Extending the harvesting time allows the consumers to eat fresh strawberries from the spring to the autumn. It also creates the opportunity to increase profits for the growers. However, such production requires new technologies and appropriate cultivars. Studies on extending (delaying) of the fruit harvesting period of two Polish strawberry cultivars – ‘Grandarosa’ and ‘Pink Rosa’ –were conducted at the Research Institute of Horticulture in Skierniewice (Central Poland) in 2012–2013. The productivity, fruit ripening time and fruit quality of both cultivars were assessed in the open field conditions (three dates of delayed planting, frigo potted and bare-root plants) as well as in soilless cultivation in gutters under plastic canopies and in a high tunnel (delayed planting, frigo potted plants). ‘Elsanta’ was used as the reference cultivar. It was found that delayed planting of frigo plants resulted in extending the harvest time by roughly 10 weeks in field condition and up to 12 weeks in soilless cultivation under cover. Both Polish cultivars were suitable for the cultivation in the open field and under covers for the delayed harvest. In both types of cultivation the peak of harvesting was 8 to 12 days earlier in ‘Elsanta’ as compared to ‘Grandarosa’ and ‘Pink Rosa’. The overall productivity as well as average fruit weight and fruit firmness of both Polish cultivars were significantly higher in comparison with ‘Elsanta’. The production under covers was more effective than in the open field, where the high temperatures of soil and air prevailing after planting resulted in decrease of yield and fruit quality. Moreover, plants under covers did not suffer from the early autumn frosts and they were harvested in a longer period of time as compared to plants grown in the open field.

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