Chop and Drop: A Mulch and Nutrient Builder

Chop-and-drop is a way to use the vegetation you already have in your garden to feed and enrich the soil. The descriptive name explains it well. Almost any vegetative growth can simply be chopped and dropped back to the ground to decompose, returning valuable nutrients to the soil, or to serve as mulch.

This gardening technique is often used by permaculture enthusiasts. Permaculture is a system that resembles nature and is based on natural cycles and ecosystems. In nature, leaves, small twigs, grasses, weeds, and other plants have a cycle. When they decompose, they add value to the ecosystem. Chop-and-drop emulates that process, and it is good for your garden.

Chop-and-drop composting

The technique is a type of composting method that is different from what many people think of as composting, where some sort of bin or pile receives a mix of natural materials to decompose, requiring moisture and regular turning.

The chop-and-drop method can be used any time during the year, but it is popular at the end of the gardening season when it is time to tidy up the garden or landscape and put it to bed for the winter.

Nutrient sources in your landscape

Plants, even weeds, have nutrients that, when returned to the earth, help enrich the soil. Consider grass clippings. Wise gardeners know that grass clippings are primarily made up of water and are a valuable source of nutrients. Leaving grass clippings on the lawn, particularly if they are not excessively tall, can result in the need for less fertilizer. 

It is the same with all those leaves that end up on the ground in the fall. Rather than bagging them up to be carted off to dispose of in a landfill, consider them nature’s gift! They are great sources for mulch to add around plants and shrubs, adding organic matter that is a natural way to improve the soil. For a light accumulation of leaves, it is possible to run over the leaves with the lawn mower and leave them on the lawn to sink between the grass blades and decompose, feeding the soil. For a heavy accumulation, rake them into a pile and run them over with a lawn mower to chop them up. They can then be used as mulch around flower beds, work them into the soil, or use for sheet mulching. Chopped up leaves decompose more quickly than those that are left whole.

Likewise, cutting other plants off at ground level, such as annuals, and leaving the roots at the end of the season in the soil to rot helps improve the soil. Expired annuals and pruned foliage from perennials or other plants can either be chopped into smaller pieces or left whole on the ground to decompose. Young weeds can be chopped and dropped but mature weeds that have gone to seed should be removed from the garden and discarded. Vegetative material can be cut with shears or by running a lawn mower over a pile if it does not hold twigs and branches. For tidy gardeners, chopping up the plant materials and then covering them with a layer of mulch may be desirable.

Plants to grow for chop-and-drop

While just about any plant can be chopped and dropped, some plants lend themselves well to the practice and are grown by permaculture practitioners to use as green mulch. You likely have heard of cover crops such as clover, vetch, or ryegrass, sometimes referred to as “green manure,” that help improve the soil and choke out weeds in late fall or early spring and then are turned over before planting warm-season vegetables. 

Other plants are noted for use as “green mulch,” when the leaves are chopped and dropped into the garden around other plants or seedlings. There are several plants used for this purpose. Among them are nasturtium, rhubarb, Swiss chard, and yarrow, but there are many others, such as weeds like purslane and dandelions. One of the most common chop-and-drop plants is comfrey, an herbaceous perennial that is easy to grow in average, well-drained soils in full sun to part shade. It has attractive foliage that when cut will grow back quickly. Cut the plants off at the base and chop into 3- to 4-inch pieces. Scatter the cut foliage around plants or seedlings or spread over the soil as a mulch layer. Comfrey’s soft leaves decompose quickly. 

Chop-and-drop benefits

This method taps nature’s plant materials to add back nutrients to the soil while reducing waste that may go to a landfill. It is composting without the work of carting garden waste to a compost pile. It also is a way for organic matter to decompose more quickly. 

Leaving the roots helps aerate the soil. Organic matter, when spread across the soil surface and left to decompose, enriches, and makes the soil healthier. Healthy soil attracts earthworms that are underground workers, loosening and improving the soil tilth. Healthy soils also reduce the need for fertilizers. 

What to avoid

Throughout the gardening season, any plants with disease problems should be discarded outside of the garden to reduce the chances of spreading disease. Do not add them to a compost pile. This is also important during fall clean-up. It is better to remove a plant entirely rather than risk any unwanted diseases that might affect other plants, even those in next season’s garden.