Northern, temperate zone berry growers are busy with tunnel doors at this time. In England some have belatedly decided to install temporary doors now that the weather has changed. We had Californian weather for March but we have moved back to the Arctic for a spell now. A Californian academic commented on the radio this week that “What the British weather giveth it also taketh away”. Growers of oudoor crops are wondering what it ever gives them as we see a -3oC frost forecast with pears and apples both coming into bloom.
Scottish growers had weather that was as warm as mid Summer last week but many centimetres of snow this week! Away from the most extreme winds of snow this weather is annoying for tunnel growers but not dangerous…. but what to do about doors?
Unless the location is very sheltered, Haygrove recommend Streamline doors for temporary and fixed tunnels where extreme earliness is required. Withstanding strong winds these doors and adding to the structural wind resistance of tunnels ends, Streamline doors provide 100% sealing.
Most berry growers growing under 4-Series type tunnels on temporary sites opt for simple, low cost doors of the type shown in the image below. Makes sense…. cheap, quick to install etc.
….. But the climate is never right and every time the weather changes the grower must decide whether to spend money on labour, opening or closing OR lose yield or quality by compromising on the growing environment.
By far the best doors for field scale tunnels are ‘roller doors’. Unless the tunnels ends are staggered instead of straight of swept, roller doors can be set up to open several tunnels at once. Haygrove Farm now has many blocks kitted out with roller doors and for semi-permanent substrate fields the doors are now motorised. The new table tops have both doors and roller vents linked to climate sensors. Now we can concentrate on the plants and not the labour cost!