Basics of Mulch

Well, now that all the leaves from fall are gone and spring is not far off, it is time to start thinking about refreshing your planting and flower beds with new mulch.  New mulch in these beds has several key benefits that include:

  • Helps to maintain soil moisture. Evaporation is reduced, and the need for watering can be minimized.
  • Helps control weeds. A 2- to 4-inch layer of mulch will reduce the germination and growth of weeds.
  • Mulch serves as nature’s insulating blanket. Mulch keeps soils warmer in the winter and cooler in the summer.
  • Many types of mulch can improve soil aeration, structure (aggregation of soil particles), and drainage over time.
  • Some mulches can improve soil fertility.
  • A layer of mulch can inhibit certain plant diseases.

Here in Georgia, we have a couple staples when it comes to mulch – pine straw and shredded mulch (hardwood, cypress or pine bark).  Which one works best?  That is debate that there is not a real answer to.  It all comes down to personal preference.  Most times, it also comes down to cost.  Pine Straw mulch is going to be cheaper on the front end, but needs refreshing about every 6 months.  A shredded mulch, like either hardwood or cypress, costs more then double that of pine straw but outlasts pine straw by over 6 months.  Typically, we refresh a shredded mulch one time a year.

There is one other item to remember when you are putting out mulch.  Be cautious about using fresh wood chips for mulch.  While they are usually free from either your local municipality or tree removal company, they are still “green” and have not cured.  It is safe to use this type of mulch around woody plants like trees and holly style bushes, however, I would not use them near plants like annual flowers or fleshy plants like perennials and vegetable plants.  Because the mulch is green, it has not gone through the breakdown process like a mulch you would buy.  It will go through a decomposition cycle in which it generates a substantial amount of heat.  The heat from the decomposition can damage sensitive plants.  Not only that, but it ties up key nitrogen particles that are needed for plant development and health.