Published: October 22, 2009 08:12 pm      

These late-blight facts might help out the home gardener

Back in the early 1970s, my brother and I helped my late grandmother and Uncle Mike package up tomato and pepper plants each spring for home gardeners.

During this time, it seemed that everybody had a garden and enjoyed the work, sunlight and bountiful harvest to share with family and friends. During the 1990s gardens fell out of favor primarily due to changes in lifestyle and increased income levels.

In the last year, people are expanding or starting a home garden again and I want to encourage them to continue this healthy lifestyle practice.

In July and August of this summer, I got numerous calls about late blight on tomatoes in the gardens of many people from Somerset, Garrett and Allegany counties.

At that time, I recommended a fixed copper fungicide and told many of them that I would get back with them with more information so they can reduce this occurrence next year. The susceptible crops are tomatoes, potatoes, tomatillos and vegetative petunias.

Late blight is the same blight that caused the 1840s potato famine in Ireland. The pathogen is called phytophthora infestans is Latin for “plant destroyer.” So far, there are four strains of this pathogen US-6, 7, 8, & 11. These pathogens grow on live tissue only.

This means that the winter months should kill the airborne pathogen. Garden cleanup is important this year. Place all dead tomato plants into a plastic bag and let them cook inside the bag for a couple days and take them to the landfill. Do not place tomato plants on the compost pile. Do not leave any potato cull piles around this fall and remove all volunteer potato tubers from your garden.

During the winter months, purchase two fungicides: cholorothalonil, mancozeb and or fixed coppers. Read all labels carefully and following instructions for the rate applied to these susceptible crops and rotate these protectants throughout the season.

If we get normal July temperatures of 85 degrees or more you can cut back on your spray program, because these pathogens don’t survive well in higher temperatures. Don’t grow vegetative petunias next to garden and ask your local grower if theie petunia baskets were grown from seed. If so, you should be safe.

For more information, contact your local agriculture extension agent.

Bernard W. Miltenberger

Frostburg