At Flack Manor, we take great pride in the English hops that we choose for our cask ale range. The images show Stocks Farm in Worcester with photos courtesy of Paul Corbett from Charles Faram.
After the hops are harvested through September and signalled by the shorter days, material migration shifts to the roots where energy is concentrated. Keeping the roots healthy at this stage is important to ensure a healthy crop the following year. This period is known as the onset of dormancy where shoots and fine roots die, the storage roots thicken and accumulate starch and the large resting buds develop.
There are numerous articles suggesting that Hops need temperatures of at least -12 to +5°C for a period of six weeks in order to concentrate all of their energy in their roots. This can be measured in hours, as temperatures during the day will fluctuate and the desired chilling effect when reaching below 5°C for only a few hours will still concentrate the energy in the crown.
The images show the same hop yard having little problem with the winter temperatures.