US: Investing in your future of Spider Mite control

As we head into the autumn season, declining temperatures and daylight levels help to push the Two-Spotted Spider Mite into hibernation. Many of you will be familiar with the red-coloured inactive stage of the common pest, and be relieved about its arrival. The truth is, although hibernating spider mites do not feed or reproduce, they are mated females that are ‘hibernating’ until favourable conditions return to the greenhouse. This means in the spring, the females that have crawled into small cracks and hiding spots in the floor for the winter can quickly re-establish in your crop and cause a sudden explosion of pest activity. Fortunately, by planning ahead and making some educated, smart decisions, you can prevent the spring surprise!

Often near the end of a crop cycle in vegetable greenhouses, a grower will either choose to “give up” on spider mite control and focus on clean-up activities, or they will choose to spray a harsh chemical meant to kill all remaining insects (including beneficial insects). Although a thorough clean-up is necessary, and ridding a greenhouse of all pests is essential to start a new clean crop, spraying harsh chemicals will not affect hibernating spider mites. A crop advisor or technical representative from your biocontrol supplier can help determine whether spraying a harsh chemical is absolutely necessary at the crops’ end. If it is determined that your pest population is below a threshold for which harsh chemicals should be applied, we recommend you invest in some Phytoseiulus persimilis. Applying persimilis at the end of your crop will cost less than a chemical application, and will help to eradicate all forms of spider mites present, without a build-up of chemical resistance. Consider this an investment in your future. By applying persimilis now, you will avoid a potentially large outbreak of the pest in your next crop, saving you money down the road.

For more information:
Crop Defenders
Mary Xavier
150 Fraser Road
Leamington ON N8H 4E7 Canada
mary@cropdefenders.com
www.cropdefenders.com