Landscaping with Mulch

Mulch can be separated into two groups, organic and inorganic.

Mulched paths reduce lawn work.

Organic mulches are derived from natural sources. They enrich the soil through decomposition.

• Compost is one of the best mulches for providing benefits to the soil, but that rich medium also provides a great place for weeds. Some compost is not very attractive. If appearance is important, use compost as a soil amendment and find a more visually pleasing material to cover it.



• Lawn Clippings are in steady supply during the mowing season, but let them dry before using. Spread them thin. Dry grass clippings will mat if spread too thickly. Never use grass clippings from a lawn that has been treated with herbicide. The best bet may be to add untreated clippings to your compost pile or use as mulch in the vegetable garden. Rich in nitrogen, grass makes a good vegetable mulch.



• Leaves are plentiful and free in many areas. They look and work better if partially ground and decomposed; otherwise they blow away or mat down when wet. Matted leaves form a barrier that prevents air and moisture from getting to the soil below.



• Sawdust is easily available in many areas. Use sawdust that is at least one year old if possible. Fresh sawdust can deplete nitrogen if mixed with the soil. However, sawdust on top of the soil should not present a nitrogen concern. Just keep an eye on the plants, and add a nitrogen-rich fertilizer if necessary.



• Wood Chips or Shavings are visually pleasing and provide all the characteristics of good mulch. Like sawdust, it is advisable to use older, decomposed material. Wood mulch that has not been properly aged or turned regularly can contain toxins and acids that are harmful to young plants. Fungal contamination can also occur with unseasoned wood mulch.



• Bark is sold as chunks, nuggets, or shredded. Bark is one of the most attractive (and more expensive) mulch materials, so it may be best used in more visible areas. Pine, cedar, and cypress are the most common varieties. In addition to its appearance, bark provides good weed prevention and moisture retention. Plus, bark nuggets will last for years.



• Straw is the leftover stem portion of harvested grain. It is lightweight and therefore not always easy to apply. It tends to blow around. It decomposes quickly and therefore needs replacing more often than other mulches. Its appearance may not make it a top choice for the landscape. However, straw does make a good cover for newly-seeded lawn areas.



• Hay, the stem portion of grasses, is often confused with straw. Hay is likely to contain weed seeds, so use it with caution. Both straw and hay are good plant nutrients and work well in the vegetable garden where weeds can easily be pulled.



• Pine Needles are sold in bales like straw which makes them relatively easy to transport and apply. They are long lasting and attractive.



• Topsoil that is sold at garden centers is basically packaged compost, a good soil amendment.



• Manure may also be best used as a soil amendment. If you use it as mulch, make sure it is dry and well rotted. Odor will not be an issue, but the appearance may leave something to be desired. Manure often contains seeds — a good reason to consign it to the compost pile.



• Newspaper or Shredded Paper is readily available, and paper decomposes quickly. Newspaper can be used in sheets or shredded. Paper is another mulch best used in the vegetable garden, unless you plan to cover it with another more attractive organic mulch. Colored ink is not good for plants, so don’t use the comics or magazines.
  

Inorganic Mulches are man-made. They work well and seldom need replacing, but they offer nothing back to the soil.

• Recycled Rubber is a great landscape alternative to bark or stone. Made from 100% recycled rubber product, It is safe long-lasting and natural-looking. Rubber mulch does the things you want mulch to do: helps retain moisture, moderates soil temperature, controls weeds and looks good in your landscape.

  Available in various natural shades to provide the look of wood bark, rubber mulch will not fade. It is heavier than bark mulch and less likely to blow away or float away during a heavy rain. Rubber mulch only needs to be applied to half the depth of traditional wood mulch. This product is excellent for playgrounds and is approved by the American Society for Testing and Materials (ASTM) when maintained at a 6" depth (compared to a minimum depth of 9" for wood mulches).
  

• Plastic warms the soil, plus blocks air and water. Plant growth is accelerated by the added heat and moisture retained underneath the mulch layer. Since plastic is solid, moisture must be provided by an irrigation system

  Black or clear plastic can be used.

  underneath or by careful hand watering. Usually sold in rolls, black or clear plastic can be used. Black is impervious to light, while clear plastic has been known to let weeds germinate and grow beneath. On the downside, plastic can overheat the plant’s roots or retain too much moisture, particularly if the plastic is covered with a layer of organic mulch for appearance sake. Plastic will freeze, so you may need to take it up in the fall. If used on slopes, any material placed on top of plastic will wash away or slide off. Plastic is well-suited for use in vegetable gardens.



• Brick or Stone offers a neat appearance but may not blend with every landscape design. They offer some weed control. Brick and stone (especially lighter shades) will reflect heat back up towards plants, which may be harmful. This mulch is certainly long lasting. Be careful — if pieces are strewn into the lawn, they can become potential hazards when mowing.



• Landscape Fabric (known as geotextile) is purchased in rolls and provides good weed control. Plus, unlike plastic, the fabric allows air and moisture to penetrate into the soil and plant roots. Overall, it's the best inorganic mulch for long-term use. Roots can become enmeshed in the fabric, making removal difficult, so be sure to remove weeds as soon as you see them.

This category includes products that are available in some geographical areas. Shredded cypress, cedar and eucalyptus are examples. Each of these offer good coverage, a nice appearance and pleasant fragrance.

Other regional mulches are byproducts of farming or manufacturing that are available in some areas. The most notable of these are pecan and peanut shells, cocoa and rice hulls, ground corncobs, salt marsh hay, and cottonseed. All work well and are often inexpensive. Check with your state or county extension service for local resources.

After you have decided which material to use, it’s time to put it down. Here are some things to remember:

• When the weather gets warm, we’re always in a hurry to get our landscape looking its best, so we pile on the mulch. But please - don’t put mulch down too early in the spring. Give the soil a chance to warm. Mulching too early will actually slow down the warming process. Normally, mid to late spring is the best time to put down mulch.



• The area needs to be weed-free before mulching.
  
  

  Pull mulch away from woody stems and tree trunks one to two inches.

• If you are mulching around plants, water them first, and then apply the mulch.



• One reason we apply mulch is to control and kill weeds. It can do the same to your desired plants, so be careful not to pile too much on them.



• To prevent stems and bark from rotting, pull mulch away from woody stems and tree trunks one to two inches. Also, if mulch is touching the plants, pests such as mice and slugs can get a great hiding place and a free lunch.



• In general, the bigger the pieces or chunks, the deeper the layer needs to be. Smaller-sized mulches will work their way into the soil more quickly.



• Seedlings can work their way through a thin layer of mulch, but too deep a layer could be impenetrable. Let your plants get off to a good start first. You can always add more after the plants are established.



• Mulch that is too deep will stimulate root growth in the mulch layer rather than in the ground. The resulting shallow root system is susceptible to cold and drought damage.



• For looks, consider the size and style of the area you are putting the mulch in. For example, pine bark nuggets may be too large for a bed of annuals, but perfect for an area around trees or shrubs.



• Pathways, slopes, and areas prone to flooding or high wind need special consideration. Consider using a heavier or larger material here.



• You may need to apply additional mulch in the summer to retain moisture and in the winter to insulate from cold.



• If your garden has a layer of winter mulch, pull it away gradually as the temperatures warm. If you remove it all at once, the tender new growth underneath could be affected by a late-season cold snap.



• If you wish, you can work most organic mulches into the soil at season’s end to improve the soil.

• A 1-2" layer of fine mulch should be sufficient, while a coarser material should be three - four inches deep. Too much of either type can suffocate your plants. In areas where you simply want to keep anything from growing, lay it on as thick as you like.



• Coverage will vary greatly based on what type of mulch you use and how deeply it is layered.



• Use our mulch calculator for a quick estimate.