Research report from OSU's North Willamette Agricultural Research and Extension Center
Delbert Hemphill
OSU Dept of Horticulture, NWREC
The two 1980-81 trials were seeded on August 5 and 15, and transplanted on September 11 and 17, respectively. In addition to fertilizer applied before planting, 100 pounds N/acre was sidedressed on March 2, 1981. In 1981-82, the trial was seeded on July 30 and transplanted on September 2, 1981. Calcium nitrate was applied at 50 pounds N/acre on January 25, 1982. Ammonium nitrate was applied at 60 pounds N/acre on March 11 and at 50 pounds N/acre on April 5, 1982.
In 1980-81, Armado April was the best of the early to mid-early varieties in yield and quality (Table 4). Armado May and Maya were the superior mid-to-late lines. Because of the very mild winter, there was no winterkill and all varieties made some growth throughout the winter. Early maturing varieties such as March and Superb Early White were exposed to night temperatures as low as 20°F after curd formation had started. However, damage was slight. Cold weather in February and March retarded development of foliage; plant size was smaller than normal for all but the latest cultivars. Nearly all cultivars had a russeting of the leaves and curd, perhaps because of crane fly or Hylemya fugax larvae, mildew (Peronospora), or black rot (Xanthomonas). Quality was significantly reduced. These problems had not occurred in previous trials.
Twenty varieties, with more than a two-month spread in maturity, were included in the 1981-82 trial. The 1981-82 winter was cold; on several nights, temperatures in the low teens (°F) were recorded. Plants made essentially no growth during the winter, and a cold, dry spring further retarded plant development. Peak harvests averaged two weeks later in 1982 than in 1981. The earliest varieties, such as Superb Early White, March Early, Morse's March, Armado Quick, and Preminda, did not size sufficiently to produce acceptable yields (Table 5), although each produced some heads with adequate curd quality. The mid-early variety Armado April also had low yields, although curd quality was good. The best combination of yield and quality occurred with mid-maturity varieties such as Maya, Arminda, and Inca. Inca was included in the trials for the first time and looked promising for a mid-early to middle maturity line. Late cultivars such as Midsummer, June, and Vision had excellent gross yields but poor curd quality. In general, the earliest varieties suffered the greatest degree of winterkill. Disease pressure was low in 1982 and no fly larvae were found in the heads.
Table 6 presents a summary of relative maturity of all varieties included in trials through 1982. Averages are for two or more years except as noted. The span of peak harvests from the earliest (Morse's March) to the latest cultivar (Vision) is nearly 60 days. Armado April was used as a standard for comparison, with other cultivars given in terms of days earlier or later maturity than Armado April. Descriptions of the varieties included in these two trials are found in Table 7.
Table 4. Overwinter cauliflower variety trial, 1980-81 Mean head Harvest range Est. gross Variety Source wt.(pounds) First Peak Last yield (tons/acre) A. First planting (transplanted 9/11) April 3Z 0.84 4/01 4/13 4/21 4.0 Armado April 4 1.43 3/16 4/01 4/10 6.9 Armado May 2 1.90 4/01 4/16 5/01 9.2 Armado Quick 4 1.20 3/19 3/23 4/01 5.8 Armado Tardo 2 NMY 4/10 NM NM NM Arminda 4 NM 4/01 NM NM NM Heralda 2 1.04 3/16 4/01 4/01 5.0 March Early 3 0.98 3/09 3/16 3/27 4.8 Markanta 2 NM 4/10 NM NM NM Preminda 2 1.15 3/16 4/01 4/01 5.6 B. Second planting (transplanted 9/17) Aprilex 2 1.61 4/06 4/21 5/01 7.8 Armado Clio 4 1.71 4/21 5/01 5/14 8.3 March 2 0.85 3/09 3/09 4/01 4.1 Marchpast 2 1.36 3/23 4/01 4/16 6.7 Maya 1 1.52 4/24 4/27 5/11 7.4 Maystar 2 1.55 4/10 4/27 5/11 7.5 Midsummer 2 1.84 4/27 5/14 5/18 8.9 Mirado 4 1.06 4/21 5/01 5/05 5.1 Superb Early White 2 0.74 3/09 3/16 3/23 3.6 Vision 2 1.44 5/01 5/14 5/22 7.0 Zl=Bejo Zaden, 2=Elsoms, 3-Ferry Morse, 4=Royal Sluis. YNM: not measured. Table 5. Overwinter cauliflower variety trial, 1981-82 Mean Est. gross Yield of Harvest Range head wt. yield #1 heads MeanY Variety Source First Peak Last (pounds) (tons/acre) (tons/acre) grade April 3Z 4/23 4/30 5/07 1.22 5.2 3.5 1.4 Aprilex 2 4/30 5/03 5/17 1.24 6.1 3.8 1.4 Armado April 2,4 4/01 4/13 4/23 1.08 4.6 2.9 1.4 Armado Clio 2,4 5/03 5/14 5/17 1.47 8.5 4.4 1.6 Armado May 2,4 4/16 4/30 5/11 1.35 7.0 4.1 1.6 Armado Quick 2,4 3/16 4/13 4/26 0.72 3.1 1.8 1.5 Armado Tardo 2,4 4/26 5/07 5/14 1.07 6.2 3.6 1.5 Arminda 4 4/30 5/07 5/14 1.89 6.9 5.0 1.3 Inca 1 4/16 4/23 5/07 1.65 8.0 6.4 1.4 June 2 5/15 5/17 5/28 2.23 10.2 0.8 1.9 March Early 3 3/29 3/29 4/13 0.32 0.9 0.2 1.8 Marchpast 2 4/13 4/23 4/26 1.57 5.2 4.6 1.2 Markanta 2,1 4/23 5/03 5/07 1.30 5.1 2.6 1.7 Maya 1,2 4/30 5/07 5/17 1.86 7.9 5.5 1.4 Maystar 2 4/26 5/07 5/14 1.54 8.4 4.4 1.6 Midsummer 2 5/11 5/21 5/28 2.03 7.4 0.0 2.0 Morse's March 2 3/16 3/16 4/02 0.52 1.6 0.4 1.8 Preminda 2,4 3/19 4/20 4/23 0.84 4.1 2.2 1.5 Superb Early White 2 3/16 3/29 4/23 0.46 1.4 0.4 1.8 Vision 2 5/25 5/25 5/28 1.98 11.1 2.6 1.8__ Z1 Bejo Zaden, 2 = Elsoms Seeds Ltd. 3 = Ferry Morse 4 = Royal Sluis. When two sources are listed, the seed lot from the first source listed was used in the trial. YGrade 1.0 = all heads free of defects; tight, white curd. All heads given a score of either 1 or 2. Grade 2.0; all unacceptable. Table 6. Relative maturity of overwinter cauliflower varieties compared to Armado April Days earlier orZ later than A. April Varieties -20 to -11 Morse's March, March Early, Superb Early White -10 to -3 Armado Quick, Preminda -2 to +2 HeraldaY, Armado April +3 to +10 Marchpast, Barrier ReefY, IncaY +11 to +20 April, Armado May, Aprilex, Markanta +21 to +30 ArmindaY, Armado Tardo, Maystar, Maya, MiradoY, Armado Clio, Pinnacle Over +30 JuneY, Midsummer, Vision Z Within each category, varieties listed in order of maturity. YBased on one year of observations. Table 7. Description of varieties in 1981 and 1982 trials April: Few leaves, poor cover. Small heads but better than average curd quality when protected. Usually no leaves or bracts in head. Aprilex: Fair to good cover. Good curd quality. Yield only fair for mid-maturing cultivar. Armado April: Good cover on larger plants. Excellent curd quality on well-sized plants. Fair yield. Best of early cultivars. Armado May: Good cover. Fair to good yield. Tendency to leaves in head but good curd quality. Armado Quick: Poor cover, small size. Too early for cold winter/spring. Heads small but curd quality usually better than average. Armado Tardo: Good cover, but yield and head size small for mid-maturing variety. Multiple stems. Arminda: Good cover, yield, head size. Very good curd quality. Heralda: Fair cover. Poor protection from wrapper leaves but older leaves form stovepipe. Poor yield, fair quality. Inca: Good cover, good plant size for early to mid-maturity range. Good yield, head size, quality. June: Good cover and plant size. Late maturing. Poor curd quality. "Fuzzy" curds, leaves and bracts in head. March Early: Too early to size sufficiently. Poor yield, curd quality. Thirty percent winterkill. Marchpast: Good cover, but small to medium size plants. Good head size for mid-early variety. Fifteen percent winterkill. Very good curd quality. Markanta: Good plant size but only fair cover. Low yield for mid-maturity variety. Very prone to green stems. Fifteen percent winterkill. Maya: Good cover, yield, head size. Good curd quality. Best of mid-maturing varieties. Maystar: Good cover and yield, but only fair curd quality. Low density heads. Midsummer: Good cover, large plants. Late maturing. Multiple stems. Large heads but very poor curd quality: "fuzzy", bracts in head. Mirado: Good cover, medium size plants. Fair yield, Conical, knobby curds. Morse's March: Poor cover, small plants. Too early to size sufficiently. Poor curd quality. Average of 35 percent winterkill. Preminda (Armado Primo): Poor cover and plant size. Too early to size sufficiently. Average curd quality. Superb Early White: Poor cover and plant size. Too early to size sufficiently. Poor curd quality. Thirty percent winterkill. Vision: Good cover, large plants. Late maturing. Excellent gross yields but curd quality poor. "Fuzzy" curds, bracts in head. Multiple stems. Superior to other late varieties.