Best Management Practices

Gardening &
Pest Control

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Safe Environmental Habits and Procedures for: Gardeners, Home Owners, and Landscapers

The Problem

Landscaping and garden maintenance activities can be major contributors to ocean pollution.
Soils, yard wastes, overwatering and garden chemicals become part of the urban runoff mix that winds its way through streets, gutters and storm drains before entering the ocean.

Poorly functioning sprinklers and overwatering, for example, waste water and increase the number of pollutants flowing into storm drains.

Fertilizers, pesticides and herbicides are washed off lawns and landscaped areas. These chemicals not only kill garden invaders, they also harm useful insects, poison fish and contaminate ground and ocean water.

Leaves, grass clippings and tree trimmings that are swept or blown into the street and gutter are also ocean polluters. These wastes clog catch basins, increasing the risk of flooding on your street, and carry garden chemicals into the ocean. As they decompose, they also absorb oxygen fish need to survive.


General Landscaping Tips

  • Protect stockpiles and materials from wind and rain by storing them under tarps or secured plastic sheeting.
  • Schedule grading and excavation projects for dry weather.
  • Prevent erosion by planting fast-growing annual and perennial grasses. These will shield and bind the soil.

Garden & Lawn Maintenance

  • Do not overwater. Conserve water by using irrigation practices such as drip irrigation, soaker hoses or micro-spray systems.
  • In communities with curbside yard waste recycling, place clippings and pruning waste in approved containers for pickup. Or, take clippings to a landfill that composts yard waste.
  • Do not blow or rake leaves into the street, gutter or storm drains.
  • Use organic or non-toxic fertilizers.
  • Do not over-fertilize and do not fertilize near ditches, streams or other water bodies.
  • Store pesticides, fertilizers and other chemicals in a covered area to prevent runoff.

Pesticide Alternatives

The "chemicals-only" approach to pest control is only a temporary fix. A more common-sense approach is needed for a long-term solution. It is called Integrated Pest Management.

Plan your IPMº strategy in this order:

1) Physical Controls

  • Caulking holes or hand picking
  • Barriers or Traps

2) Biological Controls

  • Predatory insects (e.g. Green lacewings eat aphids)
  • Bacterial insecticides (e.g. Bacillus thuringiensis kills caterpillars)

3) Chemical Controls – Your Last Resort

Use these least-toxic products:

  • Dehydrating dusts (e.g. silica gel)
  • Insecticidal soaps
  • Boric acid powder
  • Horticultural oils
  • Pyrethrin-based insecticides
Safe Substitutes for Pest Control
Garden Aphids and Mites – Mix 1 tablespoon of liquid soap and 1 cup of vegetable oil. Add 1 teaspoon of this mixture to a cup of water and spray. (Oil may harm vegetable plants in the cabbage family.)

Caterpillars – When caterpillars are eating, apply products containing Bacillus thuringiensis to leaves.

Ants – Place boric acid powder or hydramethylnon baits in problem areas, cracks and insect walkways. It is a mild poison, so be sure it is inaccessible to children and pets.

Roaches – Apply boric acid powder to cracks and entry points (see ants above). Place bay leaves on pantry shelves.

If You Must Use Pesticides
  • Use a pesticide that is specifically designed to control your pest. The insect should be listed on the label. Approximately 90% of the insects on your lawn and garden are not harmful.
  • Read labels! Use only as directed. In their zeal to control the problem, many gardeners use pesticides at over 20 times the rate that farmers do.

Pesticide Disposal

  • Household toxics–such as pesticides, cleansers and motor oil–can pollute the ocean and poison groundwater if disposed of in storm drains or gutters.
  • Rinse empty pesticide containers and use rinse water as you would the product.
    Dispose of empty rinsed containers in the trash.
  • City of Los Angeles residents should dispose of unused household toxics at a HazMobile instead of into the sink.
  • Call 1(800) 98 TOXIC (8-6942) for the location nearest you.
  • Dumping toxics into the street, gutter or storm drain is illegal!
  • Gardeners, landscapers and residents outside the City of Los Angeles can call the reference numbers listed in this pamphlet to learn where they can properly dispose of household toxics.
Other Phone Numbers to:
Spill Response Agencies Recycling & Hazardous Waste Disposal To Report Illegal Dumping To Report a Clogged Catch Basin
This is one in a series of pamphlets describing storm drain protection measures. Other pamphlets include:
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