Build-up of condensation in mini plastic greenhouse

Primrose

In certain weather conditions, (i.e. strong sunshine but sharp wind) after I've watered my seedlings in my mini plastic greenhouse I get a thick build jup of condensation inside which really reduces the light levels.
If I open the ventilation flap to reduce it, the small seedlings on the lower level can be exposed to cold winds which can damage them.
Any idea how to overcome this problem?

balloo_2

Perhaps you are overwatering after all the water does have to go somewhere. Are you watering early before the sun comes up? if you are thats good don't water when the sun is out causes scorching.

Greenhouses must have air movement for cooling. In winter, air movement is needed to reduce excess humidity, condensation, and dripping of moisture from the roof. Either greenhouse vents or fans can be used.SomeGreenhouse heaters have a cool air setting for summer

chrisaj

You need to keep the flaps open on a nice day, even if there's no sun, the radiation from the clouds will soon heat the greenhouse up and cause condensation.

Chris_Michael

Condensation occurs when the relative humidity of the air is at a point whereby the surface temperature of the walls or ceiling is low enough for the excess moisture to condense. So, if you have a large amount of excess moisture in the air and a high room temperature then the surface temperature of the walls would only have to be a degree or so lower for condensation to occur.

If the level of moisture in the air is low then the surface temperature of the walls has to be significantly lower than the internal air temperature for condensation to form. The lower the level of moisture in the air the great the temperature difference between the air temperature and the surface temperature has to be for condensation to occur.

If you can understand the above you might be able to apply it to the greenhouse but you have to remember that when you ventilate the air coming in might be damper than the air you are trying to you force out.

Hope this helps.

Chris

heynonnynonny

Keep mine open in the day now, it was just steaming hot when I opened it up!

cooking-mama

Ive been wiping mine down with kitchen roll,sorry cant think of any other solution.

Pixiechic

Thank you!! I have recently bought a pollytunnel and had put all of my plants in there and I could not work out why the leaves were starting to go a little brown and not doing that great. I just thought that it was because they were adjusting to being 'outside'. From reading this and another thread I realised taht it was because they weren't getting enough outside air and that they were just cooking away inside. I hadn't thought to air it out . So, i have opened the tunnel now and I have kept it opened but will be easy to close again if a frost comes along. Just wanted to say thanks as it would never have occured to me otherwise!