Jan 302013

Organic Mulches

Organic mulches are simply mulches made of organic matter.  Not only do organic mulches have many of the same benefits as synthetic mulches including protection from erosion, weed suppression and root protection, they also add nutrients and humus to the soil as they decompose, improving the soil quality and its moisture-holding capacity.Organic Mulch

Organic mulches provide benefits in both warm and cool seasons.  In summer months organic much protects soil from foot traffic, heat and dry conditions.   In cooler mid-spring months, organic mulches help to keep the soil from rapid warming and help maintain stable temperature and moisture levels.  Ideally, it is best to apply mulch after good rainfall or after soaking the ground to prevent dry conditions.

Organic mulch is generally inexpensive and simple to apply.  The following list identifies benefits and applications of some of the most common types of organic mulch.

Bark and wood chips are primarily used in landscape gardens to support the health of trees and shrubs.  Wood chips are considered by many gardening experts to be the best type of landscape mulch because they are inexpensive, easy to apply and very effective in protecting  roots, preventing weeds, moderating soil temperature and moisture, and as they decompose they improve soil quality.

Compost can be used as mulch and it is very effective fertilizer and a critical ingredient in maintaining healthy soil.  However, compost does not prevent weed growth like wood chips and inorganic mulches.  Compost is best used as a soil amendment rather than a mulch.

Grass clippings  can be used as a fruit and vegetable garden mulch to prevent weeds and improve soil quality.  Grass clippings should be applied in a thin 2-inch layer.  If you notice a bad odor after applying grass clippings, you have applied too much and there is too much heat in the compost layer.  Also be careful not to use grass clippings that have be exposed to herbicides and other toxins.

Hay or straw are both recommended for fruit and vegetable gardens and both provide good weed control.  Hay and straw decompose quickly and improve the soil as they decay.  Avoid using straw in extremely wet environments because rotting straw will attract slugs and other pests.

Leaves  are among the best garden mulches because they provide good weed control and improve garden soil as they decompose.  Leaves are inexpensive and available in practically every climate.  Apply leaves in a 2 inch layer and if they become soggy and matted, mix in hay or straw.  You can also shred leaves before applying them to prevent matting.

Newspaper  can be used as mulch if it is covered with another organic mulch like straw to keep it in place.  2 to 4 layers of black and white newspaper can provide good weed control.   Research has shown newspaper to be less effective than woodchips as mulch since it is more likely to attract termites and other pests.  Also, the moisture of the newspaper must be more carefully moderated to prevent anaerobic (too wet) conditions that prevent water and gas exchange or hydrophobic (too dry) conditions that cause water to “sheet off” of the mulch instead of penetrating into the soil.

Pine needles last longer than other types of mulch like leaves and straw and they are a good mulch for landscape shrubs and trees.  Pine needles are easy to apply and since they don’t compact, they easily allow water to filter into the soil.

Even though there are many important benefits to using both organic or synthetic mulches, there are also both correct and incorrect ways to apply and manage mulch.  In our next post we’ll review some practices to avoid and discuss some tips to achieve the best garden environment for your plants.

Jan 222013

What is mulch?

Mulch is a layer of material that you apply to the surface of your garden to improve the health of your plants.  Mulch can be organic material such as bark, leaves or wood chips, or inorganic material like rubber or plastic sheeting.  Mulch provides many benefits to both plants and their environment including:

  • Protection from extreme temperatures
  • Reduced presence of weeds and pests
  • Improved soil quality
  • Enhanced visual appeal of garden area
  • Helps maintain uniform moisture in the soil
  • Slows runoff and soil erosion
  • Helps prevent root injury
  • Creates a barrier between the ground to protect fruit and vegetables

 What types of mulches are best for vegetable gardens?

There are good applications for many different types of mulch depending on what vegetables you’re growing, the climate, and how early or late in the season it is.

Plastic Mulches

Generally, plastic mulches work well in the spring because they help warm the soil and promote early growth.

Black plastic mulch is the most common type of synthetic mulch and it is an effective means of controlling weeds and insulating the soil.  Since black plastic mulch will increase the soil temperature by about 8°F or more, it may cause soil to be too warm during summer months.  In this case, it must be covered with organic mulch or removed to prevent root damage.

Black plastic mulchWarm season vegetables including peppers, tomatoes,  melons, squash, and eggplant have been shown to grow better and produce more fruit when grown on black plastic mulch compared to plants grown on bare soil.  Plastic mulches also form a barrier to protect low lying fruits and vegetables like cucumbers and strawberries from contacting the soil, preventing  rot and keeping fruit cleaner.

Clear plastic mulch is the most effectivmulch in heating the soil and it is typically used in the early growing season.  Clear plastic does not prevent weed growth, however, so it should not be used in gardens that are highly susceptible to weeds.  Clear plastic will also need to be removed or covered thoroughly to prevent roots from overheating once temperatures rise.

IRT mulch is a dark colored mulch designed to provide the weed suppression black and the warming capability of clear plastic.  IRT mulch allows infrared radiation to pass through the plastic, but it blocks radiation that allows weeds to grow.  IRT mulch is still a relatively new product, and it is likely to increase in popularity as more research becomes available about its effectiveness.

Red plastic mulch also suppresses weeds and warms the soil, but large agricultural farms and gardeners typically use it primarily to boost the growth of certain types of plants.  A Clemson University study showed that red mulch can boost tomato yields up to 20%.  Red plastic mulch reflects low levels of blue light and a high percentage of far red to red light which has been shown to increase both the size of certain plants and their fruit.  Red plastic mulch will also likely increase in popularity as more research becomes available.

Guard and Grow UV Reflective Mulch

Guard & Grow UV Reflective Mulch

UV Reflective mulch is very effective in preventing infestation of pests including aphids, whiteflies, thrips and other insects.  Reflective mulch provides less insulation than clear or black plastic mulch so it can be left  on the soil later in the season without overheating the soil.  Guard and Grow is a leader in high quality reflective mulch.  Contact us today at info@guardandgrow.com with any questions about UV reflective mulch.