The Best Type Of Mulch For Your Garden (And How To Choose)

With so many types of mulch on the market, it can feel impossible to know how to best use mulch in your garden. The best kind of mulch should nourish and protect your plants from weather and wildlife while helping you achieve the aesthetic you want for your garden. When deciding on the right mulch, it's a good idea to consider your plant's needs, your climate, and the desired outcome you want to achieve with the mulch. Do you want to keep weeds out? Add nutrients to the soil? Or just give your garden a clean, finished look? How often are you willing to reapply the mulch? Knowing the answers to the questions will help you narrow down your options.

To make choosing a mulch easier, mulch can essentially be divided into two categories: organic and inorganic. Organic mulch, as the name suggests, is made from natural, biodegradable materials like wood, compost, and straw. As it decomposes, it will affect the soil. Inorganic mulch, on the other hand, is made from durable, sometimes artificial materials that will not break down, such as rocks, gravel, recycled rubber, or plastic, which will cover the soil without adding any nutrients.

There are a wide variety of organic mulches to meet a range of garden needs. Wood mulch is one of the most commonly used types of organic mulch, with several options serving different purposes. Leaves and wood-based mulches are an excellent choice for suppressing weeds, keeping your garden tidy, and preventing your plants from competing for nutrients. Pine straw and cedar chips are excellent choices for acid-loving plants. Cedar and cypress chips also help repel certain insects. 

If adding nutrients to the soil is your main priority, choose compost or composted manure. Mulches like peat moss and coconut coir are best at retaining moisture. Cocoa bean hulls, a byproduct of chocolate production, offer a unique style with their rich, brown color and chocolate scent. Be aware, however, that cocoa bean hulls can be toxic to pets.

As organic mulches break down, they release nutrients into the soil. This boost of nutrients is especially beneficial in vegetable and flower gardens. However, because they break down, organic mulches will need to be reapplied about every 1 to 3 years, depending on the material and conditions. This extra maintenance is a drawback to consider, but they are generally less expensive than inorganic options. While organic mulches are beneficial if you live in a dry climate because they help the ground beneath your plants retain moisture, heavy layers of organic mulch may not be suitable for wet climates or plants that prefer dry conditions.

It makes sense to choose an inorganic mulch if you want something long-lasting and you're not concerned about adding nutrients to the soil. Although inorganic mulches are more expensive than organic mulches, materials like gravel, lava rocks, river rocks, and rubber suit a variety of styles. All of these mulches will suppress weeds like organic mulches. Rocks and gravel absorb heat, so they are a good choice for heat-tolerant perennials that survive hot summer days. If your plants do not need extra heat, but you still want the look of stone mulch, opt for light-colored rocks and stones, which help reflect light away from the ground, reducing the amount of heat that's absorbed. Adding a thin layer of gravel also helps improve the soil's drainage, which is beneficial for herbs like rosemary and thyme. 

Shredded rubber is another, more affordable inorganic mulch that suppresses weeds and retains heat, but due to flammability, it should be avoided in areas prone to wildfires. However, it has its downsides. It is still under question whether rubber can leach toxins into the soil. It may also give off an unpleasant odor in extremely high temperatures. Because inorganic mulches are so durable, you will need to replace them much less frequently than organic mulch, if at all.