Extension Master GardenerSM Volunteers of Buncombe County

tomatoes

What Can Go Wrong with Tomatoes?

What can go wrong with growing tomatoes? Almost everything! What can go right with planting tomatoes in our home gardens? Enough to keep us growing them!

Tomatoes ripening on the vine_Todd Heft_CC BY-NC 2.0_Flickr
Tomatoes ripening on the vine

What’s the problem?
Let’s face it—there are lots of challenges with homegrown tomatoes. They wilt, they spot, they crack, they dot, they blotch, they rot. Whew! The list goes on. Few vegetables—or fruits, which are what tomatoes are—are more challenging.

Helpful hints
Try following these guidelines:

  • Decide on varieties that are well-suited to our area, bred for disease resistance, and meet your eating preferences.
  • Select healthy bedding plants or start indoors from seeds 6 to 8 weeks before the expected last frost date.
  • Wait to plant until after all danger of frost has passed, usually after Mother’s Day for Buncombe County.
  • Choose a location that receives at least six hours of sun a day.
  • Plant in well-prepared soil, rich in humus, with a pH level of about 6.0 to 7.0 (find out with a soil test).
  • Maintain uniform moisture and mulch.
  • Avoid overhead watering which can promote disease.
  • Stake or cage your plants because of their vining tendencies.

What to watch for
Although there are myriad tomato problems, most are rare. Five of the most common concerns and their solutions:

  1. Bacterial spot produces small chocolate brown spots on leaves and fruit. Recommended controls are to use treated seed, apply fixed copper bactericide, avoid overhead watering, remove old plant debris, and rotate your planting area.
  2. Blossom end rot caused by calcium deficiency produces dark-brown leathery spots on the blossom end of fruit. Prevent by liming your soil (based on soil test results) and keeping your plants evenly moist—be sure to water plants during dry periods!
  3. Sunscald produces papery white areas on the side of fruit facing the sun or yellow-orange blotches at the stem end that do not ripen. Proper planting and maintenance help prevent foliage diseases that can cause leaf drop and expose fruits to too much sun.
  4. Cracks in fruit also result from an uneven moisture supply. Tomatoes may need to be watered every 2-3 days, especially in dry weather.
  5. Flea beetles produce many tiny holes in leaves. Tomatoes will tolerate a great deal of flea beetle damage, but if damage is excessive, ask about an approved pesticide.

Preventing problems
To prevent disease in future years, do not compost plant debris. Plant tomatoes in a different location at least every third year. Then, watch your tomatoes grow! If you have a bad year, don’t give up! There’s always hope for the following season.

Consider the wisdom in John Denver’s song from his 1988 album Higher Ground:

Homegrown tomatoes, homegrown tomatoes
What would life be without homegrown tomatoes?
Only two things that money can’t buy
That’s true love and homegrown tomatoes! 

Article written by Mary Alice Ramsey, Extension Master GardenerSM Volunteer.

Learn more 

Gardening in the Mountains lecture:
All Things Tomato
by Dr. Randy Gardner, Professor Emeritus, Horticultural Science, NCSU
July 19, 2018, 10 a.m. to noon
Folk Arts Center, Asheville, NC
Watch for details in early July blog announcement. 

Growing Tomatoes in the Home Garden
by NC State Extension

Late Tomato Blight Is Here
by Debbie Green, Extension Master Gardener Volunteer, July 2015

Research on Truffles and Stink Bugs and More—At the Mountain Horticultural Crops Research and Extension Center

Have you ever heard of the Mountain Horticultural Crops Research and Extension Center? If so, you may think of apples, tomatoes, or Christmas trees. Located on a hill overlooking the Mills River valley, under the direction of Tom Ranney, the J.C. Raulston Distinguished Professor in NC State University’s Department of Horticultural Science, the center has become a regional and national leader in plant and entomological research.

Mountain Horticultural Crops Research and Extension Center, Buncombe County, NC
Mountain Horticultural Crops Research and Extension Center

Certainly, you’ll find the Center’s scientists working on ways to improve the production of the crops that are so important to Western North Carolina’s economy. But during the past 28 years, the Mountain Crop Improvement Lab team has developed and introduced almost 30 new plants ranging from compact evergreen dogwoods, to big, bold ornamental grasses, to hydrangeas with bright pink blossoms. And plant introductions are just one type of new discovery coming out of the center.

Truffles!
Today you’ll find researchers working on some surprising and even exotic projects, such as Black Périgord truffles.

Truffle (Tuber melanosporum) from first harvest at Mountain Horticultural Research Center in Buncombe County, NC, Nov. 20, 2017.
Truffle

The Black Périgord truffle (Tuber melanosporum) is native to Provence, France, and a favorite among chefs for an intense flavor that compliments dishes featuring meats, cheeses, and eggs. Often mistaken for a mushroom, the truffle is actually part of the taxonomic group Ascomycetes. So, what is this highly sought-after, extremely expensive, and valuable gastronomic delight doing in western North Carolina?

Through a grant from the Specialty Crop Block Grant Program administered by the NC Department of Agriculture and Consumer Services, Jeanine Davis, Extension Specialist on Herbs/Organics/Specialty Crops/Vegetables, and her team at the research center, evaluated and developed methods for monitoring truffle colonization in truffle orchards. After seven years of hard work in collaboration with the Carolina Truffiéres, and with the able assistance of the Truffle Dog Company, Jeanine harvested the first Black Périgord truffle in November 2017. For current and aspiring commercial truffle growers in Western North Carolina and the Piedmont, this was big news and proof that this ancient and highly prized crop can succeed in North Carolina. 

Brown Marmorated Stink Bug (Halyomorpha halys)
Brown Marmorated Stink Bug

Stink bugs?
Researchers at the Center’s Walgenbach lab, are seeking to solve age-old fruit tree and vegetable industry pest management problems. The brown marmorated stink bug (BMSB, Halyomorpha halys), for example, first identified in North Carolina in 2009, has devastated many crops, including tomatoes, peppers, corn, apples, peaches, and soybeans. Today, the lab is part of a team consisting of more than 50 scientists nationwide who are working to understand this insect’s biology and devise pest management strategies. 

And more…
Take a little time to get acquainted with the Mountain Horticultural Crops Research and Extension Center and the scientists who are making a difference in agriculture locally and across the Southeast through the Center’s website, which is packed with timely information for home gardeners and commercial growers. In August, you may want to attend the center’s annual Tomato Day. It’s a great opportunity to hear the scientists present their research findings, learn about new varieties, taste the fruits of their labors, and return home with a bag of luscious, locally grown tomatoes.

To find out more about registering to attend Tomato Day and other offerings sponsored by the center, visit https://mountainhort.ces.ncsu.edu/ throughout the year.

To read the full story about harvesting truffles in WNC, go to “We Produced Our First Black Périgord Truffles!” at https://newcropsorganics.ces.ncsu.edu/2017/11/we-produced-our-first-black-perigord-truffles/

For more about brown marmorated stink bugs: https://entomology.ces.ncsu.edu/brown-marmorated-stink-bug-in-north-carolina-3/

Article written by Janet Moore, Extension Master GardenerSM Volunteer.

Blight-Resistant Tomatoes: WNC Leads the Way in Research

There are two words that elicit a deep sigh and considerable head-shaking from backyard and commercial vegetable gardeners: tomato blight. 

A costly and deadly pathogen
Of the tomato blights, the deadliest is late blight caused by Phytophthora infestans, which infects some members of the Solanaceae plant family, especially tomatoes and potatoes. Although this pathogen superficially resembles a fungus, it is an oomycete that is more closely related to brown algae. This is the culprit that produced the Irish potato famine in the 1840s, so to say it’s a problem is an understatement!

For the home gardener, late blight is the destroyer of a beloved summer treat—a freshly picked, vine-ripened tomato, bursting with flavor and warm from the sun. The pathogen overwinters in infected potato tubers. Its spores are carried by the wind, which means that it spreads easily. Once it starts, it is next to impossible to stop.

Conditions favorable to blight
Don’t be fooled by its name. Late blight isn’t limited to later in the growing season. It can develop anytime between early and mid-season, depending on weather conditions, and it is a threat wherever tomatoes are grown.

The very things that tomatoes need to grow create conditions favorable for Phytophthora infestans to take hold—plenty of moisture (rain, dew, irrigation, and fog) and temperatures between 64 and 71°F. Under the right conditions, the disease lifecycle can occur in as little as five days and can spread quickly any time humidity is over 80 percent for two days or more. There are many days when conditions are just right in WNC for tomato blight! It is for this reason that NC Cooperative Extension tracks and reports where the disease is appearing and how quickly it is spreading from farm to farm and county to county. You can also follow the disease each year through the USA Blight website (https://usablight.org/).

Prevention and control strategies
Phytophthora infestans is a formidable adversary for any gardener and requires multiple strategies to combat it. Prevention and control are particularly challenging for organic gardeners and farmers. Choosing the right location for tomatoes can help. Full sun, good air movement, reduced leaf wetness, and well-drained soil all help plants stave off the blight for as long as possible. Chemical products may slow down the spread of blight, but need to be applied frequently and on ALL plant surfaces with every application. It’s a lot of work.

WNC, a leader in tomato research and development
There is some good news on the horizon for tomato growers worldwide! Unlike infected potato tubers, tomato seeds do not transmit the blight pathogen. This makes it possible for researchers at Western North Carolina’s Mountain Horticultural Crops Research and Extension Center in Mills River, Henderson County, to develop tomato varieties resistant to Phytophthora infestans and many other tomato diseases.

Dr. Dilip Panthee, Associate Professor of Horticulture at North Carolina State University (NCSU), leads this research. Developing disease-resistant, higher-yielding plants for North Carolina’s $30-million-a-year tomato industry will reduce the global economic impact of diseases like Phytophthora infestans.

It was Panthee’s work on tomato breeding in his native Nepal that grabbed the attention of NCSU. “You’ll find tomatoes growing on every continent except Antarctica. We tend to associate them with Mediterranean food, but tomatoes are a favorite ingredient world-wide,” Panthee said in an April 2015 interview. “The varieties we are creating are important for two reasons. First, we are reducing the need for farmers to use pesticides, and we know that is good for the environment. Second, we are creating fruits with better food quality, both in flavor and appearance. That means greater availability of nutritious fresh tomatoes, particularly in developing countries.”

Disease-resistant tomato varieties
Working with NCSU professor emeritus Randy Gardner (the man behind ‘Mountain Pride’ and many more tomato varieties), Panthee developed ‘Mountain Merit,’ a high-yielding, fresh-market cultivar that is resistant to three tomato plant problems—late blight, tomato spotted wilt virus, and root-knot nematodes. Panthee also developed ‘Mountain Majesty,’ a large tomato with improved fruit color and resistance to tomato spotted wilt virus. Both are commercially available.

Panthee’s latest creation is ‘Mountain Rouge,’ a pink heirloom-type hybrid that is also resistant to early and late blight, as well as root-knot nematodes. “The flavor of this tomato is excellent,” Panthee says. “And its heirloom appearance makes it very appealing to commercial growers and backyard gardeners.”

Because the Mountain tomato series (‘Mountain Pride,’ ‘Mountain Rouge,’ ‘Mountain Merit,’ and ‘Mountain Majesty’) was developed here in Buncombe County, it is well-suited to local growing conditions. You’ll find one or more of the cultivars in the series throughout the planting season at area garden centers.

Learn more
To learn more about the important tomato breeding work being done at the Western North Carolina’s Mountain Horticultural Crops Research and Extension Center in Mills River, go to http://mountainhort.ncsu.edu/fletcher/programs/tomato/. Better yet, plan a visit in late summer 2017 for Tomato Field Day, talk to the experts, and taste the fruits of their labors.

Article written by Janet Moore, Extension Master Gardener Volunteer.

Resources
http://www.apsnet.org/edcenter/intropp/lessons/fungi/oomycetes/pages/lateblight.aspx

Contact Us

Buncombe County Extension Office
49 Mount Carmel Road
Asheville, NC 28806
Helpline 828-255-5522

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