Gardeners are forever facing the challenge of managing pest and disease pressures. While it is not realistic to completely avoid having weeds, diseases, insects or other pests in your garden, there are ways to prevent them from becoming unmanageable. Integrated Pest Management (IPM) is a holistic approach toward achieving this goal, and one important tool in the IPM toolbox is sanitation.
To prevent problems before they begin, sanitation can help avoid introducing new pests into your garden. This includes phytosanitation — making sure any plants you bring in from a nursery or a neighbor are clean.
Here are a few basic best practices to make sure you minimize risks from other inputs:
>> Check that any soil, potting media or compost you use in your garden is clean and free from noxious weed seeds and diseased plant tissues.
>> If you make your own compost, avoid putting seedy weeds in it unless you are confident the compost will be hot enough to kill the seeds.
>> Check that any equipment, garden pots and tools are free from soil that may harbor pests or pathogens. Clean and sanitize tools, especially any cutting implements, when moving between plants — to prevent accidentally infecting clean plants.
>> Wash your hands and gloves after handling infected or infested material.
Sanitation is very important when issues do arise to help control pests and diseases and prevent recurring problems. Treatment of the symptoms may not be feasible for economic reasons, or when labor is limited. And it might not be desirable, for example, in situations where there is a beneficial insect or predator that feeds on a pest. A spray might kill the beneficial insects in addition to the target, causing more harm than good.
Mitigating pests and diseases through sanitation might be as simple as pruning infected leaves or branches and removing them from your garden, either by burying them or bagging them and disposing in the trash. Fallen leaves and fruit can also be problematic; it’s important to remove and destroy infested or infected plants and debris, as they often serve as reservoirs harboring eggs or spores that can cause outbreaks or spread to neighboring areas.
Do not use leaf litter from infected plants for mulch, and avoid mowing over leaves in the case of fungal or bacterial diseases, as this is another way that spores and bacteria can spread. Managing fungal and bacterial diseases is especially challenging in our wet, tropical environment because splashing water from rain or irrigation can spread the pathogens. This makes it all the more important to promptly remove any infected material from your garden.
How do we know what material is infected or infested, and should be removed? Infected means any material that contains a bacterial, fungal or viral disease, while infested means material that harbors pests such as insects or their eggs, nematodes or other arthropods.
Contact your local UH Cooperative Extension office or master gardener program if you are not sure what is causing the symptoms you see in your garden. For more information, go to cms.ctahr.hawaii.edu/ce.
Emilie Kirk is a University of Hawaii at Manoa College of Tropical Agriculture and Human Resources (UH-CTAHR) assistant extension agent in sustainable and organic agriculture on Kauai.
