Clay soil remediation: I need some gardening advice....

COWLOVINGIRL

Hey everybody!

So,

I have a long bed in my gardening that currently has weeds and raspberry plants in it. I want to turn it into a huge potato patch but the soil is all clay. Any sugestions on how to improve it enough to grow a ton of potatoes? Thank you in advance!

JodieDownUnder

I think you could go a couple of different ways with this. Weed the garden bed, spread a good few handfuls of gypsum(helps break up clay) add some compost fork it through, plant and mulch. Option 2, weed garden bed, put down layer of compost, place potatoes in compost and mulch with hay/straw etc everytime you see the green tops appear, apply more mulch. Alternatively if you type in potatoes in the search box up in the right hand corner of this page, you will find some great ideas re growing spuds (aussie slang for potatoes ) recently I read a great article on growing spuds in timber boxes with very little soil and appeared to work a treat.

Just remember with your clay problem, gypsum and plenty of organic matter. Good luck.

Paradox

I can relate to this! We have solid clay below about 4-10" of top soil. I think covering the soil (cardboard or something similar that will provide a barrier but breakdown over time), then build up--compost, Coir or peat, even woodchips. But something that will stay reasonably loose.

Good luck!

COWLOVINGIRL

Thanks so much guys! I think I'm going to go with option #1jodienancarrow! And I didn't know that gypsum is good for working with clay, so thanks! And that's a really good idea Christa, about the cardboard! I think I'll do that too.

blevinandwomba

Here to commiserate on the clay! Some areas of my yard are more of a loamy clay, and others almost pure clay.

Ditto what @jodienancarrow already said. Also, lime is supposed to help particulate clay( ooh, I used a big word), but is not good idea if your soil is alkaline. I've been using lime a fair amount this year- we'll see how it goes.

A good garden fork can be a a lifesaver, but remember not to work it when wet! That last rule is such a pain, because it can stay wet so long, but the first time your turn a spot into a pile of clay "rocks", you'll see why.

One end of my garden has particularly dense clay, and has some shade. I finally planted tomatoes in it yesterday, but I tried for two weeks for a day when the soil was dry enough there. About the time I thought I could, it would rain again.

Lisa K

One nice thing about potatoes is that you do not have to have great soil in fact you can dig a hole or even use a bucket with 2-3" soil and cover it with leaves.

Torey

@Lisa K You should check out the ph of your soil before you start. Easy to do with a piece of litmus paper. My soil is very alkaline so adding gypsum wouldn't help for me. I add a bit of peat in with compost as it is more acidic. Particularly for the more acidic loving plants like blueberries. Helps to "fluff" up the soil. I have relatives living in another climate that is very acidic so they add gypsum or lime to their gardens.

COWLOVINGIRL

Thank you torey! Where would I get litmus paper? Is it something that you order online?

Torey

@COWLOVINGIRL Most garden centres will have a ph kit but that can be quite expensive. Most drug stores will have the litmus paper by itself, not as part of a kit. But you can also get strips at Walmart or online at Amazon.

By the way, welcome to the forum, if no one has already said that. This is a great place to learn from others or offer your special knowledge to everyone else.

COWLOVINGIRL

Thanks so much torey! I'm definately going to look into those!

Megan Venturella

It sounds like you already have great answers, but I wanted to add that I have hard clay and patchy lawn, and I just put potatoes down and put 6-8 inches of dirt from the chicken area over it all. I did it last March and the plants look great. I haven't done any hilling up or mulching beyond that. If you have any animals, old wood chips, or lots of compost this is an option.

COWLOVINGIRL

Thank you Megan!

chimboodle04

I know you have your potato answer - those potatoes in and of themselves will really help to break up that soil :) I wanted to add that after you harvest them, consider sowing a later cover crop to help enrich the soil for the future - diakon radish springs to mind. It will grow quickly and drill down into that clay even further to help aerate it. Leave it there all winter to die off naturally and the decomposing roots will not only add nutrients to the soil, they will also attract more beneficial soil organisms to the bed :)

COWLOVINGIRL

Thank you chimboodle04! That is so cool you say that because I have recently been learning about cover crops, and I think they are so cool! Before about six months ago I did't realize they existed! I can't wait to try using them! DO you recommend a source?

shaley1357

I just harvested potatoes from a 4'X4" Ruth Stout style bed and a Potato Tower. The Ruth Stout bed used 9 seed potatoes, a little compost a 2 large bags of left over fall leaves I haven't composted yet. I harvested 25 lbs of potatoes from that bed. The potato tower was lined with pine straw I had around and filled with compost. I planted 5 layers, 5 seed potatoes per layer. I harvested about 25 lbs of potatoes from each tower. So I'll be going with the Ruth Stout bed in the future.

And yes, the Ruth Stout bed can be planted right on top of your clay. THe compost and leaves/hay can be worked into the soil after harvest of left on top as a lasagna bed.

chimboodle04

@COWLOVINGIRL I got my seeds from baker creek - the ones I planted actually had time to set seed as well so I collected it to sow again later - bonus! Cover crops were such an ah-ha moment for me too! :)

MaryRowe

Just came across this article about dealing with clay soils that I thought was particularly good.....

https://today.oregonstate.edu/news/diamonds-clay-soils-are-forever?utm_campaign=Gardening%20Newsletter&utm_medium=email&_hsmi=203688898&_hsenc=p2ANqtz-8hidzlLbvk16tF3F20cnK8_4Q0HznSVABD7Dlik7afa8hm3--vObGspreveGjBBMCuYaYRPiFycBM9Uiw8ITZv0UGB8A&utm_content=203688897&utm_source=hs_email

COWLOVINGIRL

Thank you @MaryRowe! I going to check it out right now!

VermontCathy

Clay soil is a problem that a lot of us struggle to overcome. It can be very fertile and it resists drying out during droughts, but you need to add a lot of organic material to it to make it grow much.

I plan to experiment with adding large quantities of peat moss and compost and mixing it thoroughly. Other options include some kind of hugelkultur or terra preta. Last year I put in a sort of mini-hugelkultur bed with a lot of partially-decayed small pieces of wood and leaves on a clay bed where I dug up and turned over the clay, breaking up the chunks as much as possible.

We'll see how that looks this spring after the snow melts.

MissPatricia

I would think adding sand would help; peat moss mixed with the sand will help. If you have or can get wood chips, add them on top. They make a good mulch and as they decompose, they improve the soil.

vickeym

Will be watching and hoping to try all kinds of information for clay soils. I am clearing some new area once the snow melts from the area we plan to clear for gardening. We have very heavy clay soil here with a small layer of topsoil and under the two of them is hard packed gravel.

So lots of work to be done to create a large amount of good gardening soil.

VermontCathy

@MissPatricia Someone on TGN warned me not to add sand to clay soil. Apparently it has potential to make the soil even harder and more concrete-like.

I have decided to completely redo the flower garden a previous property owner put in my back yard. He apparently put down a sheet of black plastic on the clay, piled good soil from some unknown source on top, and planted bulbs and annual flowers plus a couple of rhododendron.

It looked great when we bought it, but it is extremely difficult to keep weeded, so weeds have taken much of it over. Even a few small trees have managed to get started there despite my efforts to cut them back.

So the plan is to dig up all the bulbs, remove the black plastic, dig the clay down at least a few inches, and add a lot of peat, compost, vermiculite, and leaf mold. Then replant the bulbs and add the desired annuals, focusing on useful herbs and flowers.

It's a big project and can't be done all at once. And right now it's 90F, so I'm done working outside for the day!

Merin Porter

https://community.thegrownetwork.com/discussion/comment/862351#Comment_862351

@chimboodle04 I had looked into planting daikon radishes and just letting them rot overwinter as a way to amend my soil, but then I started doing more research and people were saying they really stink when they rot. Have you ever done this with them? Do you have any first-hand experience with the smell?

MissPatricia

Thank you, Vermont Cathy. What I did was make the soil mixture and put it on top, but now I am using hugelkulture so it is just the top layer in the raised bed. I don't know if that will be a problem at the ground level; I did not use plastic beneath the raised bed.