Environmental/cultural changes
Pests can be controlled by changing your growing environment. For instance, environments that are extremely moist is an ideal home for fungus gnats, while very hot and dry areas are favored by mites.

I.D the pest that is a problem in your garden, learn about their ideal growing conditions and try to make it less hospitable. Remember to consider how these changes will affect your plants. Cultural changes might not be a good solution in some cases.

Spraying plants
Spray plants with a fairly strong blast of water may be a way to rid your gardens of some pests like mites and aphids. The water will usually dislodge these pests easily, however, it's not a perfect method either. Water pressure could kill your plants (snap stems, remove leaves or snap the plant itself). When using this method, always spray around the perimeter of the garden area as the pests will probably survive the treatment, leaving them hanging around the garden.  

Handpicked
Pests like mites and aphids are not treatable using the handpicked method. However, larger pests such as scale insects and mealybugs can be removed simply by picking them off. This might not be the method of choice for those that are afraid of bugs. If you're afraid of touching them, consider using a pair of tweezers or similar item. A small handheld vacuum can be helpful in removing whiteflies.

Trapping
Flying insects can be controlled using yellow sticky traps. Pests on or around the plant won't be captured by these traps. In general, only flying insects will be controlled this way. Sticky traps can be purchased at your local garden center.

You can make your own from yellow cardboard or thick paper by covering the surface with petroleum jelly or another sticky substance. Whiteflies, winged aphids and fungus gnat can be controlled using this method.

Trash it!
Plants that are excessively infested should be thrown out. In some instances, it's not worth the effort and time trying to control the infestation. Other plants might be sacrificed if the excessively infested plants remain in the garden.

Biological controls (Predatory Insects)
Not all bugs are bad. Some bugs and insects that are beneficial to your garden by keeping the bad pest population under control. Once the bad or unwanted pests are gone the beneficial insects will die out shortly after or find a new location in search of food.

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