My Troubles with Landscape Cloth: Part 3

Just beyond the back gate, there is a gravel path with landscape fabric underneath. It is one of the first areas we did, and perhaps because we were smart enough to lay a good thick layer of gravel to protect the cloth, it has held up fairly well over the years.

Still, you can see plants creeping in on edges of the pathway and under the concrete bench.

Wanting something softer underfoot in the section of the garden where I have my raised beds, I chose to cover the landscape fabric with natural cedar mulch.

Unfortunately, mulch breaks down quickly making the area the perfect home for weeds.

And it is not just the weeds that are a problem. It's all the prolific self-seeders, like the forget-me-nots and the eggplant-colored geraniums, that I planted in the surrounding flowerbeds.

By mid-summer the forget-me nots and geraniums have self-seeded and the weeds have moved in. 

The result is that I have a real mess on my hands in July and August! I can't tell you how many hours I have spent trying to keep this mulched area weed-free this summer.

The only way I think you could get mulch to work as a covering for landscape cloth is to rake it all up and replace it periodically through the growing season.

Money was tight when we came to doing the gravel courtyard at the back of the garden. We had moved in the year before and already had replaced the furnace, the roof and all the eves troughs.

So when we went shopping for landscape fabric, we favoured price over quality.

Huge mistake!

Compounding the problem, we made the top layer of gravel far too thin.

In areas, like the one under the two boys, the fabric has failed utterly making it easy for the weeds to move in.

With the top layer of gravel removed, you can see 

clearly the sorry state of the cheap cloth underneath. 

We are now looking at the possibility of having to redo the whole area.

If we do decide to move forward next spring, we will have to rake back all the gravel, remove all the old cloth in its ratty state and then lay new cloth.

What a nightmare!

Landscape Cloth: Does it really work?

In my humble opinion, landscape cloth laid correctly deters weeds best in the first few after installation.

Then it wears and seeds take advantage of even the tinniest pin-sized holes.

Even if you rake your gravel routinely, debris quickly builds up on the surface and then breaks down forming the perfect growing medium for sallow rooted weeds like plantain.

The weed Plantain has moved into this area where crushed limestone and flagstone sit on top of landscape fabric.  Plantain (right) can easily withstand drought, so it is quite happy finding a home amongst the flagstones.

The Reasoning against using Landscape Cloth:

• It's not cheap. The rolls of good quality cloth (4' wide by 50' long) we've bought are $30-$40 a roll. Then add in the cost of the pins or fasteners you need to hold the cloth in place. Finally there is the cost of the pea gravel or other surface material to go on top.

• The descriptive name"cloth"or "fabric" makes it sound pretty benign, but in reality, landscape fabric it is a petroleum product. This is a disturbing fact that I learned only recently. I have always prided myself on the use of good organic practices. To think I have unwittingly installed a petroleum product, that could be leaching chemicals into my soil, is frankly horrifying.

• It is time consuming to install and even more time consuming to replace.

• But my number one reason against using landscape fabric is that it doesn't work all that well over the long haul. 

Alternatives to Using Landscape Cloth:

If knowing landscape fabric has a questionable chemical makeup and is a potentially ineffective weed barrier makes you hesitate to use it, what are the alternatives?

Sadly nothing seems to present itself. Corrugated cardboard or thick layers of newsprint are temporary weed blocks at their best.

Truth be told, I find myself in quite a quandary as to how to readdress the areas where we have used landscape fabric.

What to look for when buying Landscape Fabric:

How can you spot poor quality landscape cloth apart from price? It tends to be thin and almost transparent. The fabric weave is uneven. The cheap stuff is guaranteed for 10 years or less. 

Before you purchase this type of product, you have to ask yourself: do I really want to redo all this work ten years from now?

Most good quality landscape fabric has a 20 or 25 year guarantee. It's has a heavy weight and isn't at as transparent. Most importantly the weave has even, uniform quality.

The only drawback to this more dense fabric is that water seems to pass through it more slowly. When I removed the top layer of cedar mulch, I found moss growing on the surface of my landscape fabric.

How to Install Landscape Fabric:

If you are creating a pathway or courtyard, you will be covering the landscape fabric with another material like pea gravel. This top layer should be at least two or three inches in depth to both protect and hide the cloth underneath. To allow for the top covering, you therefore need to begin by digging out the project area to the proper depth.

Once the area is dug out, the ground must be levelled.

Next, prepare the area carefully removing any surface stones that might create holes in your landscape fabric.

Lay out the sections of your landscape fabric. Overlap pieces of fabric by at least 8". (In the how-to article referenced at the end of the post, they actually recommend a full 12" overlap.)

U-shaped pins are generally recommended for holding landscape fabric in place. We have found however, that the standard pins heave terribly when the ground warms each spring. (I trip over old landscape pins that have lifted out of the gravel every spring!)

In our most recent installation we switched to using spikes and washers. We find the 6" galvanized spikes don't heave when the weather warms.

Please make no mistake; these spikes aren't nails. Nails could be potentially dangerous! Spikes aren't as sharp as nails, and they won't rust, because they are galvanized.

U-shaped pins are sold in garden centres along with landscape fabric. Galvanized spikes and appropriately sized washers can be found in any big box hardware section.

Here is one last, but very important tip: landscape fabric tends to lift where two pieces of fabric overlap. 

It is really important to use u-shaped pins or spikes at least every 3" or 4"along any join. This may seem like a bit of overkill, but trust me, the last thing you want to see is an ugly flap of landscape fabric where it has lifted along a join.

So what am I going to do about my sorry looking gravel pathways?

I haven't decided, but I do know that I won't lay any new areas with landscape cloth!

Further Reading:

Read The Myth of Landscape Fabric by Linda Chalker-Scott, Ph.D., Extension Horticulturist and Associate Professor, Puyallup Research and Extension Center, Washington State University.

North Coast Gardening: Why I hate Landscape Fabric: An Unfair and Unbalanced Look at Weed Cloth and Professional Tips for Using Landscape Fabric Right by landscape designer Genevieve Schmidt

The Landscape Fabric Weed Barrier Myth by Todd Heft on Big Blog of Gardening.

Lots of people will tell you to put down newspapers are a weed barrier. Before you consider it, read this: Is Newspaper Toxic for my Garden? by Peter Kearney of Cityfood Growers.com.

Garden Prep: How to Make a Bed, with Cardboard by Margaret Roach of the blog A Way to Garden.

My Troubles with Landscape Fabric: Part 1

Private garden in Niagara-on-the-lake

Landscape fabric. It is not a particularly pretty topic to begin with after a bit of a blogging break, but bear with me. I think this is a series of posts worth reading if you plan to create a courtyard or pathway. (Coming up shortly, I promise to have more inspirational posts, new projects and a book give away.)

Not too long ago, I received a question from a reader by email:

Hi,

I am writing, first of all, to say that I love your blog, "Three Dogs in a Garden". As an avid flower gardener, I am inspired by the ideas I see there.

I've noticed that you have pea gravel paths in your garden. I am thinking of doing that, as well, but I wonder about your method for clearing them of leaves that collect in autumn. It seems to me that a leaf blower would also blow the gravel and a rake would rake up the gravel with the leaves and other debris. Do you clear the paths by hand?....

Thanks again for your blog, and happy gardening to you.

Jean 
Zone 4b, Wisconsin

I replied to Jean's email telling her that I use a standard fan rake. No big secret there! I do however, make an effort to clean up the leaves almost as soon as they fall. Freshly fallen leaves are so light and dry they seem to float on the surface of the gravel. Once the leaves get wet in the rain, raking up gravel along with the leaves is much more difficult to avoid.

As I typed out my reply, I felt I needed to warn Jean of an even bigger concern if she was thinking of adding gravel paths: working with landscape cloth. So I wrote back, touching on a few key problems and promising her I'd do a post on the subject.

Private garden in Niagara-on-the-lake

Fine Gravel Pathway at the Toronto Botanical Gardens

Pea gravel courtyard and path in a private garden.

Pea gravel pathways in a private garden

I always loved the look of gravel pathways and courtyards. They seem very old-world and even a bit romantic to me.

So when I planned out my garden, a little over ten years ago now, I included gravel pathways that would give the large circular garden at the very back of the property the European look I so admired.

This type of pathway also appealed to me as an affordable alternative to more expensive hardscaping with bricks or stone.

On top of the pleasing aesthetics, gravel paths seemed like a very doable project: you simply lay down some landscape fabric and cover it over with gravel. Sounds easy enough, doesn't it?

As best as I knew, landscape cloth was what professionals used for such an undertaking. Its use as a weed deterrent in flowerbeds was also very familiar. Here in Ontario, landscape cloth is commonly used as a low maintenance method of keeping weeds at bay in the public gardens that skirt new housing developments.

Only a few weeks ago, I watched a Chelsea gold metal winning British garden designer named Adam Frost install a landscape membrane (the English version of "cloth" or "fabric") to suppress weeds in his own personal garden.

Watch a clip from BBC's Gardeners' World showcasing Adam Frost's gravel garden.

Though this method seems like a great way to suppress weeds, I have found that it is actually fraught with problems. It appears to work initially, but the benefits are short-lived.

I even would go so far as to say I would never ever use landscape fabric in a flowerbed. 

And here's why:

• Even with regular raking, flowers and leaves are bound to fall onto the surface material (gravel, mulch, bark, etc.) and break down. That little bit of compost, added to the excellent drainage the landscape cloth provides, will actually work contrary to the originally intended purpose of suppressing weeds. 

Here you can see a good example of the debris that falls onto a pathway.

• Moving or dividing perennials will be more work than it would be in a conventional flowerbed. You'll have to rake away the surface covering (mulch, gravel etc.) and attempt to dig out the plant whose root ball will have grown well beyond the size of the original hole you cut into the landscape fabric. 

Planting the new division involves more raking away the surface material, cutting a new hole, planting and finally raking back the surface material. Trust me, you are going to be cursing that darn landscape cloth!

• The landscape cloth will make it impossible to add nutrition like compost or manure that your plants may require.

• Beneficial insects and earthworms, which aerate the soil, will find the landscape cloth blocks their natural movements and will avoid the area.

Jean emailed me back sharing her own experience using landscape cloth in a flowerbed:

"....Two years ago, I first killed weeds in an area along my side yard by laying down cardboard. Then I put down a double layer of landscape fabric over that and covered it with several inches of medium-sized bark chips. Last year, it looked fine. This year I have weeds poking through. I assume that the cardboard disintegrated and that squirrels or chipmunks dug into the wood chips and created holes in the fabric."

As Jean discovered the hard way, even the tiniest hole in your cloth is an open invitation for weeds. I have even found that weeds don't even need a hole. They will sometimes spread out there roots along the surface of the cloth and live quite happily.

Weeds in my garden growing on landscape cloth covered with cedar mulch.

The choice of cedar mulch turned out to be a HUGE mistake.

In an upcoming post, I will expand on my own experiences and express further concerns about any use of landscape cloth. 

Sadly, there aren't a lot of alternatives, so I'll touch on the various grade of cloth available, as well as share what I have found is the best way to work with this problematic material.