The Kerr Center’s tomato demonstration trial results were announced this week.
The trials were grown on the Cannon Horticulture Plots – a five acre site that features loam soil with moderately poor drainage, about 3.1 percent native organic matter, and a pH range from 6.5 to 7.0. Phosphorus and potassium levels are low and medium, respectively.
I've summarized the results with little editing and you can click on the link above for more info.
In 2008, the field was planted to an all season cover crop of sorghum-sudangrass to smother bermuda grass and build the soil. This was followed with a winter cover crop of grain rye, common vetch, and crimson clover, which was mow-killed with the mow residue used as mulch.
16 heirloom varieties were grown in the trial. Most were red, pink and purple fresh market types. All were grown from seed in their greenhouse on March 20 and transplanted to the field on April 30, when soil temperatures reached 67.
They used drip irrigation and applied the mulch over the next 10 days.
Several weeks of cold heavy rain followed. Fortunately, very few plants were lost. Because the plants set out April 30 had grown little during early May cool weather, replacements set out on May 15 readily caught up.
Varieties were laid out in short plots of three plants each and replicated twice for a total of six plants per cultivar. Transplants were set three feet apart with row spacing of six feet. Each plant had a tomato cage that measured 15 inches in diameter
and 4 feet in height. All were sanitized in advance using a light chlorine spray.
They seeded buckwheat between the rows on June 8 to encourage pollinators and other beneficial insects, and also to suppress weeds. Adjacent areas of the field were planted to purple-hull peas and
VARIETY,COLOR, BEST USE, RELATIVE YIELD, MARKETABILITY, and 1ST HARVEST
MARMANDE Red Fresh Mkt. Low Medium 26-Jun
BRANDYWINE Pink Fresh Mkt. Low Poor 1-Jul
BLACK FROM TULA Purple Fresh Mkt. Medium Medium 1-Jul
OZARK PINK VF Pink Fresh Mkt. V. High Good 1-Jul
PRINCIPE BORGHESE Red Roma Drying/Canning High Good 1-Jul
BEEFSTEAK Red Fresh Mkt. High Good 1-Jul
EVA PURPLE BALL Pink-Purple Multi-purpose High Good 3-Jul
MORTGAGE LIFTER Pink Fresh Mkt. High Medium 6-Jul
CHEROKEE CHOCOLATE Purple Fresh Mkt. Medium Medium 6-Jul
HOMESTEAD Red Fresh Mkt. Medium Good 6-Jul
ARKANSAS TRAVELER Pink Fresh Mkt. High Good 8-Jul
OLD VIRGINIA Red Fresh Mkt. High Good 10-Jul
T.C. JONES Yellow Fresh Mkt. Medium Medium 10-Jul
RUTGERS Red Canning/Fresh Mkt. V. Low Good 13-Jul
BIG MONTH Red Roma Canning/Fresh Mkt. Low Good 13-Jul
CHEROKEE PURPLE Pink-Purple Fresh Mkt. Medium Poor 16-Jul
All plants received a split side dress application of custom blended organic fertilizer on April 30 and May 18. They applied, in pounds per acre, a total NPK equivalent of 39–13–18. They sprayed all varieties six times during the season with dilute foliar sprays made predominantly from soluble fish, seaweed, humic acids, and trace minerals.
They used drip irrigation sparingly since the plants were already well mulched. It became clear that the plants were getting too much water and fruit quality suffered accordingly. A symptom they learned to recognize was the upward curling of plant leaves - apparently in an effort to expose the under-leaf stomates to sun and wind to transpire more water.
Weed control required minimal attention thanks to mulching and covercrops.
They suffered minor amounts of pest damage with tomato hornworm (Manduca quinquemaculata) in mid-June. As fruit developed, they also found significant levels of damage from both tomato fruitworm (Helicoverpa zea), tomato pinworm (Keiferia
lycopersicella), and stink bugs (Pentatomidae).
Labeled amounts of Bacillus thuringiensis (Bt) and a saponin-based surfactant were applied July 3, 7, 14,and 23.
Diseases were much less of a problem and more easily managed. Both septoria blight
(Septoria lycopersici) and early blight (Alternaria solani) appeared during the season. Labeled amounts of Serenade (Bacillus subtilis)and Seacide(fish oil) were applied at the same time as Bt, and seemed to hold these diseases in check.
Discussion (mostly unedited)
We were not at all satisfied with our management of insect pests. As already mentioned, we needed an earlier-flowering cover crop to bolster populations of beneficial insects before they are needed in the tomato crop. Also, we needed to
begin applying Bt sprays earlier in the season and make more applications.
While insect pests reduced the marketability of some of our tomatoes, radial cracking and were much greater problems. The high incidence of cracking and splitting was a consequence of the rainy growing season and heirloom genetics - few of the old heirlooms have been selected for crack resistance. Mild cracking is not
a great deterrent to farmers market and roadside sales. Severe cracking, however, is unappealing and can affect shelf life. To counterbalance
cracking problems, we often harvested fruit slightly early, rather than waiting for vine ripeness.
From a commercial perspective, the bestperforming varieties were not only those with
high yields, but also those with high marketing percentages - reduced cracking and insect damage. The heirlooms that did a good job of meeting these criteria in our trial were Ozark Pink VF, Principe Borghese, Beefsteak, Eva Purple Ball, Arkansas Traveler, and Old Virginia.
These criteria are somewhat less critical for home gardeners, especially those pursuing new taste experiences or novelty. Several of the varieties in
out trial might fill that need.
Most heirloom varieties tend to be indeterminate types. This means that they are more vining, and tend to spread the harvest over a long period of time, often producing ripe tomatoes up until frost.
Determinate types are more compact plants whose fruits tend to ripen over a shorter period of time, typically two to six weeks. Determinate types are favored by processors, growers with short marketing windows, and gardeners with limited space.
Marmande is a moderately early, semi-determinate,tomato. The fruits are red, slightly ribbed, averaging about 4-6 ounces. The Baker Creek catalog describes it as a popular old French variety, originally developed by the Vilmorin Seed Company. Marmande did not produce well in our trial, but the fruit quality was good.
Brandywine is, perhaps, the most reputable of heirloom tomatoes, touted, particularly, for its distinctive flavor. It is a potato-leafed variety.
William Woys Weaver writes that potato-leafed tomatoes first appeared in the U.S. in the 1860s,an introduction from France. According to Weaver, Brandywine did not
originate with the Amish, as widely believed, but was a commercial release from the
Philadelphia seed company Johnson and Stokes in 1889. Carolyn Male writes that it was named for the Brandywine River in eastern Pennsylvania.
There are now several Brandywine varieties in catalogs. Weaver holds that the pink variety is the original Brandywine, and the yellow Brandywine, a true mutation. Amy Goldman, on the other hand, claims that the original Johnson and Stokes release is actually the lesser known Red Brandywine, which has normal leaves and deep red fruit; the potato leafed varieties, she writes, are more properly known as Sudduth's or Quisenberry's Brandywine.
In all cases and variants, Brandywine fruits grow large and heavy, but are thin skinned and not suited to shipping. The pink, potato leafed Brandywine is prone to cracking and splitting when grown in the South.
Black from Tula originated in the Ukraine. Goldman writes that it was originally imported from Russia by the Seed Savers Exchange in 1996 and made commercially available in the U.S. in 1998.
It is among the better-known exotic tomatoes. The fruit has prominent green shoulders, rose black skin, and chocolate tinged flesh. The coloring puts some people off, while others are attracted not only by the appearance, but also by
the rich old-fashioned flavor.
The Baker Creek catalog and other sources state that Black from Tula is one of the largest purple varieties, with 8 to 12 ounce fruits. Our fruits were true to description, but smaller on average. Cherokee Chocolate, the only other dark purple
we trialed, was much larger on average.
Ozark Pink VF This pink-fruited variety was originally developed by the University of Arkansas for vine ripe harvest by market growers and home gardeners.
True to catalog descriptions, the fruit is not firm enough for shipping, but is quite resistant to cracking. The eating quality and shelf life were both
good. Our plants were also very productive.
6 HEIRLOOM VARIETY TRIALS
Pink VF was the highest yielding variety in our trial.
Ozark Pink VF has an indeterminate growth habit and was specifically bred for staked production in our hot, humid, and disease prone region.
Principe Borghese This interesting semi-determinate variety produces a great abundance of small, 1 to 2ounce grape and pear shaped fruits. In the Kerr Center trial, the fruits were firm and resisted cracking and splitting quite well. Principe Borghese is especially well suited for sun drying.
Apparently,it is common to pull whole branches and hang them outdoors until the fruit dries. In some seed catalogs, such as Pinetree Garden Seeds, this Italian variety is listed separately from the rest of the tomatoes, under foreign vegetables and, unfortunately, gets overlooked.
Beefsteak The term beefsteak is commonly used to describe a type of tomato, as opposed to a specific variety. Beefsteak varieties typically produce large, somewhat flattened fruits with thick, solid flesh and few, small seed cavities.
According to the Baker Creek catalog, the variety known as Beefsteak is a popular, standard variety, with rich, old time tomato taste.
Eva Purple Ball The origin for this variety is the Black Forest region of Germany, where it is traced back to the 1800s. Like Brandywine and Black from Tula, Eva Purple Ball ranks among the better known heirlooms.
Male writes that it is a variety without obvious faults, one that is widely adapted and performs well for just about everyone, everywhere.
Both Male and Goldman remark on the consistently shaped globular fruits that typically weigh about 4to 5 ounces. It has excellent taste for fresh market uses, but is multi-purpose.
The Southern Exposure Seed Exchange catalog claims it is well adapted to hot and humid climes, and has excellent resistance to fruit and foliar diseases. It was certainly one of our best performers!
Mortgage Lifter There are numerous lines of mortgage lifter varieties. It appears that the one we purchased is the interestingly named Radiator Charlie's Mortgage Lifter – named for the West Virginia breeder, who owned a radiator repair shop in the 1930s.
The beefsteak type fruits are mild tasting, large and smooth, often weighing in at a pound. On the down side, they crack and catface readily. Stems, too, are often hard to remove. These characteristics are apparently shared by all the mortgage lifter
varieties. Mortgage Lifter has an indeterminate growth habit and plants tend to grow large.
Cherokee Chocolate is a dusky, brownish colored mutation of the popular Cherokee Purple variety. Chocolate performed better for us than its
better-known sister, including earlier fruiting.
Homestead was developed in the 1950s for Florida growers. It has good disease resistance and, unlike many heirlooms, is good for shipping.
The fruits are red, globular, medium-sized.
Arkansas Traveler is a familiar and popular variety in our region, and has been grown for generations throughout much of the South. It tolerates heat and humidity, and is crack and disease resistant. Fruits are medium-sized, smooth
and pink/rose-colored. The flavor is good, but considered unremarkable.
Old Virginia The Baker Creek catalog tells us this variety was commonly grown in Virginia during the early 1900s. They suggest it as a good choice for globalwarming gardening, because it sets fruit well despite hot summer weather. The dark red fruits are typically 6 to 12 ounces in size, with an old time sweet tart taste.
T.C. Jones is a beefsteak fruit type that originated from Kentucky. It was the only yellowfruited variety in our trial and it proved a favorite for its taste. Its growth habit is indeterminate and the vines grow quite large.
Rutgers A New Jersey heirloom, with a determinate growth habit, it is considered fairly popular among area gardeners. We were surprised, then,
that it did so poorly for us.
Big Month An Amish heirloom, it is the only true Roma-type we included in our trial. Big Month is named because all of its fruit tends to ripen
together making a big month of harvesting and canning. Its performance was disappointing,though it might have done better in a drier year. According to the Baker Creek catalog, this variety is highly drought resistant. The summer of 2009 was anything but droughty at Kerr Center!
Cherokee Purple Like Brandywine and a few others mentioned, Cherokee Purple is one of the legendary heirloom tomatoes, touted in good part simply for being delicious.
According to Male, the variety is over 100 years old and was supposedly grown by the
Cherokee. Its genealogy, however, is questionable. Male laments the confusion and blames it on the embellished descriptions in many early seed
Apparently the name Cherokee Purple captured the imagination of seedsmen and
promoters as well as gardeners!Cherokee Purple is indeterminate and disease resistant, making it a good choice in the South. Fruits are relatively large, about 10 to 12 ounces. It yielded moderately well for us, but we encountered much cracking and insect damage.