Controlling Weeds

A weed is a plant that has mastered every survival skill except for learning how to grow in rows, once wrote humourist Doug Larson.  Weeds grow more quickly and vigorously than most of our valued vegetables, fruits, flowers and other landscaping plants.  While you may never be able to completely eradicate weeds, you can minimize their presence and enjoy a beautiful lawn and garden.

One of the best ways to gain some ground against these unwelcome intruders is with healthy soil.  Nutrient-rich soil will give your plants a fighting chance to become established and eventually crowd out the weeds.

There are several options available to improve your soil:

•    Alfalfa pellets contain nitrogen and calcium, which are especially good for flowers and lawns.
•    Compost is an excellent source of nutrients, beneficial soil organisms and fibrous material to help your soil maintain moisture.  A backyard compost bin allows you to reduce your landfill contributions while providing free soil amendments.  
•    Sea kelp provides trace minerals as well as a high ratio of potassium.
•    Fish emulsion (or fish meal) is rich in nitrogen.
•    Professionally produced, composted manure will be heated to the proper temperature to ensure it is safe.  The finished product provides generous amounts of phosphorus and potassium.  
•    Avoid metal in your garden; for example, aluminum stunts plant growth and damages plant DNA especially when the soil is acidic (i.e., a pH of 5.5 to 3.5).
•    Avoid chemical fertilizers which eventually add too much salt to the soil and kill plants—making this a counterproductive addition!

Alfalfa, sea kelp and other soil amendments typically include a NPK description, such as 2-5-10, which represents the ratio of nitrogen (N), phosphorus (P) and potassium (K).  Plants also require small amounts of magnesium, copper, iron, boron, sulphur and calcium.  When the soil composition is deficient or overabundant, plants can develop yellow leaves, stunted growth and reduced yields.  When this happens, weeds will outgrow valued plants.  

The most reliable way to determine which nutrients you should add to your soil is through testing.  Soil testing kits will reveal the pH and the levels of nitrogen, phosphorous and potassium.  By choosing soil amendments to correct the deficiencies, you can dramatically improve the health of your plants.  However, in some regions, very low or very high amounts of minerals and metals may be a problem, in which case, a professional laboratory test may be required to check for copper, boron, etc.

A relatively new, natural way to control weeds and fertilize is by applying corn gluten meal.  This product is sold as a powder or in pellets to apply to the top of the soil.  Researchers have discovered that the consistency of corn meal gluten prevents seeds from sprouting.  Apply this to the soil only after your plants are actively growing and water lightly to activate it.  Reapply every five to six weeks during the growing season.  Corn gluten also contains 10 percent nitrogen, which is useful as gardens are often lacking in this element.   

Another effective weapon against weeds is newspaper.  Pull out any large weeds then cover the area with several layers of newspaper and apply water.  The heavy, wet paper will block out sunshine preventing new growth while speeding up decomposition of weeds and their seeds.  Keep the newspaper wet for approximately five weeks then remove it and your soil will be ready for planting.  

Once your plants are a few inches tall, apply mulch around them to prevent weed seeds from taking root.  Mulch can be grass clippings, straw, wood chips, gravel, etc.  As well, many municipalities now collect yard waste from households, process it and sell the mulch back to their communities at a reasonable price.  

For weeds in walkways, apply boiling water.  This will kill them instantly.  Reapply as needed.

Hoeing is a fast and effective way to dig up weeds, which can then be added to a compost bin.  Be careful to keep any mature weed seeds out of the bin as some tough species can sprout and make your compost unusable.  

Vodka as a weed killer?  Some people claim this works wonders!  Mix together one ounce (30 ml) vodka, a few drops liquid dish soap, and two cups water in a spray bottle.  Spray it on the weed leaves when the plants are in strong, mid-day sun.  The alcohol reportedly breaks down the waxy cuticle covering on leaves, leaving them susceptible to dehydration in sunlight.

Lastly, to reduce weeding, be sure you are not unknowingly bringing home invasive plants!  Purple loosestrife, orange daylily, Mexican bamboo, English ivy and other plants can look quite attractive but grow like weeds!  These plants can hitchhike in potting soil and, occasionally, stores are not aware they are selling invasive species.  In their native habitats, these plants are controlled by the climate, insects, and other plants but when they are transported to new environments, these controls are no longer in place and as a result they can grow wild.  Save yourself many hours of weeding by quickly reviewing the Canadian Botanical Conservation Network’s list of common invasive plants.

Together, these measures will help you control weeds in your outdoor oasis!