45April 20, 2016

When is bark mulch not bark mulch? The answer is, when it’s mulch.

There is a big difference between bark mulch and mulch. There are many places where you can purchase bags of mulch. There are only a few companies that are bagging bark mulch. The difference is that bags of bark mulch are primarily made up of the bark from softwood trees. The bark of these trees contains natural insect repellent properties. When you apply bark mulch on top of the soil, insects do not want to make a home in the bark mulch. Bark mulch will also insulate the soil preventing root damage from excessively hot soil. Bark mulch will also help to keep moisture in the soil better than bagged mulch. The secret is in the long fibers of the bark mulch. These fibers create pockets of space where air can act as insulation. This also prevents bark mulch from packing down.

Another advantage to bark mulch is that it keeps its natural color longer than bagged mulch. Most of the bagged mulch is a dyed material. The dye will fade quickly in the sun. Bark mulch will hold its natural color for most of the year. All things considered, bags of bark mulch are better for your gardens than bagged mulch.

The question that always comes up when buying bark mulch is how much bark mulch do you need to cover your gardens. If you apply 3 inches of bark mulch on top of the soil, you will effectively insulate the soil and you will have the maximum moisture holding capacity in your soil. In order to determine how much bark mulch you need, you need to know how long and how wide the flowerbeds are in your yard. If you multiply length by width you will get the number of square feet in your flowerbeds. This will be one of the determining factors in how much you will need to buy. Keep in mind that you do not need to add 3 inches of bark mulch each year. Once you have 3 inches of bark mulch in place, you will only need to add 1 inch the next year. There is no need to remove the old bark mulch from your beds. It will naturally decompose into the soil thereby increasing the organic matter in the soil. In the second and subsequent years you will be adding just enough bark mulch to maintain the 3 inches of protection for your plants.

There is a right way and a wrong way to mulch your plants. First off, any mulch material should not touch the stem or the bark of the plant. If the mulch is mounded up, say on the trunk of a tree, over time the mulch will cause the bark to rot from the mulch keeping the bark of the tree constantly wet. I know that these “ mulch volcanoes “ are a common practice, but they are the worst possible thing you can do to a tree. Please keep any mulch material away from the stem of your perennials, away from the trunk of your shrubs and definitely the mulch should not be touching the trunk of any tree.

The choice to use bagged bark mulch or bagged mulch is your decision. Just keep in mind that you should follow the guidelines I have given you on the amount of mulch to use and that you install the mulch properly.

Well, that’s all for this week. I’ll talk to you again next week.