Working with Mulch: Tricks of the Trade

What’s so hard about mulch?  You shovel some around your plants and bushes, and that’s it, right? Not exactly.

There are a few tricks of the trade to getting the most out of your mulch delivery.  Apply too much, or in the wrong place, and you could choke out your plants.  Skimp on the mulch, and you don’t derive any benefits – because the point is to improve nutrition, weed control, and moisture retention.

To help get the best look and the best results for your landscaping, here are a few tips for how pros install mulch.

Mulching Tips

• Do not place mulch directly against plant crowns or tree bases. Mulch placed directly in contact with stems or tree trunks may retain excess moisture around the base of the plant.  Overly wet soil can foster a whole host of diseases, including crown rot. High piles of mulch can also become a bit of a varmint hotel, attracting predatory insects and bark and stem-eating rodents.  Give the base of your plants and shrubs a little bit of room to breathe.
• Mulch applied too thickly anywhere can cause problems.  In fact, it can cause a whole cascade of problems. A wood mulch when piled more than three inches high will start to rot much faster than usual.  It can create a thatch-like mat that keeps water from penetrating through to the soil below. Therefore, the plants you were hoping to protect are suddenly deprived of the moisture they need to live. Mulching too deeply can also cause the soil to remain continuously damp, but not nourished, contributing to root and stem rot problems in addition to depriving plants of needed oxygen. Apply a mulch layer no more than one to three inches thick.
• Thoroughly water newly installed wood or bark mulches.  Many good-quality mulches are stored in large piles that reach high temperatures.  When the mulch is spread or bagged, the high-temperature tolerant microorganisms that inhabit the mulch die as the mulch cools.  If the mulch is allowed to dry out or remain dry, nuisance fungi can colonize the mulch and create a water-repellent surface.
• Add a source of nitrogen to garden soils before applying wood–derived mulches.  Soil microorganisms that decompose organic materials such as wood-based mulches are effective competitors for limited soil nitrogen. So, if you fail to apply some nitrogen to the soil under your garden mulch, you could unwittingly be setting the stage to deprive your plants of needed nutrients. This may cause temporary nitrogen deficiencies, especially in annual and perennial plants. Yellowing of leaves often indicates a nitrogen deficiency. Lightly incorporate a source of nitrogen such as bloodmeal, urea, or a high nitrogen lawn fertilizer before applying mulch, and your landscaping will be good to go.

Make the work you do on your landscaping count.  Do the job right the first time; take the time to occasionally water and rake your mulch, and you will enjoy the effects all season.