Damping down confusion

[brooklynodog]

Having read the 2 popular poly tunnel books I am confused by the damping down issue. They recommend that p/t`s are regularly damped down to increase humidity. My questions are, should this apply to G/houses? What about the blight issue, does this not encourage blight growth conditions?

[rustylady]

Damping down increases humidity and decreases temperature. Plants hate being hot and dry. It's more important in greenhouses and polytunnels with concrete bases. If you have an earth base you should be OK. Blight is windborne, so should not be a problem in a greenhouse or polytunnel.

[brooklynodog]

Thanks for that Rustylady, but I lost my whole crop to blight last year (in G/house) which is why I am concerned. Also we have just had a blight alert in Somerset! My G/house has a gravel base and I use grow bags. My P/t has 4ft wide raised soil beds alongside a 2ft wide slabbed central path.

[Alice]

Hello Brooklynodog, greenhouses and tunnels can get very, very hot. The purpose of damping down is to reduce temperature when it is too hot. And also hot and humid is much less damaging to plants than hot and dry.
So unless it is too hot for the plants you have in there, there is no need to do it. But it can be a lifesaver when it is to hot.
All depends what you are growing. Tomatoes don't like temps above 25.
Can't tell you anything about blight. Never had any experience of it.
Hope it all goes great for you.

[Susie Q]

Hello everyone, I'm new to this forum but thought I'd share this with you. We had blight on our tomatoes last year, we grew them outside the greenhouse and did not have a very good crop! We are trying the hanging basket tomatoes this year and so far, they are doing really well! is there anything I should be looking out for ie pests?

Would really appreciate any advice.