Early August Greenhouse Grape Harvest
To explore methods of cropping table grapes over as long a season as possible, the early ripening variety Juodupe was grown in an unheated greenhouse. Juodupe is a Lithuanian labrusca with dark-blue berries in concial, well-filled to slightly compact bunches. The berries have a pleasant blueberry flavour and the proportion of seeds (1-3 per berry) is low. A slight susceptibility to powery mildew was noted in previous years, but it was found problems could be avoided by regular spraying with water.
In the 2020 season, budburst was observed on 7th April, with flowering occurring between 26th May and 6th June. A first crop was picked on 3rd August when sugar contents had reached 13 0 Brix. By 12th August sugar contents were around 15 0 Brix and the remaining bunches were harvested. Bunch weights ranged from 35 g to 174 g, with berries up to 18 mm diameter and 3.4 g weight. The results indicate short season (~120 days) grape varieties may be cropped under cover around the same time as outdoor grown soft fruit such as blackcurrants and gooseberries in the north of the UK.
