Mulching Grass – The Benefits and How to Get Started

December 2018 - Sponsored by Kubota
By - Tim Nephew

To some people, mowing grass is an enjoyable time spent outdoors. To others, mowing can be one of the most time consuming but necessary weekly tasks they have to accomplish. If you have large areas to mow on your rural property, you may already be using your compact tractor with a mower attachment to manage those time consuming jobs. 

There are mower deck attachments for compact tractors up to 72 inches wide that give you the ability to cut acres of lawn efficiently and greatly reduce the overall time to get your mowing completed. One of the benefits of using a compact tractor mounted mower is the ability to cut taller grass that would clog a standard riding mower. The powerful diesel engine on the tractor coupled with the heavy duty blades of the mower can easily handle tough mowing jobs. 

If you tend to mow your grass at a taller height, one of the disadvantages can be the amount of grass clipping discharged by the mower. Large swaths of mowed grass can be unsightly and unhealthy for your lawn. To help eliminate the side discharge buildup, there are mulch kits that can be added to your existing mower deck that greatly reduce the amount of clippings left behind.

Mulching kits for tractor mowers are usually offered as an option from the manufacturer of your mower deck, but there are also generic kits available. The mulching kits work by adding an additional baffling underneath the mower. The output side discharge is also blocked, which traps the clippings under the deck. The clippings are then moved around under the deck to be cut multiple times and eventually blown back to the lawn surface.

Benefits of Mulching Lawn Clippings

Adding a mulch kit to your mower deck can help improve your lawns health. According to the University of Minnesota Extension Service, (https://extension.umn.edu/), mulching grass clipping has many benefits:

• Clippings are a valuable source of nutrients and you can use less nitrogen fertilizer if you recycle clippings to the lawn.
• Adding organic matter from clippings may help improve your soil if it is sandy, heavy clay or low in organic matter.
• Regular mowing will greatly reduce the need to collect clippings.

Grass clippings contain about four percent nitrogen which is the most important nutrient for grass. By leaving the clippings on your lawn and allowing them to naturally break down, you can provide up to twenty five percent of your lawns annual nitrogen needs. Also, when finely mulched, grass clippings help conserve soil moisture which can help your lawn avoid draught stress during periods of lack of rain.

Does Mulching Grass Increase Thatch

According to the University of Minnesota Extension Service, “Thatch is a layer of undecomposed organic matter that builds up between the soil surface and the actively growing green vegetation. A thatch layer will develop if organic matter is produced faster than it is decomposed.” Here are some causes of thatch buildup on lawns:

• Vigorous grass varieties
• Excessive nitrogen fertilization
• Infrequent mowing
• Low soil oxygen levels found in compacted or water logged soils

Thatch is one of those words that seems to be discussed a lot when talking about lawn health, but its definition is sometimes not clearly understood. Thatch occurs in lawns when turf produces organic material faster than it can be broken down. If you have too much thatch, your grass roots can experience damage causing the roots to dry out. In general, leaving grass or leaf clippings on your lawn will not cause thatch buildup as long as a mulching mower is used and the grass is mowed regularly.

When to Pick Up Grass Clippings

There are times when leaving grass clippings – even mulched clippings – is not in your lawns best interest. Even though compact tractor equipped mowers can go through a lot of tall grass, there are limits to how much can be mulched by the mulching kits. 

As a general guideline, you should pick up clippings instead of mulching if the lawn is infested with weeds or disease, or if the even the mulched clippings are too heavy which can mat together and smother the grass.

When mulching is not an option, there are grass baggers that can be added to your compact or sub compact mower. These large capacity baggers can be used for picking up excessive lawn clippings or leaf clean up in the fall. The baggers can also be used to occasionally pick up grass clippings if you want to use them for composting in gardens or flower beds.

Using Mulched Grass in Gardens and Compost Piles

Grass clippings by themselves can be used as mulch in a vegetable gardens, around flowers, shrubs and trees. Some of the benefits of using the clippings are weed reduction, moisture preservation and helping to moderate soil temperatures. 

When using only grass clippings as a mulch, it is important to put down thin layers of grass allowing each layer to thoroughly dry before adding another layer. Up to three layers of grass clippings can be added in between weeding. Applying thick layers of fresh grass clippings is not advised because it may have the tendency to smell, rot, or even mold before it breaks down.

Composting Grass Clippings

Composting describes the process of allowing microbes to convert yard waste such as leaves, grass clippings and plants to a mulch that can be applied to gardens or flower beds. Besides yard waste, other organic materials such as coffee grounds, eggshells, fruit and vegetable scraps, straw and livestock manure can be added to the pile. If compost piles are actively worked by watering and turning, they can be ready for use in five to six months. If materials are added and left to compost naturally, it may take a year or more for best results.

Using grass clippings are a great addition to any compost pile. The clippings are naturally high in nitrogen content which helps aids in the fertilization of the garden or flower bed. It is important to not use grass clippings in your compost pile if you have recently applied herbicide to your lawn. It is best to wait a minimum of three mowing’s before adding grass clippings as your garden mulch or in your compost pile after herbicide applications to prevent contamination to your garden or plants.