The other day I was out in my yard doing some regular pruning and weeding. As many of you know, I live in a rental house at this time. I’ve not done a lot with landscaping here simply because I didn’t want to invest a lot of money on a home that is not my own. In my front yard, there is an area with large nugget bark over landscape fabric laid directly over the crappy clay soil. You all know my feeling about all of that—where’s my DISLIKE button?! But that is what the landlord provided, and it’s not really my position to change it. There is another area (first photo of this post) right in front of the raised deck front porch that had just 2 shrubs in it and a lot of empty area. I have made it my own. No landscape fabric. No nugget bark.
So I pruned the small Oreganum vulgare ‘Aureum’ (Golden Marjoram) to keep it tidy. (See the one very large yellow clump of marjoram on the right and the 2 already-pruned shrubs center and left.) I laid out the material I pruned off on newspaper and dried it in my garage. Now I have plenty of marjoram for cooking for at least the next 6 months. I love using culinary herbs in the landscape. And as I cleaned up the clippings, I noticed there were exactly 5 small weeds growing in the area which is about 4′ x 12′ in size. I had not weeded it since fall when I laid dried leaves (to compost in place) as mulch.
One of the reasons why there are so few weeds in this garden is that most all of the earth was covered completely with both leaf mold mulch and foliage. Each one of those things really helps prevent so many weeds, but both together do an excellent job—as evidenced by getting only 5 weeds in on toward 6 months.
That garden area was easy to maintain. Then I moved on to the larger nugget bark area. I wish I’d snapped a photo BEFORE I weeded. I’ve lived in this house 3 years. When I moved in, the nugget bark completely covered the landscape fabric, and there were no weeds. I have had to weed that ‘weed-barrier-protected’ garden bed numerous times since moving here. Though this photo at right is not my yard, it’s typical of what is seen all the time around here, and was very much what my little front garden area looked like. Grass and weeds happily growing on top of bark mulch over top of landscape fabric weed barrier.
The reason landscape fabric (and black plastic) is not a good weed barrier in many locations is because not all weeds get into a garden via roots under ground. Here in the Willamette Valley (OR and WA) is raised a lot of nursery stock and a lot of turf grass. And because of all the other cultivation around here and our wind factor, 50% of weed seeds arrive in our landscapes from the sky. For this reason, weed barrier cloth simply doesn’t work here. We have some very aggressive weeds here that can grow in an incredibly small amount of dust. Since bark is organic, it WILL decompose over time. That decomposed matter makes lovely substrate for opportunistic weed seeds to germinate in.
But I digress.
In my weed barrier garden, the nugget bark had decomposed leaving fabric showing (see photo at right). I found this small lobelia volunteer and left it growing. I did not plant it there, and it is growing right through the fabric as were many, many weeds and grasses. Granted this garden bed is larger—maybe 3 times larger— than my other small bed, but it took much longer and more physical exertion to clean up, and I didn’t prune anything. It was all weeding. To make the weeds a little easier to pull, I sprayed them with vinegar to kill the top growth several days previous to this weeding foray.
My client’s all ask me for low-maintenance landscapes. And I always discourage weed barrier fabric, and encourage a thick layer of leaf mold compost instead. By using compost as mulch, I am slowly improving the crappy soil on this lot. Use of weed barrier will never improve the soil because the barrier prevents the mulch from merging into the crappy soil and as it composts. If you want plants in a weed-barrier garden to enjoy better fertility, you will have to apply supplemental fertilizer—which is expensive and increases your carbon footprint (and possibly contributes to pollution of the watershed if not applied properly). I’m all about creating good soil that will feed the plants, and use of weed barrier prohibits that. Plus, I had MUCH more weeding—work—in the weed barrier bed than in the leaf mold mulched bed.
So which garden bed is more sustainable, and most easily maintained—hence most successful? My money is on the no weed barrier, leaf mold covered bed. That afternoon’s labor was as much science project as I needed to prove that use of weed barrier does NOT reduce work in the garden—at least not where I live in the Pacific Northwest.