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Getting Beautiful Landscapes·Off Drugs


The Organic Landscape Alliance ~ Growing The Business Of Beautiful, Healthy Lawns, Gardens And Parks ~Re-Thinking Pesticides

There are many advantages to reducing or eliminating the poisonous chemicals used in lawn and garden care. Medical researchers and environmentalists have cautioned parents, school boards and cities about health risks related to the use of pesticides.
Chemical poisons which kill garden insects (insecticides) and weeds (herbicides) are toxic to these unwanted species. But they can also be dangerous to things they are not meant to control: children, pets, birds, beneficial insects, and water. In fact, all stages of a pesticide’s lifecycle their production, transport, storage, use and disposal – have the potential to harm environmental and human health. As public awareness and questions about the safety of using garden chemicals has grown, so have ideas about doing things differently.
These days a new approach to plant care is starting to take shape. Organic or chemical-free landscapes are being promoted and offered by some members of the landscaping business.

Re-Thinking Landscaping

In 1998, a group of people who felt that lawn care and landscaping without the use of pesticides were important, got together to form the Organic Landscape Alliance (OLA). Since its formation, this
organization has had excellent growth in its membership. It has also won increasing public interest in organic gardening techniques, processes and products.
The Organic Landscape Alliance is committed to the development of organic horticulture or chemical-free plant growing. It gives professional landscape workers, arborists, park staff and turf managers (for those perfect green golf course lawns, for example) opportunities to learn about organic products and techniques. It also helps these professionals keep up with the most recent laws and regulations about chemical use.
The OLA also offers advice to homeowners and property managers who wish to learn about organic gardening and make it a part of their home or property maintenance.
Here and Now There and Later
There are two sets of very good reasons to think twice about putting poisonous chemicals on lawns and gardens where people spend a lot of time. The first set of reasons we’ll call Here and Now.
Here and now:

  • Chemical pesticides and fertilizers can contaminate surface water and groundwater
  • Poisonous chemicals are not good for the health of children who play on treated lawns
  • Pesticides can harm the health of family pets
  • Pesticides can be harmful to wildlife in gardens (birds, squirrels, etc.) as well as to good insects (bees, butterflies, ants and other important pollinators)
  • Poisonous chemicals can also harm beneficial soil organisms and damage the quality of the soil

The second set of reasons we’ll call There and Later.

There and later:

  • Garden chemicals fertilizers and pesticides are made from oil products, and manufactured with high-energy processes that burn fossil fuels. When the chemicals vaporize after application, they also give off greenhouse gases. So they contribute to climate change in their production, transportation, use and disposal!
  • In the long-term, toxic chemicals lessen the overall health of gardens and planted spaces: the species they are supposed to poison often become resistant over time, requiring bigger doses of chemicals to kill them. Many home gardeners use higher doses of chemicals on their gardens than farmers do on agricultural crops.


In the past few years school boards, city parks departments, cemeteries, golf courses, farmers, homeowners and community gardeners have all discovered the health benefits to people, water and nature of growing things chemical-free. Watch for “Chemical Free” signs in gardens and growing spaces as a sign of good health!

Gardening Chemicals and the Climate Change ConnectionMay 2004 -Toronto bans Pesticides!

After years of lobbying by concerned citizens, medical people, and environmental groups, the City of Toronto passed a by-law that bans the use of pesticides on private lawns and gardens as of 2005. Ontario doctors have linked pesticide use with diseases such as brain cancer and leukemia. The Toronto Environmental Alliance, one of the strongest supporters of the ban, stressed the need for education to help people care for outdoor spaces using natural, non-chemical methods.
Pesticide manufacturing and breakdown both contribute to climate change!

Some important facts about pesticides and climate change:

  • Pesticides are among the most energy-intensive products to manufacture
  • The manufacturing of common pesticide products such as Roundup or 2,4 D releases an enormous amount of carbon dioxide per pound of product manufactured
  • Canadian consumption of pesticides accounts for 0.3 million metric tonnes of carbon dioxide every year
  • Pesticides are derived from crude oil. The chemical breakdown of these products after their use on lawns and gardens

What’s good for organic gardens?

If you recognize the many benefits of going organic in your garden, you’ll want to do some reading and research on the best ways to care for plants without chemicals. The Organic Landscape Alliance has some good fact sheets on its website. Here are some broad tips for organic gardening:

  • Get educated and get started!
  • Fertilize naturally use compost and recycle grass clippings instead of chemical fertilizer
  • Well-aged manure and organic fertilizers are other good sources of nourishment
  • Aerate your soil for better air and water penetration and movement in the soil
  • Overseed with grass every year to fill in spaces where weeds might grow
  • Seed with new grass varieties to increase biodiversity and health
  • Mow grass “high” (not too short) to retain moisture, shade out weeds and strengthen roots
  • Water wisely don’t over-water remember: pumping water uses electricity that comes from burning fuel that contributes to climate change!
  • Safe garden-maintenance substitutes for poisonous chemicals include soaps, mineral oils, diatomaceous earth, biological control organisms (e.g. ladybugs to eat aphids), boric acid, ferrous phosphate, and pyrethrins.

Become informed about pesticides!


For more information on the relationship between the energy-intensive processes used in the manufacturing of pesticides, the breakdown after application, and climate change, see the Pesticide-free Ontario website http://www.pesticidefree.ca/kyoto.htm


  1. Define pesticide, insecticide, herbicide. Name one chemical product for each.
  2. a) List 3 reasons why people use pesticides, insecticides, herbicides. b) List some problems associated use of these chemicals in lawns, gardens etc.
  3. Explain some ways to care for plants without using chemical pesticides.Research: Repeat the Activity substituting fertilizers for ···cides.