Better crops with plant food.

v.1-2 (1923-24); v.1-2 1923/24; v.5-6 1925-26; v.6-8 1926/27; v.7-9 1926-27; v.9-11 1927/28; v.10-11 1927-28; v.12-13 1929; v.14-15 1930; v.16-17 1931-32; v.16-17 1931/32; v.18-19 1932-35; v.18-19 1932-1935; v.20-21 1935-37; v.20-21 1935-1937; v.22-23 1938-39; v.22-23 1938/39; v.24-25 1940-41; v.24-25 1940/41; v.26-27 1942-43; v.26-27 1942/43; v.28-29 1944-45; v.28-29 1944/45; v.30 1946; v.30-31 1946/47; v.31 1947; v.32 1948; v.32-33 1948/49; v.33-34 1949-50; v.35 1951; v.36-37 1952-53; v.38-39 1954-55; v.40-41 1956-57; v.42-43 1958-59