Best Practices for Pest and Disease Management
Even if municipal codes do not prohibit the use of chemical pesticides or fertilizers, urban farmers should practice certain best practices to manage pests and diseases organically and limit environmental impact on soils and local water bodies, as well as risk to neighbors. These include:
- Maintaining plant health by ensuring soil fertility and proper growing conditions;
- Keeping gardens free of weeds, and especially Brassica weeds such as shepherd’s purse and yellow rocket, which can provide over-wintering for flea beetles;
- Choosing plants suited to soil, moisture, sunlight, climate, and other garden conditions;
- Choosing disease and pest resistant crops and cultivars;
- Practicing crop rotation and diversity;
- Practicing interplanting, or companion planting;
- Attracting or purchasing beneficial insects;
- Watering plants at the base to avoid wetting leaves and early in the day;
- Not touching healthy plants after being in contact with diseased or damaged plants; and
- Removing diseased plants and in some cases (i.e. late blight), disposing of these by burning or by bagging and bringing them to a landfill.
For information about these and other organic pest and disease management strategies, see:
- Resource Guide for Organic Insect and Disease Management by Brian Caldwell, Emily Brown Rosen, Eric Sideman, Anthony M. Shelton, and Christine D. Smart (2005), freely available online at http://web.pppmb.cals.cornell.edu/resourceguide/; and
- Growing Healthy Vegetable Crops: Working with Nature to Control Diseases and Pests Organically by Brian Caldwell, Chelsea Green Publishing, 2011, available for purchase at http://www.chelseagreen.com/growing-healthy-vegetable-crops.
The Cornell University Garden Ecology Project’s “Insect Research Update” offers pest management strategies specific to New York City area farmers and gardeners, available for download at http://blogs.cornell.edu/gep/ Research-Update-Handout.pdf. For diagnostic resources, information about common pests, and other publications about pests and pest management in the State, visit Cornell University’s New York State Integrated Pest Management Program website at http://nysipm.cornell.edu/.
Food scraps are the main attraction for animal pests. Deter animal pests by keeping all food scraps and waste tightly sealed, and using enclosed composed piles lined with hardware cloth. Also consider vermicomposting to keep food scraps out of open compost piles. Remove rodent habitats, such as piles of wood or lumber, and keep the perimeters of walls clear of shrubs and loose materials.
Lining the bottom of raised bed boxes with hardware cloth or chicken wire will protect crops from damage by moles and other burrowing pests. In other areas of the garden, laying hardware cloth under a thin layer of mulch can also help to prevent burrowing.
Line paths and borders with deer-repelling plants such as alliums, aromatic herbs, and daffodils, and purchase scent and taste repellents, being sure to alternate repellents frequently. Fencing can also help to keep deer out of gardens. A 7- to 8-foot wire or plastic fence or single strand of electrical fencing are both effective and inexpensive, though urban farmers must be sure to adhere to city codes that might regulate electric fencing, fence height, or construction material (see factsheet #26, Fencing).
Purchase commercial bird repellents such as visual scare devices, sonic repellers, and taste aversions. Constructing small cages of aviary wire and placing them over vulnerable produce will protect crops not only from birds, but also from deer, raccoons, rats, and other animal pests.
When planting cover crops, cover newly planted seeds with row cover until the plants emerge to protect against birds. Remove the row cover as soon as plants are a few inches tall to avoid stunting their growth or creating favorable conditions for disease.
Many of the organizations listed in the Appendix, such as the Brooklyn Botanical Garden, Just Food, and the Urban Roots Community Garden Center, provide resources and occasional workshops to teach urban farmers more about disease and pest management.
Check also with local Cornell Cooperative Extension offices, a listing of which is available from the Cornell Small Farms Program at http://smallfarms.cornell.edu/contact/local-contacts/.