Garden Mulches

We’re getting into the summer season and the days are getting hotter and the weeds are growing faster. One of the tricks in the gardener’s toolkit is mulches. Mulches have many benefits, including suppressing weeds, conserving soil moisture, moderating soil temperature and minimizing the splashing of soil onto lower leaves during rain or watering (which can introduce diseases such as wilt and blight that harbor in the soil). Organic mulches will also decompose over the season and eventually enrich the soil. Mulches do have some negatives, such as providing a place for pests such as slugs to hide during hot summer days, but I think the advantages outweigh the negatives.

Now is the time to consider mulching, before plants get bigger, the weeds get out of hand, and the soil dries out. It is often useful to see what other gardeners are doing, so I took a stroll around the garden today to do a survey of mulching techniques. Our gardeners are using an interesting variety of techniques, the simplest and cheapest being the dust mulch. What do you like to use for mulch?

Dust mulch

Dust mulch is created when the top surface of the soil is disturbed, allowing it to dry out. Dust mulching is moderately effective at retaining moisture and the dry soil environment minimizes the germination of weed seeds. It is, however, fairly labor intensive to create and maintain. The best tool to use to create the mulch is the scuffle hoe. While there are many variations of this hoe, it is essentially a blade that lies parallel to the soil and slices through the top layer, severing weeds at their base and disturbing a thin layer of soil. There is also a hand version of the tool for close work in small beds.

Composted leaf mulch

There are many organic, plant-based types of mulch used for gardening. Factors to consider include cost, effect on soil, weed seed content, and permanence. Organic mulches seen in the garden or commonly used in New England include chopped straw, composted leaf mulch, salt marsh hay, grass clippings, buckwheat hulls, cocoa bean shells, pine needles, wood chips, sawdust and shredded newspaper.

Paper mulch combined with chopped straw

The third type of mulch is the sheet mulch. This category includes black plastic mulch, which I used in the past for tomatoes and peppers. Since we’re not supposed to use it in the Community Garden, I have found a paper substitute that works pretty well and decomposes by the end of the season so it doesn’t have to be pulled up. Other gardeners are making extensive use of landscape fabric. In choosing one you should be sure it is porous enough to allow the rain to penetrate and be absorbed or you will be making a lot of trips to the well.

Landscape fabric combined with wood chips