I have a large back yard but it has issues of course, that's my luck... We had a few very large trees that we cut, opened up some sun and space, but the roots are of course still running all through the ground. Elm and Silver Maple. I also have a septic tank smack in the middle of the yard, right at a focal point... I don't know where the drain lines run, but as with my luck I am pretty sure they are under where I HAVE to put the garden. The yard is deep but rather narrow and we have a well/propane tank and a driveway and will be adding an outbuilding, so there just isn't anywhere else to put it where it will have access to a water hose. The soil seems good, but just too packed and hard to use. I cant' till it because of all the roots. So I was thinking of adding raised beds. Can I put raised beds over the leach field of my septic? And how deep should the beds be. I am worried that if they are too shallow the packed soil underneath will prevent drainage? I don't think it is clay-like, just has been driven over a lot and that sort of thing. Any ideas?

@fiwit might know about the septic question

Sorry - I don't know enough. But contact your local county extension office. They should know. Or @Dave might have some ideas.

With that disclaimer, here are my thoughts. You need to find out exactly where the drains are. You don't want to put beds over the drains, because you don't want to dig them up in the future. And you don't want to plant anything like maples or willows anywhere near the septic field.

If your trees are anything like the bradford pear I took out, new trees will sprout from the roots, so you'll need to put some kind of root-killer in there, or just cut the sprouts every time you see them. As for access to a water hose -- buy a couple hundred-foot hoses and string them together, if that's what it takes to put the garden farther out.

Raised beds are always easier to work with, in my opinion. Don't worry about how hard-packed the underlying earth is -- if you build good raised beds, worms & other organisms will come to live there. I highly recommend starting with several layers of newspaper/corrugated cardboard, for two reasons. It makes a phenomenal weed-block, it decomposes and helps build up the soil, and worms love it (OK, that was 3 reasons). The more worms you have, the better your soil will be. That much I *do* know for fact.

See? I thought she would help.

I would think it is not a good idea because of the chemicals from different cleaners and bleaches could get into your vegetables.

Hmm, had not thought of that of course. I do not use a lot of cleaners and such, I am allergic to fragrances so I go easy on all that stuff. I guess I could start using only natural products to fix that problem if I needed to. I could call the county to see what they thought of putting raise beds over the area, but as far as locating the lines it would be pretty difficult without a lot of extensive digging. I assume they are are 18-24 inches deep for the frost line. The tank is rather old, but the inspector when we bought the house last spring, said it was good, we had some repairs made to it, and ok since then. Well the Elm rooted in it and caused it to back up a few times, we dug up the line from the tank to the house and discovered the roots and cleaned it up and cut that tree which was only 10 ft from the tank and was enormous.
fiwit, yes I agree about the worms. There aren't many here in the yard, I think it is packed too hard. I could hook hoses together to reach the other half of the property, but it slopes down hill from that point and would not be seen from the house. I also think it would get critters too much in the garden since it is farther from the house. What is the best way to locate the leach lines?
I plan on filling the beds with compost and topdressing with buffalo and camel manure. Can I use that? Just asking because one of the neighbors raises them and I have that available to me. I also thought about foregoing the edging around the perimeter and simply layering some fresh soil over the ground, sort of berm style. That would be great because I wouldn't have to buy any edging that way. But just wasn't sure it if would harm my leach field. I guess I could till some of the area that doesn't have the roots as thick, if the lines are 18 inches deep, tilling over the top 6 inches or so will not harm anything?

what a cool idea if you could do it--camel manure!

For your edibles, you could do those raised beds on legs. If you're at all handy, you could build your own. There is a really cool one shown in the Gardeners' Supply catalog. http://www.gardeners.com/Vegtr...

Frillylily said:Hmm, had not thought of that of course. I do not use a lot of cleaners and such, I am allergic to fragrances so I go easy on all that stuff. I guess I could start using only natural products to fix that problem if I needed to. I could call the county to see what they thought of putting raise beds over the area, but as far as locating the lines it would be pretty difficult without a lot of extensive digging. I assume they are are 18-24 inches deep for the frost line. The tank is rather old, but the inspector when we bought the house last spring, said it was good, we had some repairs made to it, and ok since then. Well the Elm rooted in it and caused it to back up a few times, we dug up the line from the tank to the house and discovered the roots and cleaned it up and cut that tree which was only 10 ft from the tank and was enormous.
fiwit, yes I agree about the worms. There aren't many here in the yard, I think it is packed too hard. I could hook hoses together to reach the other half of the property, but it slopes down hill from that point and would not be seen from the house. I also think it would get critters too much in the garden since it is farther from the house. What is the best way to locate the leach lines?
I plan on filling the beds with compost and topdressing with buffalo and camel manure. Can I use that? Just asking because one of the neighbors raises them and I have that available to me. I also thought about foregoing the edging around the perimeter and simply layering some fresh soil over the ground, sort of berm style. That would be great because I wouldn't have to buy any edging that way. But just wasn't sure it if would harm my leach field. I guess I could till some of the area that doesn't have the roots as thick, if the lines are 18 inches deep, tilling over the top 6 inches or so will not harm anything?

about.com says to plant trees at least 100ft away from the septic field. The big thing is to not direct rainwater into the septic field, and to plant stuff with shallow roots. Trust me, you do NOT want a saturated septic field. and everything I'm seeing online says do NOT plant veggies, for the very reasons NJBob mentioned.

I'm thinking raised beds on legs might be a brilliant idea.

hmm well I am in big trouble already then. I think the neighbors have trees closer than 100 ft to my septic lines. The lot is narrow and there are neighbors on both sides right next to us. I have mature oaks and hickory trees closer than 100 feet that are at the far end of my own property. There is no way in 1 million yrs my dh would cut them. We cut a silver maple and an elm that was covering the yard with surface roots. I have a sweet gum tree about 30 ft or so from the tank. I would like to keep it, I would like to cut it. Maybe I'll keep it, but it should probably go....well you see the dilemma there! I planted some maples this past summer, but considering I don't know for SURE where the lines are and can only guess at this point, I would say they are 50 ft from the lines, considering they get 30 ft wide, or in other words 15 ft wide on that side. There is no rain water running off to that area, in fact it is slightly a raised area. I say slightly, because you can't really tell, it is a gradual slope, not like on a hump or anything like that. If all I planted was a veggie or herb garden, I would think that would be shallow enough roots? I understand that when the rain field becomes saturated or clogged the water discharged has no where to go so the septic backs up into the house....a pretty bleak thought. I think that switching to natural soap products in the house should make the area safe for planting over, I will look that up and see what I find.

I have sweetgums fairly close to where I'm told my tank is (like, within 10 ft) -- don't worrya bout the sweetgum. And remember, take everything on the intarwebz with a grain of salt. You might call the company that services your septic tank and ask their advice. And DEFINITELY contact your local extension agent - this is why they're there.

Our poor septic tank and leach field are surrounded by lilac bushes, and there are three huge cottonwood trees in the same general vicinity. And the adjoining field (where I assume the leach lines are) is regularly flooded in the spring. We've lived here for 14 years, and so far, so good! But I think I'll know where to look for the culprit if we DO start having problems!

When we lived in OK they had tanks that sprayed the water back out over the yard after the septic tank is done with it. I think we should do that here, but no one around here has hardly hear of it. The only thing that concerned me was having to drop the bleach tablets in the last phase, I don't know what that does to the soil. But everyone's yards looked green and healthy where it sprayed out.

@ Woofie, it is my understanding that having tree roots in the leach field is a HUGE big deal. If they grow into the discharge pipes, which can spread out all over your yard quite a long ways depending on what you have, there is no way to tell where the clog IS. The only fix is to dig it up, maybe a lot of digging. Of course cutting the tree at that point is moot, because the roots are still physically blocking the lines--who knows where... So that is why we cut ours now and not later It was a large tree so I hated to see it go, but hey, more room for gardening, right?!

Well, we just had the big tree (actually, HUGE, not big) cut down that was closest to the leach field. Although, not because of the leach field, but because of concerns it might damage the house if something broke loose. We had noticed some rot, and the tree surgeon concurred that taking it out was probably the best course. Hated doing it, but as you say, more room for gardening! And more sunlight for my roses!

>> raised beds on legs

Another way to keep veggie roots out of leach fields is to lay down heavy plastic or other long-lasting root barriers before you collect soil and compost to lay on top.

Just plan for drainage if you lay plastic under your raised beds! It sounds as if you have some slope or grade to work with, so arrange the hard soil under your raised bed to slope down towards some slope or grade that will carry your bed's drainage to a part of the yard that won't puddle or flood.



Of course, a "plastic floor" under your raised bed prevents the root zone from growing deeper as the unimproved soil absorbs organics from the bed itself. But I have heard people online panic about roots (even vegetable roots) getting into drain lines. I don't believe everything I read online, but I also don't know enough to dismiss their concerns.

In the yard where I grew up, the ONLY place that the grass was green was right over the drain line. Green and lush there, brown all summer elsewhere. I always thought that would be a great place to put a garden! Deeply irrigated PLUS deep-fed with organic fertilizer.

If you don't have a dry season dry enough to show clearly where your leach field is, all I can think of is to ask the contractor who worked on it to give you a quote for finding out. When I was looking at real estate in NJ, proof of an adequate septic system was a very big deal, and anyone hoping to sell a house knew they had to have proof of meeting local codes and recent inspections.

Maybe a local realtor can tell you where to look for the original septic system plans that I assume must have been filed somewhere. The realtor who SOLD you the lot might not be the best one to ask, if they are like NJ realtors.

Once we asked two NJ realtors whether something they suggested was ethical. Their answer was "yes, it's legal". We couldn't make clear the concept of 'ethical" clear to them, but apparently they looked it up and discussed it after we left. The next day, they used the word "ethical" several times, boastfully, proud of having learned a new word even if it wasn't relevant to their usual daily business.

>> buy a couple hundred-foot hoses and string them together,

It might be cheaper or longer-lasting to buy a roll of 1/2" or 3/4" black polyethylene irrigation "mainline". You can leave that pressurized 24/7 if you want. I found a better price for 3/4" tubing at a local store (Steuber's Distributing) but you can buy irrigation tubing and connectors from places like Dripworks or even Home Depot.

1/2" - $14 / 100 feet 240 GPH = 4 GPM
3/4" - $31 / 100 feet 480 GPH = 8 GPM

I think it lasts forever if you don't puncture it, let it freeze solid, or expose it to harsh UV (that is, bury it or cover it with mulch). Once you lay the mainli8ne out into your backyard, you can add as many spigots as you want for just $3-5 each. Plus stick sprayers, spinners or dripline into the mainline and water from timers.

http://garden.org/ideas/view/R...

>> I plan on filling the beds with compost and topdressing with buffalo and camel manure.

I may be crazy, but I'm wondering if that might be TOO rich and organic. It would continue to decompose through the growing season and tend to subside so that the bed would lose depth each year.

I would be inclined to use no more than 50-75% compost plus manure, and make up the rest with screened soil, especially if I could find some sandy soil or even gritty sub-soil. I like my soil to have some grit for structure, to keep it "open" so water can drain out and air can diffuse in through open pores and channels.

Then I would top-dress or turn under 2-4"of compost and manure every year, or as much as would fit into the bed without overflowing.

It's cheap and easy to make 16" high walls with concrete paving stones stood on end, but 2-3 rows of cinder blocks are more stable and you'll never have to 'straighten them up".




I once saw concrete pavers that were 24" x 24", and lusted to make a REALLY deep raised bed, but didn't think I could get them home unbroken. or lift them unassisted! Probably really deep beds need wooden walls, even though that's more expensive and they don't last forever.

But if you have have hard clay soil, the idea of berms for raised bed walls might be perfect.

Just allow for drainage under the berm so you don't make a mud wallow! A slit trench filled with gravel and covered with filter cloth (under the berm and leading down-slope) is probably plenty, but this corrugated, perforated drainage pipe is very cheap and much lighter to carry than drainage gravel!

Quoting Rick: "In the yard where I grew up, the ONLY place that the grass was green was right over the drain line. Green and lush there, brown all summer elsewhere. I always thought that would be a great place to put a garden! Deeply irrigated PLUS deep-fed with organic fertilizer."

We had an area like that when we lived in deepest darkest Eastern Oregon, too. Our goats thought it was great and so did the bunnies. Um, but we seemed to end up with more dead and deformed babies than one would think normal. Soooo, I personally would be hesitant to plant veggies in that sort of spot.

We're gardening above ground in areas of our yard that are similar to yours, Frilly. Do you still have any of the cut tree wood handy, or has it been used or taken away? It makes a great natural (although probably temporary) lining for holding growing media. No digging in compacted soil is required. I used ornamental plants in mine, but some of those were peppers, and they did just great.

The thread "New addition to an existing bed" in Permaculture forum

RickCorey -lots of info, I will rea it over an over an soak it in.


Woofie, generally eformities or still births in animals is relate to a genetic mismatch... Sometimes if the female is bre to a ifferent male-problem fixe. Of course it coul also be only the female herself. Inbreeing of animals also oes that sometimes an I woul think with most farm animals it is har to always know who the Pops is!

I did not notice any area of the yard any greener than another over the last summer. We did get fairly ample rain though.
We bought the house the last day of May 2013. The house was built in 43 and has been added on and is a hodge podge house. A real fixer upper that a lot of do it yourselfers had no idea what they were doing, that or they were just too poor to do better and it was also a rental for 16 yrs at least. So we fell in love with the place because of the location and the 1.4 acre yard. We could tell the sewer had problems. The seller paid to have it located, (they didn't even know where the tank was) and also had it pumped out and the concrete tank was cracked, so that was repaired. There was also a clean-out and a riser added. At that point we bought the house, the inspector said he didn't see any other problems with the system. But the leach lines were never located, just an approximate area where one would assume they probably are.
I didn't think you could put weed barrier or plastic down over the leach field because wouldn't it keep the moisture from drying out properly from the leach lines?

Chelle, we got rid of all the wood asap. We have been pulling out all the old wood timbers and stumps and leaves ect. The yard has went for years with hardly any maintenance and the house has termites. The stumps in the yard have termites. If we lay out a piece of wood for a few days, there will be termites in it. The neighbor has termites too and has been treating them for several years. There were termites in some railroad ties even. We are just trying to keep it clean and disturbed regular and keep treating the house. I hope we eventually get rid of them. This are of the yard is far enough from the house I hope using some fresh treated timbers or railroad ties will be safe. I don't like the idea of using any chemical treated wood for vegetable/food beds, but I figure the amount leached into the soil and taken in by the plants will still be minimal compared to all the chemical sprays used by big producers. In other words the vegetables will still be safer than store bought. With the termite problems, I don't feel comfortable using any wood products that aren't treated.

I like the idea of doing sort of a berm style. I could simply add some raised dirt and then I wouldn't even have to use any edging at all for now. I just didn't know if it was a good idea to add soil OVER the leach field.

Be cautious of the removed elm trees, they will likely send up tons of new sprouts from both the stumps (if you still have them) and roots, and your skin may be sensitive to them. Best wishes to your project!