Natural Pest Control

There was a time when any sign of chewed or spotty leaf was met with a blast of pesticide or a cloud of powdered fungicide. In these more environmentally aware times, the approach of choice is Integrated Pest Management (IPM).

IPM looks to provide the best growing environment for a plant and then apply the least damaging cure for problems. While this was initially developed for agricultural use, it can be adapted to the home garden. Below is a list of simple steps to consider in planning your garden. After that, there is a protocol for steps to take to solve a problem.

1) Biological controls (beneficial insects). There are good bugs and bad bugs. The useful ones are called beneficial insects, or beneficials. The beneficials include cheerful ladybugs, which eat aphids and are often available live in garden stores. Lacewings are lovely insects that eat aphids, insect eggs, mealy bugs, and scale. Spiders eat aphids, flies, leafhoppers, and mosquitoes—so leave that web in peace! While they don’t eat insects, honeybees pollinate plants and are essential if you grow vegetables. Because there are so many good insects, it is important not to spray pesticide willy-nilly, taking out the good with the bad.

2) Crop rotation. While this sounds like something best left to farmers, some garden favorites, like tomatoes, should not be grown in the same soil year after year. It is best to switch out your vegetables and grow them in different containers, or at least in different soil.

3) Choose your varieties carefully. Plants and seeds are usually marked “disease resistant” if they are a particularly hardy variety. You can’t always do this, but if you have a choice, pick the plant that is disease resistant.

4) When you have a diseased plant, remove and destroy any infected part of the plant (or all of it) so that the infection will not be transmitted to another plant.

5) Choose plants that will thrive in their site. Plants flourish in particular environments. Trying to grow plants in the wrong place (shade loving plants in the sun, for instance, or dry climate plants in the middle of a rain forest) will weaken them and make them more vulnerable to disease or predation.

6) Pay attention. Watch your garden and take note of what seems to work…and do more of that!

If, despite your best planning efforts, you have a problem in your garden, then IPM suggest you take these steps in this order to solve it:

a) Cultural action – remove a plant or part of a plant. Put a different one in that spot.

b) Mechanical action – remove pests by hand.

c) Biological action – release beneficial insects.

d) Chemical action – As a last resort, use the least environmentally damaging herbicide, insecticide, or fungicide.

This may sound complicated, but it comes down to common sense. Choose the right plant, put it in the right spot, and give it what it needs to thrive.

Most Common Garden Pests

Below is a list of 20 most common garden pests:

Organic garden pest control and common garden pests

Outdoor Pest Control:

Pests ControlledActive
ingredient
Mode of ActionFormulationFeatures/Uses
OUTDOOR INSECTSpermethrincontactliquid spraySynthetic pyrethroid for tree and garden
OUTDOOR ANTScarbarylcontactgranulesLawn/garden ant control
MOSQUITO LARVAEBacillus
thuringensis
israelensis
stomach poisonpelletsBiological insecticide for standing water
outdoors
CATERPILLARS,
WORMS
Bacillus
thuringensis
stomach poisonliquid sprayBiological insecticide Bacteria disrupts stomach lining
DEW WORMScarbolic acidcontactsoap barApply to lawn
INDOOR/OUTDOOR
NON-FLYING INSECTS
permethrincontactaerosolSynthetic pyrethroid for cracks and crevices
CRAWLING INSECTSsilicon dioxidelong lasting
residual
abrasive
powder
Diatomaceous earth
scratches insects body
SCALE, MEALYBUGS,
INSECT EGGS
mineral oilcontact, residualliquid sprayDormant oil breaks down insect’s waxy coating
APHID, SPIDER MITE,
WHITEFLY,
CATERPILLAR, SCALE,
THRIPS, ETC.
vegetable oil;
pyrethrin
contactliquid sprayMiticide/insecticide; outdoor
WASPS, HORNEresmethrin;
permethrin
contact, residualfoam, jet spraySpray wasp or hornet nest
FUNGUS GNAT, THRIPSHypoaspis mitespredatorgranulesAvail. for indoor or outdoor
SOFT-BODIED INSECTSpotassium salts of fatty
acids
contactliquid sprayMild insecticide
Dessicates body fluids
OUTDOOR INSECTSrotenonestomach poisonpowderNatural organic insecticide; extremely toxic to
fish
OUTDOOR INSECTScarbarylcontactliquidSpray fruit, vegetables, lawns
APHIDS, SPIDER MITE
WHITEFLY, CATERPILLAR, PSYLLID, ETC.
insecticidal soap;
pyrethrin
contactliquid sprayAvail. in outdoor yard/garden or indoor house plant forms

Indoor Pest Control:

PestColor/ DescriptionPlant DamagePlant HostsFeeding ActionCultural Control
APHIDusually green
or black
wilting flowers/
yellowing
most plantssuck sapremove heavily
infested leaves
FUNGUS
GNAT
small black
flies
root damagemost potted
plants
larvae
eat roots
allow soil to dry out
between waterings
MEALY BUGcottony, winglessplant stuntingmostly cacti and
succulents
suck saphand-picking
SCALEdark brown;
shell-like,
wingless
leaf spottingmost plantssuck sappruning or picking
SPIDER
MITE
minute red or
two-spotted mite
leaf spottingmost plantssuck sapmisting reduces
population
THRIPStiny, dark
slender flies
silvery streaksmost plantssuck sapkeep dry
WHITEFLYsmall white
moth-like insects
plant stuntingfuschia, daisies,
tomatoes, etc.
suck sapsticky yellow boards
indoor pest control methods

Fungus Pest Control:

Pests ControlledActive IngredientMode of Action FormulationFeatures/Uses
FUNGAL ROT, SOIL BORNE
INSECTS
captan; carbarylprotectant
contact
powderFungicide/insecticide
applied to bulbs and soil
MILDEW, BLIGHT, BLACK
SPOT, ANTHRACNOSE
copperprotectant
contact
wettable
powder
Prevents fungal disease
on yard/garden plants
POWDERY MILDEW, BLACK
SPOT
folpetprotectant
sytemic
wettable
powder
Prevents fungal disease
on roses and ornamentals
POWDERY MILDEW, RUST,
BLACK SPOT
triforineprotectant
sytemic
liquid sprayPrevents fungal disease
on roses and ornamentals
POWDERY MILDEW, BLACK
SPOT, ANTHRACNOSE, RUST
sulphurprotectant
contact
wettable
Powder
liquid spray
Prevents many fungal fruit and foliage
dise
POWDERY MILDEW, BLACK
SPOT, ANTHRACNOSE, ETC
INSECT EGGS, SCALE
Sulphide sulphurprotectant
contact
liquid sprayPrevents fungal diseases on fruit/foli
age; used with
Dormant Oil to kill
overwintering insects; fungal spores
FUNGAL DISEASES; INSECT
PESTS
copper; carbaryprotectant
contact
powderInsecticide/fungicide
fungus pest control methods

Weed Pest Control:

Pests ControlledActive IngredientMode of ActionFormulationFeatures/Uses
KILLS ALL VEGETATIONamitrole; simazinesoil residualliquidNon-selective herbicide
One year soil residual
CKICKWEED, CLOVER,
THISTLE
M.C.P.P
(mecaprop)
contact
systemic
liquidSelective herbicide for broad-leaf weeds
BROAD-LEAF WEEDS2,4-D; dicamba
mecoprop
contact
systemic
liquidSelective herbicide for broad-leaf weeds in lawn
MOSSferrous sulphateLiquid and
granular
Controls moss in lawns; do not use on cement
KILLS ALL GREEN VEGETATION INCL. GRASS AND
THISTLES
glyphosatsystemicliquidNon-selective herbicide for
perennial weed control
DANDELIONS, PLANTAIN2,4-Dcontact
systemic
solid barNon-volatile, no spray drift kills broad-lf. weeds in
lawns
weed pest control methods