Advice please do i double dig clay for raised beds

[furball]

I have got some scaffold boards for raised beds. I have to dig up lawn and i know under the top soil i have clay, do i need to double dig or will that just fetch the clay to the surface. I have also read that you shouldn't double dig as it can disturb the balance of the soil. What do you recommend please. Oh don't know if it makes a difference but this bed is for potatoes. Thankyou

[shirlthegirl43]

The whole point of raised beds is usually to avoid digging. I did spuds in a new raised bed last year and just left the lawn, spread some well rotted manure on top and placed my spuds on that. I then covered with a layer of multi purpose compost (I have no depth of topsoil in that area) and then 'earthed up' with lawn mowings and more multi purpose compost.

It is getting a bit late in the season for planting spuds outdoors though

[furball]

Shirl you are a lifesaver, just dug a test hole to check how near the surface our drainage pipes are and got down 8 inch, 1 inch topsopl, 7 inch cinders and thats before i get to the clay. House is 88 years old and i think that the back garden was used as the dumping ground for the coal fire. So no digging sounds great, thankyou.

[teakdesk]

Oh don't know if it makes a difference but this bed is for potatoes. Thankyou

...but presumably the bed will be used for something different after potatoes?? Crop rotation?


I have similar soil to what you describe... when my pond was dug the clay was still solid at 5 feet depth. If I double dug into that it would just create an underground pond... a great reservoir of water for deep rooted plants in dry times but could rot roots in normal times!

For me it depends how your water runs off; I would dig the lawn over down to the clay and then leave anything beneath. My raised beds were designed to increase drainage which has been done by the continual addition of compost and sand to the soil in the raised parts with the heavier original soil underneath holding enough water for dry times.

Potatoes are often recommended for new beds because traditionally you need to dig the bed to make trenches and then dig the soil over to find the potatoes - the plants themselves don't turn the soil over (there are no-dig methods that make potato growing easier but which don't turn the soil over).


EDIT: I typed that reply too slowly!!!!

I'd do it as Shirley says. Can you double up the scaffold boards to give a really good depth of soil - you don't have to fill it all now? If you only have an inch of soil now then I'd try to add a depth of compost before putting spuds down in the no-dig way.

[furball]

Thankyou Teakdesk, 5ft solid clay OMG. The garden is on a slight slope so with that and the cinders will i be ok for drainage?

[teakdesk]

If your existing lawn doesn't flood when it rains then your drainage is fine now and won't change with raised beds on top of it.

Good luck!!

[furball]

Great, will leave the posts long enough so i can raise the sides of the bed.(s) Thanks again for the replies. potters along to find out which lates to plant, hmm decisions decisions

[teakdesk]

...potters along to find out which lates to plant, hmm decisions decisions

If you mean which late potatoes to plant then I'd council for planting earlies.

The "early, second early and maincrop (lates)" refer to harvest times not planting times - in fact all potatoes are planted at about the same time.

Earlies/second earlies planted now may have a chance of maturing before the season ends but maincrop will not.

[furball]

If you mean which late potatoes to plant then I'd council for planting earlies.

The "early, second early and maincrop (lates)" refer to harvest times not planting times - in fact all potatoes are planted at about the same time.

Earlies/second earlies planted now may have a chance of maturing before the season ends but maincrop will not.

OOps you would never guess i'm a newbie would you I just want some potatoes for christmas, any recommendations gratefully received. (thakyou)