2017 ASHS Annual Conference

Little information exists on the bloom and fruit characteristics of cider apple (Malus ×domestica) cultivars grown in the United States. In this study, a total of 17 cider apple cultivars, including four American, nine English, and nine French, plus one Danish standard dessert apple cultivar (Red Gravenstein, Worthen strain) commonly used for cider, all grown in northwest Washington, were evaluated from 2000–2015 for commercially relevant traits. The mean full bloom date of the 18 apple cultivars evaluated ranged from 25 Apr. to 25 May, with six cultivars categorized as early season bloomers, nine as mid-season, and three as late season. The mean bloom density rating (measured on a scale of 1-5) for all cultivars was 3.8 ± 0.6 (moderate bloom), with the bloom habit of 1 cultivar categorized as biennial, 11 as consistent, and 6 as strongly consistent. The mean productivity rating (measured on a scale of 1–5) for all cultivars was 2.9 ± 0.6 (light fruiting), with the productivity of four cultivars categorized as biennial, 10 as consistent, and four as strongly consistent. The mean fruit diameter of the 18 apple cultivars was 2.7 ± 0.4 inches (medium sized), with the fruit size of 2 cultivars categorized as small-fruited, 15 as medium-fruited, and 1 as large-fruited. For the 18 cultivars, the mean tannin and titratable acidity were 0.20% ± 0.14% and 0.54% ± 0.28%, respectively, and using the English cider apple classification system of juice type, 4 of the cultivars were classified as bittersweet, 1 as bittersharp, three as sweet, and 10 as sharp. Three of the cultivars had tannin content lower than what was historically recorded at the Long Ashton Research Station in Bristol, England for those same cultivars. The mean specific gravity of the 18 cultivars was 1.052 ± 0.007, the average predicted alcohol by volume was 6.9% ± 0.9%, and the mean pH was 3.68 ± 0.39. Classification of three cultivars in northwest Washington, based on juice characteristics, differed from their historical classification in England, likely because of differences in climate and management. Only cultivars Golden Russet (sharp), Grimes Golden (sharp) and Yarlington Mill (sweet, but borderline bittersweet) were strongly consistent in productivity, but none produced high levels of tannin; while only cultivars Bramtot (bittersweet), Chisel Jersey (bittersweet) and Breakwell Seedling (bittersharp) were consistent in productivity and produced high levels of tannin.