One of the realities of living in a region with lots of sunshine, rainfall and humidity throughout the growing season is, equal to the diversity of crops that can be grown, is a wide variety of pest pressures that can be encountered. At the end of the season, insect and disease populations can be extremely high. Each pest organism will have unique characteristics related to how it is transmitted from one year to the next. As growers are taking stock of the successes and challenges of the season, this is also a ripe time for focusing on farming practices that deter insect and disease issues.
Remove Crop Debris
Months of heat and humidity result in healthy populations of insects, both beneficials and troublesome plant pests. Common insect pests like squash beetles, harlequin bugs, and cucumber beetles will be encountered every growing season. Field cleanup at the end of season is a simple but effective way to minimize overwintering populations. Being extremely thorough in removing crop debris from the field requires labor and time, but these efforts will pay off with reduced pest pressure the following year. If crop debris is collected in a compost pile on the farm, it’s important to ensure that adequate moisture and temperature levels are met to fully decompose this plant material. If not, this collection of crop leaves and stems can create a nice overwintering habitat for insect pests.
Cover Crops
Cover crops are essential for soil conservation, nutrient management, and habitat for beneficial organisms, yet some species may create overwintering habitat for pests. Cover crops in the Brassica plant family - including radishes, mustards, and rapeseed - benefit the whole farm ecosystem. They effectively suppress certain plant diseases and nematodes. Unfortunately, they can also attract insect pests like harlequin bugs. If you’ve had a particularly problematic insect issue, do your homework on how those pests overwinter, what crops they prefer, and be prepared to either switch cover crops, or be ready to take action to control those pests before your cash crops are planted.
Field Sanitation Minimizes Disease
Disease pathogens can also carry over from one season to the next. While some diseases are spread early in the spring by wind and rain, common diseases like early blight (Alternariaspecies) and powdery mildew (several species are problematic) can overwinter on plant debris left in the field.
Early blight is a problem on potatoes, tomatoes and peppers. While growers see signs of this disease every year, managing plant debris at the end of the season is critical to ensure little carryover from this season to the next. If disease pressure has been very high, it may be best to burn the affected plant material rather than composting, to ensure the pathogen won’t survive.
The same is true for plants affected by powdery mildew, which can impact many different crops, and can overwinter on crop debris or on wild plants adjacent to production areas. It’s important to survey field borders, windbreaks, and hedgerows for weed or wild plants that may also exhibit disease symptoms. If observed, that plant material should also be removed to reduce disease buildup.Crop Rotation and Disease-Resistant Cultivars
This year’s wet and humid growing season allowed many insects and diseases to flourish. In preparing for next year, it is essential to maintain good field sanitation. If specific diseases wiped out certain crops, take the time to look for disease resistant cultivars that may be better options for next year. Incorporate crop rotation into your production planning. This can be tricky on small or micro-sized farms, but doing so can minimize exposure to plant pathogens that may have overwintered. Lastly, if you are using tunnels, greenhouses or other season extension structures, don’t forget to keep a close eye on disease symptoms in these environments. Cull diseased plants as soon as they are identified, and survey overwintered plants closely before spring plantings.
These simple steps can go a long way in helping reduce overall pest pressure as a new growing season unfolds.They are part of a farm's larger system utilizing Integrated Pest Management (IPM).
