners are taking out all their tomato and potato plants. On June 17 a plant pathologist confirmed late blight on tomato from a home garden in New Haven county, CT. The plants had been grown from seed by the gardener. Thus, late blight ha been confirmed in one location in New England. LB has been confirmed in NY, CT, PA, MD, KY, LA, FL and Manitoba to date this year on either tomatoes or potatoes.

Once late blight is detected, it is important to pull and destroy infected plants as soon possible. Any infected plants left in the ground have the potential to provide inoculum that can spread to other gardens and farms many miles away.

Protection with Fungicides. All potato and tomato crops should be protected with fungicides on a regu­lar basis.  Products containing chlorothalonil or copper can be suggested for home gardeners.

New Fact Sheets:

More information and photos can be found in the updated fact sheet by Dr. Sharon M. Douglas titled Late Blight of Tomato and Potato in Connecticut--2010.

And to help distinguish LB from other leaf spots on tomatoes see this new fact sheet: Recognizing Tomato Blights (University of Massachusetts)

Tina Smith, University of Massachusetts and Leanne Pundt, University of Connecticut