Growing Organic Heirloom Tomatoes: Old Challenges and New Opportunities

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1 Growing Organic Heirloom Tomatoes: Old Challenges and New Opportunities Jeanine M. Davis Department of Horticultural Science N.C. State University Photos by J. Davis and staff unless noted otherwise Jeanine Davis, 2013

2 Definition of Heirloom Tomato Variety has been available for at least 50 years. Seeds are passed on through generations. Are open pollinated. Have special characteristics, e.g., flavor, color, shape, size, earliness.

3 Heirloom tomatoes are in high demand Chefs and consumers are often willing to pay high prices for them. Prices last year ranged from $2.00 to $6.00 per pound retail. Photo from: Matthews Farmers Market

4 People love heirloom tomatoes Are flavorful Are colorful Come in unusual shapes and sizes Have fun, interesting names Have nostalgic value Are novel because they: Photo from: Fine Gardening Magazine

5 So why don t all vegetable growers produce heirloom tomatoes? They tend to be thin skinned. They crack and burst. Most are not uniform in shape and size. As a result, they don t ship well.

6 Most heirloom tomatoes have little or no disease resistance. This makes them challenging for organic growers to produce, especially in warm, humid areas.

7 They are labor intensive.

8 Yields and earliness are very variety dependent. Reliability in terms of yield and quality is often much less than with hybrids. There can be be variability from seed lot to seed lot.

9 BUT, production of heirloom tomatoes can be quite profitable. 4,350 plants/acre (24 inch spacing; 5 foot centers) Red Brandywine produced 9.2 lb mkt fruit/plant Retail price of $2.00 per pound Potential gross return: $80,040 per acre An Iowa State Univ. budget shows potential net returns (at $1.75 per pound) of $547 per 400 sq. ft. of bed space.

10 This is why we have been conducting studies on organic heirloom tomatoes since 2003.

11 How do you grow organic heirloom tomatoes?

12 Where summer rains or morning dew are common, I recommend growing in greenhouses or high-tunnels. Provides the best protection from foliar disease and fruit crack.

13 This won t solve all problems, but usually more successful than outdoor production. Is more expensive than field production. Many growers do some of both. Photo of Peregrine Farm by Debbie Roos

14 Follow basic recommendations for organic greenhouse tomato production Photo of Lee Farm by Debbie Roos

15 Many growers want to produce heirloom tomatoes outside.

16 Almost all heirloom tomatoes are indeterminate varieties that need taller and stronger support than the standard shortstake, Florida weave system can provide.

17 Most commonly used and reliable method is oldfashioned high trellising

18 Position 7-8 feet long posts (2-3 inches in diameter & not pressure treated) 15 feet apart in the row.

19 Space plants 8-12 inches apart in the row. Anchor plants by strings top & bottom. Train plants to single stem.

20 Black plastic mulch, or landscape fabric, and drip irrigation help reduce disease and allow for easy supplemental fertilization.

21 Short-High Stake System Start out with standard (3-4 foot high) staked system. Space plants inches apart.

22 Add taller stakes (5-6 ft long), every other stake, right before putting on last string on short stake.

23 In this system, plants need to be topped when they reach the top of the stakes. Photo from Tomatofest

24 In both systems suckers must be removed and plants trained to the strings once or twice a week. If a main stem is broken off, a sucker can be trained to take its place.

25 There are hundreds of heirloom varieties to choose from and we ve grown dozens of them! Brandywine Photos from: Appalachian Seeds, Tomato Bob, and Trade Winds Fruit Stupice

26 The three varieties that had the best yields and consumer acceptance in our trials: German Johnson 76 days From VA and NC. Pinkred fruit are about 1 lb. Plants are productive but with little disease resistance.

27 Cherokee Purple 85 days Fruit ripen to a unique dark, dusky pink/purple. Excellent flavor. Good resistance to Septoria.

28 Mr. Stripey 56 days Huge crops of red fruits with yellow-orange stripes. Rich, tangy flavor. A favorite for taste and color.

29 Brandywine is a perennial favorite, but there is a lot of variability between seed sources and it doesn t rate that high in taste tests. Photo from bonnieplants.com

30 Our tomato breeder, Randy Gardner began developing heirloom type hybrids to deal with some of these issues. His successor, Dilip Panthee, has continued to develop more of these.

31 Objectives: increased disease resistance, less cracking, improved nutrition and better shipping qualities while maintaining flavor and other characteristics consumers love.

32 Heirlooms Heirloom-type hybrid

33 In 2009 we grew 20 varieties of tomatoes; 11 were heirlooms and 9 were new heirloom-type hybrids with late blight resistance.

34 These are some of the heirloom varieties we grew Pink Brandywine Persimmon Akers West Virginia Black Plum Arkansas Traveler Orange Banana Cherokee Purple Mr. Stripey

35 These are the heirloom-type hybrids we grew NC NC 089 NC 085 NC NC 0694 NC NC NC NC 131L

36 The two heirloom-type hybrids, NC and NC showed superb disease resistance, gave high yields of excellent quality fruit, and were the two top rated varieties in the taste tests.

37 We grew heirlooms and several heirloom-type hybrids in two organic systems, a conventional system, and an untreated control. Organic 1: Brandt Sporatec and Ecotec. Organic 2: Serenade, copper, Dipel and Neem oil.

38 For three years, , yields from the organic systems was as high or better than in the conventional system. Serenade

39 Eventually came up with a system using Sporatec, Ecotec, and Saf-T-Side with Serenade, Neem, Dipel, and copper.

40 In 2009, late blight came in very early and was quite severe. This is an example of what many commercial, certified organic farms in our area experienced. This photo was taken on August 20.

41 In our trial, late blight was evident on only a few of the most susceptible heirloom varieties on August 21.

42 Within a week, late blight had made rapid progress through the field. Some of the heirloom varieties succumbed very quickly, even with regular sprays.

43 But the heirloom-type hybrids with late blight resistance continued to produce throughout the season.

44 By early October, this is what all the heirloom plots looked like. The sprays delayed the progress of the disease, but could not stop or control it.

45 But this is what the heirloom-type hybrids with late blight resistance and the organic spray schedule looked like!

46 Take home message: Heirloom tomatoes can be grown organically, but they are vulnerable to foliar diseases and cracking. Growing in a high-tunnel or greenhouse is the best insurance for obtaining a healthy crop.

47 We don t have the perfect spray program yet, but there are materials that will help. Growing in a staked system is easier, but yields will probably be lower than on a trellis.

48 The new heirloom-type hybrids have disease resistance packages that are attractive to many organic growers. Some of the new heirloom-type hybrids taste as good, or better than, the favorite heirlooms.

49 Our breeder is also developing openpollinated heirloom-type tomatoes with late blight resistance!

50 These studies were funded by the N.C. Tomato Growers Association, U.S.D.A., and Brandt.