Home gardeners often express interest in environmentally friendly gardening and landscaping. As an alternative to pesticides we recommend using native plants more often; keeping trees, shrubs and turf healthy to reduce the need for pesticides, using mulch appropriately, planting the right plant in the right place and planting for birds, bees and butterflies to improve landscapes.

Gardeners can prevent pests by sanitation (cleaning tools and disposing of disease or insect infested plant material), screening new plants looking for pests before purchase, hand-picking insect pests when possible, using a fly swatter, rinsing plants with a strong stream of water and trapping using sticky traps.  When we do recommend pesticides, we try to encourage gardeners to use organic pesticides.

So what is an organic pesticide? Generally an organic pesticide is a pest management chemical that is designed to breakdown quickly and often times are derived from an organic source such as plant extracts. We do not recommend homemade pesticides; most home remedies not properly tested and since we home gardeners are not chemists, mixing chemicals can be unsafe.

Pesticides generally are found in three categories; insecticides to control insects, fungicides to control fungal infections and herbicides to control weeds. Sometimes these organic pesticides are not quite as effective as their synthetic counterparts but are useful to gardeners to control pests. Luckily for environmentally conscientious gardeners there are many organic pesticide options available.

Organic options for garden pest control:

Organic and Biorational Herbicides

• AXXE or Ortho Ground Clear with ammonium nonanoate
• Home Plate with caprylic and capronic acids; palm oil
• Scythe with pelargonic acid; Pelargonic acid, also known as nonanoic acid, occurs naturally in many animals and plants, including geranium (Pelargonium spp.).
• Brand name herbicides with vinegar

Organic Insecticides

• BT (dipel or thuracide) derived from the bacterium Bacillus thuringiensis 
• Avermectin occurs naturally as a product of fermenting Streptomyces avermitilis
• Emamectin  Synthetic version of Avermectin.
• Spinosad – derived from the bacterium Saccharopolyspora spinosa
• Neem Oil – derived from the seeds of a chinaberry tree; smothers a wide variety of pests
• Clove oil/cottonseed oil mix – kills insects by smothering them
• Azadiractin – derived from the fruit of the chinaberry tree; kills a wide variety of insects; made by many manufacturers
• Kaolin clay – mixed with water and prayed on plants creates a barrier to insect feeding
• Safer soap – potassium salts of fatty acids; mixed with water and sprayed on plants; creates a barrier to insect feeding
• Pyrethrum – derived from the flowers of chrysanthemums; kills insects on contact
• Pyrthroids – synthetic versions of pyrethrum; a class of powerful insecticides
• Rotenone – made from tropical plant roots; is a general insecticide
• Horticultural oils – smothers insects and disease spores when applied in the winter on dormant plants
• Sulfur – sulfur has been use in insect and disease control for millennia
• Diatomaceous earth – a fine powder that sticks to insects and irritates their bodies

Organic Fungicides

• Bordeaux Mix with sulfur and lime – used for millennia for insect and disease control
• Blue Copper – general fungicide

***Note on Pesticide Labeling

The US EPA regulates pesticides and passes the responsibility for safe pesticide use down to the end user. The labeling on the pesticide package is information that EPA forces the manufacturer to include in the packaging and that the end user is required by law to read. Read the label of any pesticide that you intend to use. Follow the labeled instructions for safe and proper use closely. Wear any and all personal protective equipment such as gloves and goggles that the label requires.