Will concrete wall suck moisture from soil?

[Cadalot]

Not sure a wall absorbs moisture to any extent, if it did the moisture would by definition have to go into the wall and in effect soften it. So what happens to buildings when it rains? All those '60s concrete car parks are still an eyesore and still standing rock solid.

Have you not heard of rising damp?

That's why the ground level needs to be 150mm below the damp proof course to stop spashback from rain and the capillary action within in masonry.

[Greenleaves]

Not wishing to throw the proverbial spanner in the works but......

Whilst I agree with Cads about the dpc level a lot depends upon the purpose of the wall and the make-up of the concrete. In a former property we had a huge pond that was conrete and perfectly water resistant but it was a special mix.

If the concrete wall was design to resist water it will be fine but if it is just a simple mix, tiny cracks appear and capillary action will occur, this will be more to the detriment of the wall than the soil and that cracks will grow if the water content in the wall freezes.


My understanding anyway

[veggiechicken]

It's about ten years old, and it's painted. It's not exactly a wall - It's a fence with concrete posts and concrete bases for the wooden fence panels to rest on.

Its NOT a wall - its some concrete posts and bases.
Maybe I'm a bit simple but I wouldn't thought these would cause a problem. There are concrete posts in the boundary fence here - I've never given them a passing thought - let alone worried about them.

[Cadalot]

VC actually the original posting was

I am planting vegetables in a tin border against a concrete wall .It is one of the last parts of my garden where no vegetables/flowers are growing ;-). However I am concerned with the wall drying out the soil -

I have heard a wall will suck moisture from the earth - Is this true? If so, I can put a polypropylene sheet between the wall and the earth. I will mulch it too, i'm sure that will help.

The answer provided was "Yes Masonry and Concrete will absorb water."

At different rates depending on the properties as both Greensleeves and I have stared. Good dense well made concrete will hold water and they do make waterproof concrete for use in basements where there is a high water level.

The original question was downgraded to a concrete post and gravel board !

The realistic answer is just plant in front if it and keep an eye on it and water what's there when it needs it

[veggiechicken]

Actually, Cadalot, I know exactly what the original posting was, and that the question was clarified later - but the answers weren't helping the OP!
Are you having a bad day????

[Cadalot]

Nope just clarifying that reinforced concrete, concrete blocks, and clay bricks do absorb moisture depending on their density and how well they are made and what materials they have been made from, and that capillary action works within them to a greater of lesser degree.