Rain shadow of fences

squirrelpie

I never understand why people say that fences create a rain shadow, as in one recent article I read. Can anybody explain?

When I think about it I see the same amount of rain falling over the whole area regardless of whether there is a fence there. Sure some rain might be blown onto the fence if there is wind, but then the rain will run down the fence and land on the soil as before. So there might be a slightly uneven distribution very close to the fence but surely the water will move through the soil and roots will find their way to the water so is it really a problem?

philippasmith2

Fences will usually absorb some rain water and if you have a fairly constant prevailing wind whilst raining which hits the back side of your fence, the rainfall to your border will be reduced to a greater or lesser degree.Much depends on what you actually plant close to the base of your fence. Whether or not it proves to be a problem is something only you can be certain of in your particular circumstances.
I

Loxley

A fence will block the rain falling directly on the leeward side of it, for a couple of feet or so. Because of the angle of the rain. Yes the water will seep through the soil but what if the soil is dry, and the rainy weather is brief? It might only have chance to seep into the top 3 or 4 inches, before it is taken up by plants. In which case it has no chance of reaching the 'rain shadow' area. 

Obelixx

It's pretty obvious really.  How often do you see rain falling vertically without any wind?  The rain shadow is on the side of the fence that is not in the prevailing wind.  More often than not it's negligible in winter but, come summer, if you're trying to clematis and climbing roses and other thirsty plants on the leeward side of the fence the rain shadow effect can be seriously bad for your treasures.