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The Master Gardeners
This website showcases the activities, articles, and programs supported by the Master Gardeners of Adams County, PA and Frederick and Carroll Counties, MD. It is designed to give gardening enthusiasts, near and far, the opportunity to utilize the knowledge of our local Master Gardeners.  Articles can be accessed by topic, season or author.

See Warren Penn State Extension Center Horticulture/Gardening for more information and links to local and regional gardening topics. Email: WarrenExt@psu.edu

9/4/08 If tomatoes are infected with Late Blight - are they safe for canning? A cautionary note from Extension Specialist, Luke F. LaBorde, professor in Penn State's Department of Food Science says no, they are not. Late blight is a common disease in tomatoes caused by the fungus Phytophthora
infestans. The disease thrives in cool, moist conditions and can wipe out an entire tomato crop within just a few weeks of infestation.

Infected tomato plants initially develop water soaked lesions on the leaves and stems. Under cool and moist conditions, the fruits may become infected initially with firm, dark brown lesions that rapidly become enlarged, wrinkled, and somewhat sunken. The rotted areas are usually located on the top of the fruit and may remain firm or become mushy. Both green and ripe fruits can be infected. Green fruit that is picked early and ripened indoors may develop symptoms before it is ready to eat. The USDA Complete Guide to Home Canning (1994 ed.) recommends that canners select only disease-free, preferably vine-ripened, firm tomatoes for canning. This does not mean that the fungus itself is harmful to eat. Instead, the recommendation is based on the fact that fungus infected fruit may have a higher than normal pH that could make it unsafe for canning. This is true for other fungal infections of tomato as well.

Fruit that shows severe symptoms of late blight, especially internalization of the mold into the tomato fruit, should not be used for canning. Although the USDA Guide recommends using only vine-ripened fruit for canning, tomatoes that have been picked green and allowed to ripen indoors may be canned if they show no symptoms of late blight.

Tomatoes that are damaged by frost are also not recommended for canning because the softened tissue may be quickly invaded by fungus. If the canner insists on recovering a frost damaged crop, the fruit should be picked the morning after the frost and processed that day.

Remember as always to follow the USDA Guide's recommendations for acidification: To ensure safe acidity in whole, crushed, or juiced tomatoes, add two tablespoons of bottled lemon juice or 1/2 teaspoon of citric acid per quart of tomatoes. For pints, use one tablespoon bottled lemon juice or 1/4 teaspoon citric acid. Acid can be added directly to the jars before filling with product. Add sugar to offset acid taste, if desired. Four tablespoons of 5 percent acidity vinegar per quart may be used instead of lemon juice or citric acid.

Questions or comments on this or other columns? Nancy Yergin can be reached via email at NLY1@PSU.EDU.

More Connections articles.

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Test Your Soil 

Soil test kits are available for purchase from the Warren County Extension Office, 609 Rouse Ave.  Youngsville.  The kit comes with instructions on how to properly collect soil samples.  You mail the samples to Penn State.  They will return the results to you and make appropriate recommendations. 

Information on the Soil Fertility Testing Program -  services, fees,  and soil information resources is also available at the Penn State soil test website.

Organic Gardening Web Resources

Avant-gardening: Creative Organic Gardening
Includes information on composting, soil and a free e-newsletter

Beginning Organic Gardening
For the beginning organic gardener. Lots of articles and fact sheets.

Natural Organic Gardening sources at The Dirt Doctor (www.dirtdoctor.com)
Information about organic businesses, non-profit organizations and publications recommended by the Dirt Doctor

OrganicGardening.com
Organic test gardens with photos, growing topics from A to Z, and lots of seasonal information

The Pennsylvania Integrated Pest Management Program
Publications and online resources at this A Penn State website that include fact sheets on insects, including pictures.

Soil Amendments (at the Colorado State University Extension Service website)
Soil amendment refers to any material mixed into a soil...Using organic soil amendments is a great way to turn otherwise useless products, like fall leaves and livestock manure, into compost for improving soil tilth.