Hard clay soil

I have moved to a new property this year (97 acres of mostly forest) and was told by the most recent owners that an old overgrown area was a garden several years ago by the original owners of the property. I wrongly assumed that the soil must be good or workable in this area. Our property is on lots of rock. Most places you put a shovel in, you hit rock a few inches down. It really is a wonder when I see the amount of brush and trees on the property that seem to flourish in such conditions.
We attempted to start hand clearing this old garden in the summer, but were overcome with ticks and bugs, so put off clearing it until the fall. We hired someone to come in and bush hog this area. This "old garden" is in a low-lying area somewhat close to the house and is starts 30-35' from the top of an artificially raised septic field. The lids for the septic tank are maybe 50' away from the start of the gardens (and it goes back another 50').
The septic field gently slops down into the old garden area. We have also discovered that even after a light rainfall, there is lots of sitting water. The water table is very high in parts of this area - so much so that a 2' hole fills up with water and doesn't drain after days.

Am I crazy to attempt to garden in such close proximity to a septic field?  The more workable area appears to be the closest to the septic field.

We have considered raised hügelkultur mounds or raised beds constructed from wood or steel but even then we may not be able to access these gardens during wet periods if the area around them is sopping wet.
The idea of raising and amending this land (60 x 100?) over a period of years seems daunting and I am feeling very beaten by my environment.
Am I missing anything in my assessment of this area? Should I just give up and look for other areas? It sure seems like we are stuck with raised beds due to the heavy rock on our land. Is there any way of planting a fruit tree in a raised bed?

my land is very similar. i grow in raised beds and they do well. all my trees are in 4'x4' raised beds as well. what do you want to plant there? currants , elderberry, aronia and serviceberry grow great in clay soil. these i grow in ground here. you can lay old planks or lay branches in between the beds when there's standing water or put some crushed rook down every 3-4 years instead. even in the beds make sure you have a good draining soil mix in there with lots of perlite. they should be at least 16in high with 24'' the best. also if you can dig shallow trenches from that area going downhill to drain some of that water off, do it. good luck.

To me, it would be wise to look at another area to have your garden.

From your description, the soil may have been depleted of minerals needed, standing water, and then there is the risk of "the septic field gently slops down into the old garden area."

I live where it is very rocky so we made raised beds by combining "leaf mold" found on our property under trees, bought soil, well-aged manure, and some clay from our property.

The problem with trying to plant fruit trees into a raised bed is that the roots will still have problems hitting rocks below the raised beds.

We dug large holes, then added lots of organic matter, and the fruit trees we planted just never did well.

Maybe others will offer some better solution than I have been able to.

Cathy, I sympathize with your clay issues.  I have them too, but not to your degree.

My personal thought is that a raised bed is almost always worth the effort, but I am obsessive about these things.  It is more upfront work, but it is more productive in the long run.  It is also easier to make these beds in such a fashion that they are easy to plant, harvest and tend.  The garden bedding itself can be be made extremely fertile, tailored to your individual need.

As far as the fruit tree, I just don’t know if a tree has the same contamination issues as a green plant.  Usually the issue was greens on septic fields is tiny bits of fecal material accidentally getting splashed backed onto the leaves.  I don’t think this particular issue would happen on a tree.  I may be mistaken, I have often wondered about this issue.  I don’t blame you for being this concerned, but maybe someone else here can chime in who knows better.

I DO know that there can be issues where the tree damages the septic field by having the roots grow into the pipes in the field and clogging them.

It is possible to grow a dwarf tree in a large container such as a half-whiskey barrel.  Just make certain it does not dry out!

So I wish I had better news about the septic field, but I do strongly encourage building the raised bed/hugel mounds.

Eric

Anne Miller wrote:To me, it would be wise to look at another area to have your garden.

From your description, the soil may have been depleted of minerals needed, standing water, and then there is the risk of "the septic field gently slops down into the old garden area."

I live where it is very rocky so we made raised beds by combining "leaf mold" found on our property under trees, bought soil, well-aged manure, and some clay from our property.

The problem with trying to plant fruit trees into a raised bed is that the roots will still have problems hitting rocks below the raised beds.

We dug large holes, then added lots of organic matter, and the fruit trees we planted just never did well.

Maybe others will offer some better solution than I have been able to.

i havent had that issue on my rocky, clay soil. i just put down cardboard, drive a 5ft stake through the center of cardboard, place my raised bed, place the tree roots on cardboard, tie tree to stake, mound with good draining soil, tamp, then mulch with 3in. woodchips. i have about 70 trees/ bushes planted this way and all are growing well with no care. ive even done it without the raised bed with good luck.

Plain old baking soda can floculate the soil, making particles separate more so it is tillable.  Just toss it around same as liming a field.  Clay needs some gypsum too, to soften it up, and lots of organic matter worked in.  Wheat straw and leaves are good.  

Thank you all for your responses to my post. You've given me some things to consider. We already have raised beds, but it looks like a lot more are in our future.

Hi Cathy,
It seems like you have several issues with that spot.

Downhill from a septic system - If the septic system is working properly, then this distance is fine. But you do run the chance that the system might have issues and you could potentially get some bacteria downhill that you don't want. This is one of those... probably not a big deal, but if you want to be extra careful, then maybe only plant things that grow above ground and don't contact the ground.

Standing Water/Heavy Clay - It sounds like this is in a mini valley with poor drainage. Here are a few thoughts.
- You could rent an excavator, dig it deeper, and make a pond. Add reeds, cattails, etc for extra filtration and maybe some water plants to feed livestock if livestock is on your radar. I'd add some fish for mosquito control... but I might be leery to put fish in it for eating, since it is downhill from the septic... again, probably not an issue, but better safe than sorry.
- A slow, but more natural option would be to cover the area in about 6-10 inches of wood chips (bonus if you put fall leaves down first). Then let it sit for a year. While this is a very slow process, I think you would be amazed at what the soil looks like after just a year being covered in wood chips. The wood chips breaking down will attract bugs and worms and various microorganisms and fungus. All of this will help break up the soil. The extra organic matter will aid in water absorption, and I would be surprised if just doing this didn't take away most of the standing water problem. It would also loosen things up for planting down the road. Just remember to pull back the chips and plant in the soil.
- A faster way to get part way there would be to rent a large rototiller. Till it as deeply as it will go. Pick out all the good sized rocks that you can. Then go get enough mostly composted cow manure (preferably organic) to cover the garden area in at least 6 inches. You can use fresh manure, but it is harder to mix in if its still wet and sticky and also takes longer to break down before you would want to plant. Till that into the garden as well. Cover it in a few inches of woodchips or straw or some sort of organic mulch. Let this sit for a couple months. Both this option and the just wood chips will add organic matter and loosen the soil. These are things you need when dealing with heavy clay soil and standing water.

Good luck, let us know how it goes.

Cathy Fleischmann wrote:I have moved to a new property this year (97 acres of mostly forest)...

Am I missing anything in my assessment of this area?

I'm on very hard clay and the 97 acres of mostly forest caught my eye. I would highly recommend that you visit this forum: https://permies.com/f/190/biochar and learn how to make a bunch of biochar out of any dead wood in that forest that hasn't gone punky (keep the punky stuff for filling your raised beds/hugels!)  I have found that biochar, particularly chunkier than the perfect small size, is great for lightening up my clay soil, while still holding nutrients and helping my growies.

That said, over a bunch of my clay soil, I have built some 30" high raised beds, but that's partly because I'm a "senior" and don't bend as well as I used to.

I would also be somewhat concerned about veggie gardening near down hill from a septic system. Personally, I wouldn't worry about fruit from trees, and I've had such locations recommended for coppiced firewood or other woody products such as for basket weaving. As mentioned, yes, plant far enough below the system that roots infiltrating won't be an issue.

On a small scale (1/4 acre) I have been treating my garden of heavy clay with the products of my bunny.  I keep indoor house-bunnies as pets and use compressed wood pellets as bedding/litter.  It expands with urine and certainly the poop doesn't hurt the soil's fertility!  The litter itself does a huge service, however.  Since it breaks down to sawdust, it fluffs up the clay soil.  I've been doing this for 15 years and my soil is now lovely!  It does a faster Hugel-sort of action.  Holds nutrients in the soil, gives the worms space to move and makes things easier to work.  I daresay if working on a larger scale like you are, it might be worth having more than 2 bunnies at a time!

We have a full complement of clay soil apprx 1.5ft down from the surface throughout our 25 acres.  

Digging ponds, perimeter ditches works very well.  Solar operated pond fountains help with aeration and bug control.

Then lots of woodchips, soiled ivestock bedding of all kinds.

We also have made inroads with local grocery stores to pick up their waste produce and bakery goods for our livestock.  Along with it comes spoiled citrus fruits, onions, radishes, potatoes etc which are of no use to any kind of animal or human..they all go into an ever growing compost pile which becomes perfect "fill" in the spring for raised garden beds.

We mill our own wood, so imperfect live edge and outside rounds and boards make perfect holding walls for our raised beds...just pound a few wooden stakes in here and there to hold the boards ..so easy the kids can it.  By the time these boards rot down, they'll probably be buried in beautiful soil that has been created in them.

Or once the raised bed is full, or overflowing take out the boards and wooden stakes and set them into the next area waiting for it's turn.

Good Luck with it!  

I would be more concerned about the low-lying location and any leach lines that handle overflow from the septic tank, especially if there is also standing water.

Even a purist who uses soapnut soap in the laundry and never uses any chemicals in cleaning the kitchen/bathrooms could be up against very alkaline water from laundry, baths (absolutely no deodorant soap,) going into that septic tank, which will eventually leach out into the garden.  Tomato roots often go 5 feet deep when they are happy.  So how many decades has that soil had the leach lines going into it with all kinds of kitchen/bathroom chemicals?  Buckets of Mr. Clean from mopping the floor, Comet cleanser,  hair shampoo, hair conditioner, shaving cream...

I have clay and love it.  It is only a problem when it dries out, so it should never be exposed to the sun.  Thick, thick organic mulch 4-6 inches to start, or 3 inches of wood chips (as opposed to bark chips) maintained at those depths will keep it workable and great.  It's high in minerals which improves the nutrition of anything you grow in it.  It holds more water so you don't have to water it as much as long as it is mulched thickly.  

Have you looked into the Back to Eden wood chip method?  It's not only good for the soil and soil critters, it's great with clay.  No till, and the fungi start forming quickly, worms come up into the soil quickly and do the tilling for you.   You may not even have to water it much at all if you get summer rain.   It also gives a thick cover on pathways so walking in damp/wet won't stick to your shoes.  And if there's heavy rain, it protects the soil from that as well.

Keeping the garden close to the house will make it easier to be in in.  Permaculture Zone 2 or so?  Put it where you can admire it from the house, out of the wind as much as possible.  

I am in agreement with Cristo Balete-

"I have clay and love it.  It is only a problem when it dries out, so it should never be exposed to the sun.  Thick, thick organic mulch 4-6 inches to start, or 3 inches of wood chips (as opposed to bark chips) maintained at those depths will keep it workable and great.  It's high in minerals which improves the nutrition of anything you grow in it.  It holds more water so you don't have to water it as much as long as it is mulched thickly. "

My thoughts are..
Compost. Compost. Compost.
Mulch....mulch....much. Work organic materials into beds whenever possible...
Fork over areas before doing anything on top, like a modest raised bed or hugelkultur....
By forking the area (gently rocking the fork once inserted, and not turning.... just loosening the earth) you will effectively double your topsoil later, gaining more water and air penetration, and giving your plant roots a chance to do the real work of creating soil that is to their liking with the help of their friendly little bacterial and fungal friends.
Anything you can do to promote the presence of fungi, such as adding FOREST (partially or fully decomposed) LEAF LITTER to your compost or beds. This will promote aerobic conditions in the beds. Your enemy with clay is anaerobic conditions which strengthen the bad guys and weaken or kill your plants...
I think the proximity to septic could work either way. I know a very respectible plum tree that adores it's spot right by the septic.
The key would be to ditch conventional soap products throughout the home in favour of naturals like vinegar and baking soda (laundry). There will be threads on this somewhere.
Lastly.. I personally would recommend working with the biodynamic preparations, especially Preparation 500 in spring and fall. This alone could make a tremendous difference.
I think you have an opportunity here if you like the site and it has great access.
Hugshugs from late springtime new zealand where the garden is drying out after a plethora of rain, and several baby birds are hanging out hoping for the Miracle of Flight to suddenly happen.

Howdy!
I hope, after hearing from all the wonderful and helpful people earlier, that you have made a few decisions about your garden area.
It comes down to - really think if that's where you want to be, garden-wise.
                                If that's where you think a good garden location will be, then add All The Organic Matter. All of It.
                                Just Keep Adding Organic Matter.

Of course, that seems to be the Permie way. Want a garden? Add Organic Matter.
And it's right, in my experience. All soil needs More Organic Matter, however you get there.

As far as I can see, the septic system is only a problem if you let it be one. There are a few concerns (fecal bacteria, acidity from years of leachate, random chemicals having been dumped) but there are also lots of solutions available, depending on what your soil tests tell you is going on.
Raised beds are a very good idea, in a general way. The soil warms up faster, there's better drainage (which sounds like a concern), you have better control over what the primary makeup of the topsoil contains.
Really, clay only matters as far as drainage, and then only in the amount of work you have to do. It is full of all kinds of wonderful things and plants love it, as long as they don't drown or dry out.

So, put some thought into other areas close to your home, then pile up All The Organic Matter and run with it. While we all like to think that our initial garden locations are permanent, if you view that first year's garden as an experiment, you'll be better prepared for the alterations in your plan that will, inevitably, happen. If you have good sun exposure in multiple spots, maybe try smaller gardens in each spot. Or other fun and easy things. If you're just moving out there, you have a long list of Things That Need Doing, so ... give yourselves a break. This is something you can put in over time, as you get to know the land you are now partnered with.

These first few years are for getting to know more about your new land. Experiment. Play with ideas.
Be willing to change your mind, but once you make your decision, Add All The Organic Matter.
(Speaking as someone who lives in a river's water shed, on beautiful clay soil, and has 20 years in the same space of adding All The Organic Matter, and a fancy septic system as legislated by my county.)
Best of all thoughts towards the future of your new home!

Since you don’t know what was flushed down that septic for years, I too would be leery of any food grown downhill. Trees do uptake various chemicals. Never mind just the yuck factor. I hope with your acreage there are various sites that may work. Do that whole watch-for-a-year. Watch the sun pattern, the wind pattern, where all the soggy patches are, the frost pockets etc. Walk the land. That also gives you time (over the year) to look for local resources such as goats to rent for clearing the underbrush. Sure, stick a few favorites in the ground here & there, but take the first year “I gotta get the garden in - - (and the shed and the driveway and the and the chicken coop and the rabbit hutch and paint the porch and those window blankets and and and )” pressure off yourself. Gardens are a place off joy!

Lots of great comments and suggestions here. Anything mentioned will help evolve the soil beyond its current state but I'd like to add one more for clay, rocky ground.

A ripper shank pulled behind a tractor.

20" or so is the length of mine and it's a single shank design that breaks into the hard layers below, allowing the good stuff you spread on top to penetrate. It also gives a super highway for roots to now take over and dive deep, along with pulling up large horizontal laying rocks (which I then remove with the loader or backhoe mounted on the tractor) and basically any standing water that once was in the area now has deep channels to drain and seep and spread into.

It's something that can basically be done once and never again, ideally with a no-till bed established over top the original rip line(s). I have only been practicing this for 1 year so I don't have long term results, but the technique of a deep rip ON CONTOUR (pretty important) has been around for a while and used by Mark Shepard from his research on P.A. Yeoman.