More growers are adopting no-till and cover crops to provide erosion control and help build soil organic matter. It helps suppress weeds and feeds soil biology.

Did you realize many specialty farms, urban farms and even gardeners apply mulch to gain residue and help achieve many of the same goals? It seems like a large row crop farm and small urban farm couldn’t be more different. However, when you look at growing practices, you’ll find more similarities than you expect!

Mulching is defined as any plant or suitable material applied to the land surface. Almost any material used to cover the ground could be considered a mulch. Mulching supports the soil health principle of keeping the soil covered.

Some of the advantages of mulching are weed suppression, soil moisture retention, increased soil organic matter, temperature regulation and erosion reduction. Mulch can be synthetic or natural, but natural is the most common, since these materials are often available on the farm. Plant residues, leaves, grass clippings and newspapers can be recycled and used as mulch. Straw and hay can also be purchased or otherwise sourced to use as mulch.

These materials can be left on the ground at the end of the growing season to provide cover over winter. They can also help increase soil organic matter as they break down, and serve as a source of carbon and nitrogen that impacts the soil’s nutrient availability. It is important to consider the carbon-to-nitrogen ratio of the mulch to prepare for any nutrient tie-up that may occur as it breaks down. Make sure the source is free from weed seeds or other contaminants to avoid making unwanted additions to your growing area.

Adding natural mulches

Typically, if transplanting plants, mulch is placed on the growing bed before transplanting. If plants are directly seeded, the mulch is added when the crop plant is well established. Some growers plant cover crops that winterkill, like oats and oilseed radish, and then space is made between the crop residue or raked aside to direct seed, or left in place for transplanting.

However, there are ways to incorporate mulches without long-term planning. For example, plant residues can be laid on walkways to reduce soil compaction, and tree leaves can be placed on top of beds, preferably after being composted. You can also put down newspaper on top of the soil before adding straw. This method helps increase weed suppression with multiple layers of mulch.

For everyone from a small backyard gardener to a large row crop farmer, mulch can provide great benefits. Each size and type of farm just needs to find the practices that lead to good-quality mulch on their scale.

For row crop farmers, cover crops, no-till and evenly spread residue from the combine are common ways to provide mulch. For smaller gardens and urban farms, these practices, along with adding natural mulch from materials already on hand, is a great way to keep the soil covered and improve soil health. Mulching works on all scales — it just looks different depending on the farm size.

Rodriguez-Soto is a regional urban soil health specialist for the Urban Soil Health Program with the Indiana Association of Soil and Water Conservation Districts. Kautz is a Natural Resources Conservation Service district soil conservationist. They write on behalf of the Indiana Conservation Partnership.