Influence of different winter covers on the yield of garlic (Allium sativum) in Estonia
In Estonia the commercial production area of garlic is about 55 ha. In recent years the interest in garlic production has increased, and the local market is demanding larger amounts of garlic, mainly for fresh production. One of the problems for local growers is the winter damage of garlic plants when the temperatures are below -20°C without or with little snow cover. The aim of the present research was to find out the influence of different winter covers on the survival, yield and bulb quality of garlic. Experiments were carried out with winter garlic 'Ziemiai' in a commercial field in the southern part of Estonia in 2015-2016. Garlic was planted on October 17, 2015 and at the end of November the field was covered with floating row cover fleece, anti-frost net or 5 cm peat substrate layer. Bare soil served as control. Temperature loggers were placed into the soil at the depth of 6 cm next to garlic cloves. Row covers were removed at the end of April and winter damage of garlic was assessed. The yield was harvested on July 23, 2016. The minimum soil temperature without row covers was -8.6°C whereas minimum air temperature at the same time was -13.0°C. The minimum soil temperature under fleece was -2.5°C, under anti-frost net -3.6°C and under peat layer -1.1°C. Without covering plant survival was 78%. All covers significantly increased plant survival, which ranged from 84 to 91%. All winter covers increased total yield, which ranged from 529 to 567 g m‑2 compared to 477 g m‑2 obtained with the control treatment. Conclusively, covering of garlic fields decreases winter damage and can therefore be recommended in Nordic conditions.
Põldma, P., Moor, U., Starast, M., Mainla, L. and Karp, K. (2020). Influence of different winter covers on the yield of garlic (Allium sativum) in Estonia. Acta Hortic. 1268, 149-154
winter damage, fleece, anti-frost net, row cover, yield