Feb 062013
 

Soil fungi are essential for optimum plant health.  Mycorrhizal (Greek for “fungus roots”) fungi form a symbiotic relationship with plant roots in which the fungi absorb water and nutrients and bring them to the plant.  In return the plant provides exudates to feed the fungi.  Exudates are chemicals secreted into the soil by roots.  The chemical and biological interactions that occur between roots and their surrounding environment (i.e., the rhizosphere) are complex and not yet fully understood.  We do know however, that over 90% of all plants form Mycorrhizae, and that plants do not achieve optimum growth without this root and fungi relationship.

Mycorrhizae

Source: http://www.biomedcentral.com/1471-2105/6/178

There are three types of mycorrhizal fungi.  Ectomycorrhizal fungi grow close to the root surface and form webs around the roots.  These fungi are typically found among hardwoods and conifers.  The second type are endomycorrhizal fungi.  This type of fungi penetrates and grows  inside of the root.  Both of these fungi can dramatically increase the surface area of the root system, allowing the plant to absorb more water and nutrients.  The third type are ectendomycorrhizal fungi.  These are a hybrid of both ecto- and endomycorrhizae that are found in forests among the roots of alder, birch, and popular trees.  When applying mycorrhizae to your plants it’s important to use the correct type.  Most shrubs and perennials form mycorrhizae with endomycorrhizal fungi while conifers and hardwood trees benefit from ectomycorrhizal fungi.

How do I maximize the mycorrhizae in my garden soil?

Working Soil

Soil fungi are fragile and will be killed if the soil is rototilled, compacted, or treated with fungicides and pesticides.  So the simple answer is, don’t rototill your soil.  If your soil has been compacted by heavy machinery or winter snow, aerate it before planting.  Aeration improves air circulation and drainage which improves conditions for mycorrihizae.  Once aeration is complete, adding mycorrihizae will help speed up the recovery process.  Guard and Grow root tea includes both mycorrihizae and organic fertilizer.  Guard and Grow Root Tea will be especially effective when planting in soil that has been rototilled or otherwise damaged.

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.

Jan 112013
 

Shopping for organic produceFor years the agriculture industry, food and environmental scientists, and customers have debated the merits of organic farming and the benefits of eating organically grown food.  Even though Guard and Grow is committed to products that help produce organic food, it’s important continually examine the state of this growing industry as new scientific studies are released and as new products and techniques are applied in the field.

There’s not much debate about the benefits of fruit and vegetables in your diet, but how important is it to eat organically grown produce?  With the cost of organic food averaging 50 to 100 percent more than non-organic produce, are the benefits worth the cost?  Is eating organic foods more important for some people than others?  If you can’t afford a 100 percent organic diet, which foods are the most important if you want to limit your exposure to pesticides.

A Stanford University study recently analyzed 237 different studies that compared nutrient levels and pesticide levels in a wide variety of products and concluded that there was little significant difference in health benefits between organic and conventional foods.  However, none of the studies examined long term impact of convention foods on human health.  The longest duration among the studies was two years. The study also identified a wide range of farming techniques among the organic group that lead to differences in nutritional quality and contamination levels in different organic foods.  Overall researchers found that organic foods had a 30 percent lower risk of pesticide contamination than conventionally grown foods.

Another study lead by John Reganold from Washington State University from 2005 compared organic and conventional strawberry farms and determined that organic farms produced “higher quality fruit”.  The organic strawberries had a longer shelf lives and higher antioxidant activity than the conventional strawberries.

With these examples and many more studies from high quality sources producing contradictory findings, it’s clear that we still have a lot to learn about the impact of farming techniques on long term health.  As research gets us closer to the truth about the health and environmental benefits of organic farming, there are several “common sense” steps you can take to limit to protect your health by limiting your exposure to pesticides and other contaminants.

  1. If you can’t afford to buy all organic produce, choose organic fruits and vegetables that are most likely to contain pesticides.  The EWG’s Shopper’s Guide maintains a “dirty dozen” list of fruits and vegetables found to have the lowest levels of detectable pesticides.  The latest list includes apples, celery, bell peppers, peaches, strawberries, nectarines, grapes, spinach, lettuce, cucumbers, blueberries, and potatoes.  The EWG also provides the “The Clean Fifteen™ list of the produce least likely to test positive for pesticide residue.  This list includes domestic cantaloupe, grapefruit, kiwi, mango, pineapple and watermelon –  and these vegetables — asparagus, avocado, cabbage, eggplants, mushrooms, onions, frozen peas, sweet corn and sweet potatoes.
  2. Carefully wash your fruits and vegetables.  Use a produce brush for vegetables with thick skin and soak vegetables with rough exteriors like broccoli and cauliflower in water for a few minutes.
  3. Choose only undamaged fruits and vegetables.  Avoid fruits and vegetables that has been precut.
  4. Grow your own produce.  The best way to ensure you’re eating uncontaminated and healthy food is to grow it yourself.  In a properly managed organic garden you’ll have control over every stage of a plant’s growth.  You’ll also eliminate potential contaminants that can be present  as food is processed, transported and stored, plus you will enjoy fresh produce that’s likely to be more nutritious than store bought food.