With the rain beginning, both the calendar and a step outside indicate that autumn is here and winter is not far behind. Pest management strategies need to change with the season, so here are some seasonal tips on pest control in the colder, wetter months.
Ants
If ants can’t find food outdoors they may try to come inside. Here are tips for excluding and managing them.
Asian citrus psyllid
The Asian citrus psyllid (ACP) has been found in scattered locations in Alameda County, and is already established in Southern California. ACP can spread the deadly huanglongbing disease (HLB), which has devastated citrus production in Florida. We love our citrus, so home gardeners, along with agriculture and scientists, need to work together to combat this threat. Here’s what home gardeners can do.
Citrus
Check your trees from time to time for damage and pests. Snails and slugs and root rots can be particular problems in wet weather. Here are some general tips on citrus pests.
Clean up
If there are any diseased leaves or old fruit under your trees, dispose of them. All that debris can host pests. Anything that looks diseased should not go in your home compost. Speaking of home compost, cover it with a tarp if the rain threatens to make it too soggy.
Fallen leaves
So long as these are not diseased, they make great mulch and excellent additions to the compost pile. Consider leaving some for habitat for overwintering pollinators and other beneficial insects.
Care for your Fruit Trees
If you’ve had peach leaf curl in your peaches or nectarines, fall and winter are the time to spray the trees to prevent or mitigate the problem next spring. Fire blight sprays for infestations in your apple or pear trees need to wait until the blossoms open, but winter is a good time to remove diseased wood. Fruit tree pruning for shape, structure and fruit production is best done in winter when the tree is dormant and you can see the structure better on fruit trees (except not apricots and cherries, which should only be pruned when there is no threat of rain).
Irrigation
With the shorter days and cooler temps, your plants already need less water. If the rains are plentiful, rain may alone meet your plants’ needs. Make seasonal adjustments as appropriate.
Root Rots
Check your surroundings to prevent rainwater from ponding around tree trunks (or near your foundation). Root rots are exacerbated by prolonged saturation of the soil or standing water near the base of trees and other susceptible plants.
Weeds
The rain will bring them out soon. Hand weeding and cultivation are easiest when weeds are small.
Snails and slugs
Moisture makes these pests more problematic. Tips for managing them.
The University of California Integrated Pest Management program provides great help for the pest problems each season. You can find the inspiration for the list above and much more autumn pest management info here.
Good pest management news! Starting January 1, 2025, in California neonicotinoid pesticides will no longer be available in retail nurseries or garden centers. These pesticides will only be available to agriculture and certified pesticide applicators. Neonicotinoids have been linked to the decline in honey bee and other pollinator populations. The European Union, Canada, Maine, New Jersey, and several other states have already banned or restricted these pesticides for non-agricultural uses. The California Department of Pesticide Regulation (CDPR) is reevaluating these pesticides in terms of their effects on pollinators, aquatic insects, and human health. Read more information here.