Gardens with Tree Root Intrusions

[karstopography]

One recent thread someone, cannot remember who, mentioned gardening with tree roots coming into the space where they grow vegetables.

That fact that at least some of us, including myself, have to contend with the perennial issues of tree roots coming into vegetable garden, I thought I might start a thread to discuss the potential tips and pitfalls of sharing garden spaces with tree roots.

First tip I’ve found is that beans, garlic and onions really don’t mind so much having to share some of their rooting space with tree roots. That these crops are viable in areas prone to tree roots.

[worth1]

I have cedar elem in my yard and they suck water like no tomorrow.
They create a hairball of roots wherever they are.
You can't do anything once they take over.
Both my raised beds are ruined.
I'll never put a raised bed in again without it being on a concrete slab.

[bower]

I'm very familiar with this problem as well. There are large conifers all around my garden but the real root issues are happening on the north side which is, of course, the sunny side. So crops like garlic, or wheat, which really need full sunshine or they won't produce, have to face the challenge of tree roots. Conifer roots also became very finely branched in a raised bed and sucking away nutrients and water from the crop. It was not good for garlic in my experience. I had a bed that was constantly invaded and had to double dig every second season before planting garlic. Roots that invaded during that season were accompanied by smaller bulbs, that's for sure. In the last cycle I decided to make the bed narrower and longer in order to move it another foot and a half away from the treeline. Did not get any roots with the garlic that season, but girding to dig the bed now before garlic planting time.
Winter wheat and perennial wheat were in that bed this summer. I didn't see any sign that they were bothered by roots, but maybe there are none? I'll see.
OTOH there's a pin cherry tree south of and close to a bed on the other side of the house East. It definitely shades the lower part of that raised bed, and that was not as bad for garlic this year as it was for spring wheat the season before. I see that as another problem. But these roots can be very invasive, and took years for me to clear pin cherry sprouts from deep bits of root in another bed. With this bed, well yes, there's another layer of bed prep when you have to dig deep to make sure nobody's home before planting. I did cut two conifers that were too close. Wouldn't be surprised to find cherry roots in the upper part of this bed, as it did really poorly this summer and was always too dry no matter how much I watered.

So this is a really good discussion to have. I'm very interested to hear about strategies for managing tree roots.

[karstopography]

Most my beds are getting live or water oak root intrusions. I tear the roots out with my garden fork and occasionally a shovel when I’m doing fall plantings and then again in the Spring. The newest beds are now getting bald cypress roots.

It’s a good workout getting those either one of the roots out. I like revving up the heart rate once in a while and root removal is a top notch activity for that.

I did notice the tree roots put odd shaped grooves in some of my potato tubers last spring. Didn’t otherwise harm the tubers, just put root shaped grooves in them. I plant my potatoes in a bed located most under the tree canopy. That area gets good lower angle sun from February into April, just when the potatoes are really growing.

Cypress roots travel many, many feet beyond the tree in search for water. There are large cypress roots breaking the surface of the soil by our back porch 70 or more feet from the nearest cypress tree.

The cypress roots had invaded one peanut bed. Those peanuts got planted May 2nd and harvested this September. In May, there were no cypress roots. I can’t see how the roots hurt the peanuts, though, those peanuts seemed to have been more productive than the other non-cypress root affected peanut planted raised bed.

[worth1]

I've had cedar elm roots come out of the ground crawl over a container about an inch and back into it.
It kept the water sucked out of it and it didn't have drain holes.
Cedar elms are a nightmare.

[MissS]

I used to own a home that had a septic field and I use a tree root preventative product to keep the roots from damaging the tank and field. I wonder if something like that could be used as a barrier around the outside of the gardens too? I just looked and all I can find are products to add to your plumbing pipes. I wonder what the active ingredient in that was?

[eyolf]

I have a wild plum relatively near one side of the garden. Apparently they are able to send runners at least 100 feet in service of forming a thicket.

Damn things.

We harvested 55# of plums from it, and neighbors got at least as much. Plum jelly, plum jam, and plum wine.

It's provenance is very likely rotten/bruised plums thrown in the chicken yard 30 years ago. The hens still eagerly anticipate the ones that drop into the chicken yard.

[karstopography]

I used to own a home that had a septic field and I use a tree root preventative product to keep the roots from damaging the tank and field. I wonder if something like that could be used as a barrier around the outside of the gardens too? I just looked and all I can find are products to add to your plumbing pipes. I wonder what the active ingredient in that was?

Copper sulfate is one compound used to kill roots in septic lines. Rock salt is another. I’m not sure how to keep either of those away from the vegetables so as not to kill them along with the tree roots or the grass on the lawn.

[rxkeith]

dealing with tree roots, i think it is better to have a smaller garden area where the roots are a problem.
maple trees, in particular silver maple trees have an extensive, and many shallow roots system. we had to replace a sewer
line at our house in lower michigan that the previous owners did not deal with. i was insistent on having a garden even though
the owner said forget about a garden on account of all the trees. the maples on three sides were fifty-sxty ft tall.
we did a 12 x 12ft garden. you never saw a more extensive mat of roots in your life. large roots had to be chopped out. then there
were all those small feeder roots. it was one of those projects that if you had known how much work was involved at the time, you
would have never started it. but, i was going to have a garden. the garden did fine. one year we had basil that grew like a shrub. never
had basil grow that large ever since. regular maintenance is going to be important. a good sharp flat blade shovel can be used around
the outer perimeter to keep infringing roots at bay. once i knew we could grow a garden, i started making it a little bigger each year.
you just have to do a decent job of getting the roots out to begin with, and keeping them out on a regular basis. i think.

if you could have sucked all the dirt out of that 12 x 12 area, leaving just roots, you could have spread out a blanket roll, and slept
on top of it like a mattress. thats what i had to deal with.



keith

[bower]

Digging out roots is certainly good exercise.
One thing I was doing with the raised beds was to dig down as deeply as possible, line the bottom with heavy cardboard or birch bark and then backfill before planting the garlic. The wooden bed frame also served as a barrier of sorts for the shallowest root approach.
Lining the bed bottom did slow down the incursion of roots, but was a really big job to do every season.

[karstopography]

I dug out a few roots this morning. My 3.5 x 6.5’ box really does not get tree roots being as far from the trees as any of the boxes. That’s where I put my fall direct seeded summer squash, seeded this morning after turning over the soil with the fork one more time. Fertilizer is Crab meal and feather meal. I’ll add something with potassium later.

The 8 x 10’ bed where the cucumbers went had a few roots, not too bad, it too is pretty distant from the oaks.