Installing mulch in your garden

By Melanie Mathieson
Gardening Guru

Now that you have made the decision to install mulch in your garden here are some simple steps to ensure that you apply it properly and do not get too carried away. Too much mulch can be detrimental to your plantings and can cause more harm than good.
The secret to successful application of your organic mulch product is to apply it to just the right depth. You do not want to apply it too thickly or you will prevent water and nutrients from penetrating the mulch layer. Sometimes when you apply mulch too thickly you can create a “bed” for weed seeds that land on the surface to germinate in. The purpose of applying mulch is to cut back on weeding not promote more weeds.
Before any type of mulch is applied, it is important that all-existing weeds and nuisance grasses are removed. Most of the weed seeds that you cover over with mulch should not have enough stored energy to germinate and grow-up through the mulch. If you have very thick weeds you may choose to apply a herbicide. There are a few herbicides (weed killers) that can be used in vegetable and perennial gardens to help control nuisance weeds and grasses, but they have several limitations, and should be used with extreme care. You must read and follow label instructions exactly as indicated, when using them. Also be absolutely certain that the label indicates that the product is safe to use around perennials and/or vegetables.
The soil should be moist but not soggy before starting to apply the mulch products. This is the time to install your weed barrier product, either landscape fabric or newspapers. If using landscape fabric use the instructions for installation from a previous column. As mentioned before, newspapers make an ideal organic weed barrier for perennial beds and vegetable gardens. A single layer of cardboard also works very well if you do not have newspaper. Layered newspaper shades out many growing weeds by shutting out the light, preventing the germination of weed seeds that were brought to the soil surface during cultivation for seedbed preparation. Newspapers are printed with soy-based inks and are safe for use but be careful not to use heavily coloured sections or glossy magazines as their inks may contain heavy metals or other soil contaminants. You simply place eight to ten full pages of newspaper around the circumference of the base of the desired plant. Make sure to keep the newspaper about an inch away from the trunk or stem of the plant. You can rip and fold the newspaper as desired to cover the entire soil surface. To keep the newspaper from blowing away you can water it and apply small mounds of mulch in strategic places before spreading it out evenly. Once the newspapers are in place apply a layer of any organic mulches of your choice. This could include any one of the suggested products from previous columns. You want to make this layer of mulch about 2-3 inches thick. Make sure it is of consistent thickness across the whole area. The newspaper barrier will usually last two growing seasons before it completely biodegrades. After a few years you need may need to add to your layer of organic mulch as it breaks down over time. You do not need to add another layer of newspaper unless the soil is showing through the mulch layer. Just reapply the newspapers over the existing mulch and then add more organic mulch product to regain the 2-3 inch thickness. One benefit to using newspapers as a weed barrier with organic mulch is the ease to which it can be moved aside to add more plantings as the season progresses. When adding more plants, select the location move the mulch product aside, cut thought the newspaper, dig a hole, plant the plant and then replace the newspaper, tearing as needed around the plant and then reinstall the mulch. No one will ever know that this is a new planting.
When applying mulch around young trees, extend the mulch from near the trunk out at least to the drip line (the ground area below the tree canopy). Established yard trees will benefit from a mulched area extending 2'-3' out from the trunk. In all cases, keep the area adjacent to the trunk free of mulch to help prevent damage to the tree trunk from excess moisture, insects and diseases, and voles and other pests. Excessive mulching can also stimulate undesirable shallow rooting. The same rules apply to mulching plants whether annual or perennial plants.
Now that you have your mulch product of choice installed you will soon have more time on your hands for other more desirable garden and yard tasks because your weeding chores will be cut down considerably.