Growing cucumbers in_high_tunnel

Growing cucumbers in_high_tunnel

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  Growing Cucumbers withina High Tunnel Lewis W. Jett1* and James Quinn2 Department of Horticulture, University of Missouri, Columbia, MO 65211-7140 Introduction: Cucumbers (Cucumis sativus L.) are high yielding but frost-sensitive vegetables. They yield very well as an early-season crop, but also will produce well during the summer and fall. One method to extend the production season of cucumbers is using a high tunnel. High tunnels are unheated, plastic-covered greenhouses which capture and store solar heat during the day and are manually vented to control temperature and humidity. Unlike a greenhouse, they use no fossil fuels and have much lower start-up and operating costs. Table 1. Cucumber cultivars evaluated within a high tunnel. Fall, 2005 Cultivar Days to maturityz Fruit type Seed vendor Camaro 60 European-type DeRuitery Dasher II 58 Slicing Chesmore Seeds; Harris Seeds Diva 58 Slicing Harris Seeds Genuine 48 Slicing Johnny’s Seeds Hazera 456 50 Beit Alpha-type Hazera Seeds Indy 59 Slicing Seedway; Chesmore Seeds Milligon 60 European-type DeRuitery Socrates 52 Beit Alpha-type Johnny’s Seeds Tasty Green 48 European-type Seigers Seeds Timor 45 Beit Alpha-type Seigers Seeds Tyria 56 European-type Johnny’s Seeds z Days from seeding. yRetailed from: Hydro-Gardens, Inc. Colorado Springs, CO 1 State Extension Vegetable Crops Specialist. 2Extension Assistant.
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  Methods: Eleven cucumber cultivarswere evaluated (Table 1). There are several types of cucumbers. Cucumbers grown for the fresh market are termed “slicers”. Slicing types produce fruit with seeds and a relatively thicker skin. European types, also called Dutch types or hothouse cucumbers, produce parenthocarpic fruit. That is, the fruit sets without pollination and does not produce seed. Burpless cucumbers do not have seed. European type cucumbers are typically long but have a smaller diameter than slicing types. European cucumbers have a thin skin and lose fresh weight rapidly after harvest. Beit Alpha cucumbers are also parenthocarpic but tend to be blockier and have a waxy layer on the fruit which prevents significant fresh weight loss. Three (20 ft. wide x 34 ft. long x 9 ft. high) high tunnels (Stuppy Greenhouse Mfg., Kansas City, MO) were used for this cultivar evaluation. Each high tunnel had a single layer of 6 mil plastic with 38” high sidewalls which were rolled (up or down) to manage temperature and humidity within the high tunnel. Cucumbers were direct seeded in 50 cell trays and grown as transplants for 2.5 weeks prior to transplanting within the high tunnels on 20 August 2005. Each transplant was placed in the planting hole on black plastic which had previously been in cantaloupes.(March-August 10) The cantaloupe vines (including roots) were removed one week prior to transplanting the second crop of cucumbers. The plastic mulch, drip irrigation line and mesh trellis was left in place for the next crop of cucumbers. Each plant was spaced 24” apart with rows on 48” centers. A single drip line was under each plastic mulched bed to provide water and soluble fertilizer to the growing cucumber plants. A starter solution (15N-30P-15K) mixed with Admire insecticide was applied to each transplant a day after transplanting. Flint fungicide was applied to control powdery mildew. Starting 2 weeks after transplanting, the cucumber vines were trained on the trellises by using ¾” plant clips. Water and fertilizer was applied every 3 days (8-10 lbs N/acre/week. The fertilizer used was calcium nitrate (15.5N-0P-0K-19Ca) since nitrate nitrogen is the best form of nitrogen to use for cucumbers.
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  Harvest commenced on23 September and proceeded every 3 days until 8 November 2005. Each cucumber was weighed, and a subsample of each cucumber cultivar was measured for length and diameter. Results and Discussion: Table 2. Marketable yield and count of cucumbers produced within a high tunnel.-2005 Cultivar Average fruit Average fruit Fruit wt/plant Fruit no./plant length (in.) wt. (oz.) (lbs.) de Dasher II 7.5 8.0 12.2ab 24abc Indy 7.9 8.8cde 11.1ab 20abc ab ab Tasty Green 12.0 12.4 10.9 14bcd Diva 7.1 8.1de 9.7ab 19abc de ab Socrates 6.9 7.8 9.5 20abc Genuine 8.1 10.1b 9.4abc 15bcd Timor 7.4 8.1de 9.2abc 18abc ab abc Milligon 10.0 11.4 8.1 12de Camaro 11.6 11.7ab 6.6cde 9de b cde Tyria 10.8 10.0 5.3 9de Hazera 456 5.8 4.9f 1.9f 6e LSD (0.05) 1.8 2.0 4.1 7.1 ‘Dasher II’ produced the highest yield of all cucumbers evaluated within the high tunnel (Table 2). ‘Dasher II’ is a slicing type with excellent uniformity and good tolerance to powdery mildew. ‘Indy’ also is a slicing type but produced slightly less fruit per plant relative to ‘Dasher II’. ‘Tasty Green’ was one of the earliest maturing cultivars evaluated, and this early production resulted in a high yield. The fruit of ‘Tasty Green’ is dark green with slight ridges and average 12” in length. ’Diva’ produced tender, crisp fruit with excellent taste. Socrates’ is thin-skinned, dark green cucumber with excellent quality and yield. ‘Socrates’ is somewhat tolerant of cool weather and thus may be well suited to high tunnel production in the fall. ‘Genuine’ is an early maturing slicer, but seemed to have poor tolerance to powdery mildew. The European or hothouse types, ‘Camaro’ and ‘Milligon’ did not perform well relative to most other cultivars evaluated. They seemed to lack good tolerance to powdery mildew, and should have a longer, warmer growing season than what is provided in an unheated high tunnel. The open environment of the high tunnel may not be suitable for optimal production of European type cucumbers.
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  Trellising of cucumberssignificantly improves yield and quality. All long-fruited types (≥ 10”) should be trellised to maintain good fruit shape. Slicers and beit alpha types may not be trellised, but trellising will improve yield and quality. No. Cucumbers per High Tunnel 8000 7000 6000 5000 No. 4000 3000 2000 1000 0 Dasher II Indy Socrates Diva Timor Genuine Tasty Green Millago Camaro Tyria Hazera 456 Cultivar Boxes (45 ct) per High Tunnel 180 160 140 120 100 No. 80 60 40 20 0 Dasher II Indy Socrates Diva Timor Genuine Tasty Green Millago Camaro Tyria Hazera 456 Cultivar Figure 2. Yield of cucumbers per 2500 ft2 high tunnel. Slicers and beit alpha types are typically packed as 40-45 count boxes. European types are shrink-film wrapped and sold in 16 count boxes. Conclusions: Growers should consider using high tunnels for extended season cucumber production. Cucumbers are an excellent rotation crop with tomatoes. Choose a cultivar with good yield, quality and disease tolerance.