Many of us use black shredded mulch, cedar mulch, and other materials to help protect our plants from weeds.
But is this shredded mulch actually a good idea for your organic gardening project?
Some wonder if their garden mulching might be killing perennials and preventing seeds from growing properly. Some people are also finding that they have sooty black patches on neighboring objects. Could mulch be the culprit, and what can you do to keep your plants safe?
Unfortunately, while wood mulches can be useful, shredded wood mulch like sawdust, bark, wood chips and root mulches can be a breeding ground for fungus. These fungi can shoot spores as far as thirty feet away, and are hard to get off of nearby light colored objects. They can also slow down the growth of established plants and new ones. That’s because wood, as a carbon, binds with nitrogen in the soil. Since plants need nitrogen to grow, this nitrogen immobilization can cause real problems. Wood mulches can actually steal the food right out of the soil.
The worst offenders for this are dyed mulches. They’re usually made out of chipped up old pallets that have been colored to be more appealing. It’s the worst kind to use around plants, and will often kill your new landscaping. Another problem is the acidic substance that forms when new, sap filled trees are turned to mulch. These can turn to a substance that will injure your plants. Chipped mulch that smells like vinegar should be avoided.
So, if shredded mulch isn’t the best idea for your garden, what should you use? Many people try straw, but if that straw contains seed heads, it’ll attract rodents and create weed problems. Plus, straw is also carbon rich, and can bind nitrogen the same way that wood mulch can. Shredded fall leaves, on the other hand, are an excellent option that releases nitrogen as it decays, instead of binding it.
There’s another great option for mulching, as well, and it might surprise you. Possibly the best mulching alternative is seasoned compost. After all, it can prevent weeds and retain soil moisture just as well as regular mulch or shredded leaves. Two inches of compost does as well as conventional shredded mulch. Plus, you get all the usual benefits of compost, like soil enrichment, and when the season is over, you can just till the compost in. Appearance wise, compost looks a lot like dyed black wood mulch, but without the same problems. Hot Tub Research
You can also try converting your fall leaves into good quality compost using just a shredder, or get some compost from your local garden center. Avoid wood and bark mulches, and steer clear of straw in favor of something that’ll help your plants grow better. Keep it six inches from the plant stems, just like regular mulch, and away from your foundations to prevent termites, and you’ll see better results in your garden. (For more complete info on garden mulching and ways to beautify your garden using a garden gnome, click here.)