[mattswanathome]

Hi, I wonder if anyone can advise me. I recently bought 6 acres of mixed woodland and open scrub in mid Wales, part of which I want to grow veg on. This area, which is flat, was covered in large clumps of soft rush which I have removed by hand, leaving mostly bare earth and a few patches of grass and other vegetation. The soil is clay and in some places stony, and is strongly acidic (pH 5). It has been left fallow for many years, prior to that it was grazed by sheep. There are quite a few tree stumps dotted around.

I want to create raised beds, ideally to start planting next year. I know the soil needs lime to raise the pH level, and I'm aware that I need to wait at least 3 months after that before adding compost (which counteracts the lime's effects).

If I lime the whole area and then create raised beds my concern is the lime only affects the top few centimetres of soil, which may mean during the creation of the raised beds I use soil which hasn't been touched by the lime.

If I create the raised beds first using compost or manure and then add lime to the tops of them, then the compost presumably counteracts the lime's effect.

Can anyone advise the best approach?

[suziequeue]

We are also on acidic heavy clay soil on a hillside in mid Wales and are going to build a load of raised beds but we are going to bring in a load of topsoil from elsewhere and concentrate the growing in that - liming as necessary.

Having said that - soft fruits love acidic soil and our blackcurrants are amazing. Blueberries do very well too.

[lachlanandmarcus]

To be honest, I was worried about the same issues with our acidic soil and manure making it more acidic, but I just chucked in a mix of the soil and well rotted manure and was amazed by the enormous healthy plants that grew. It was brilliant. Obviously ideally everything would be balanced but I would give it a go maybe with a sprinkle of lime. Manure does need to be well rotted tho, to avoid forking root veg and burning leafy things.

[ferretkeeper]

We too are on Wales' finest heavy acid soil (if you can call it that at just a few inches depth) over granite, halfway up a mountain!

Agree with the other comments...I'd make the raised beds now with whatever soil or compost or muck you have to hand; if there's a lot of clay by all means use some lime to help break it down as well as grit and/or sand to open up the texture, but as you say if you add a lot of compost it might cancel out any effect.

I'd also suggest using a green manure to see you through the winter, maybe Alsike clover, winter tares, hungarian grazing rye, phacelia, or winter field beans - some like the grazing rye or phacelia will fit in anywhere in a rotation, others you need to work in with the legumes and they won't be fixing much nitrogen over winter so limited benefit there.

Alternatively something with a good tap root might go into the original soil layer and bring up nutrients that way, comfrey or lupins spring to mind, and spuds are good for breaking up new ground...

I reckon check the pH again in the new year/spring time and go from there - if you need to add lime for particular crops do it then as per the rotation. Otherwise go with nature and let the plants that thrive here do their thing!

Not sure where you are exactly but Carmarthen council have a recycling place where you can buy their compost in bulk - I got a 10 tonne lorry to drop off some topsoil for our massive raised beds (got bored trying to do it by trailer load!) and asked if he'd go and get me the same of compost, and he did indeed, very cost effective!