About a week ago, my sister and I were having an email “conversation” about mulch. As I’ve said here many times, I don’t use mulch much because with my heavy, wet clay soil, all it often does is invite diseases and pests like slugs to come and infest the garden.
But there are a few places I do have to use it–specifically, places where mowers (mostly other folks riding mowers, not our walk behind battery operated one) throw seed laden grass and weed clippings into my beds and I use mulch there to suppress the weeds rather than being on my hands and knees constantly weeding–particularly now that my back is giving me more issues as I get older.
My sister’s question was about why her mulch was “disappearing” so quickly. She said it pretty much vanished in the course of a single year, instead of taking the normal 2-3 that it should have.
After I questioned her about her type of mulch (she is in Oklahoma and I know that cypress mulch is quite popular there) she said that she uses cedar, as do I. So that didn’t explain any differences.
One thing she has is landscape fabric under her mulch. I don’t use it for a few reasons. First, it’s not organic and doesn’t do anything for the soil.
Next, for the exact reason, she was emailing me about in the first place–weeds growing on top of the landscape fabric. Well, sure! Think about this logically. What do those who use it do? They put it down and then put down several inches of mulch on top of it. But what does mulch do? It breaks down, theoretically to enrich the soil.
Since it can’t get through the landscape fabric to enrich the soil, what happens it that it forms its own soil-like substance on top of the landscape fabric. Then, when weed seeds fall, they have a nice place to germinate.
The better practice, if there is a large area where weeds absolutely must be suppressed (and of course, chemicals are unneccessary for this job) is to lay down several sheets of newspaper (most newsprint is fine for this job because they are pretty much all printed with soy ink now. Just don’t use the color inserts–keep to the black & white pages). Then put down your mulch.
If you’re completely unconvinced that the newspaper is sufficient for your weed control, use cardboard boxes. This is the way I created my raised bed–I just laid the cardboard down over the grass in the area, filled the bed with soil and compost and away I went. I didn’t even do it in the fall–I did it about a month before I planted. And it worked fabulously and 2 1/2 years later there’s still not a weed in that bed.
As for the mystery of my sister’s disappearing mulch, I think it’s washing away. They’ve had several really severe late spring storms in the last few years. This past one actually damaged the roof of the place where she’s living and the hail broke windows. That’s surely enough to wash mulch away, particularly mulch that’s on top of landscape fabric, which can be a bit slippery.
I asked if her complex’s “mow & blow” contractor could have blown it away, but she said that it’s in an area where they don’t normally do maintenance. So I’m going with the spring storm theory. Anything that’s strong enough to break windows can wreak havoc on gardens and mulch.