Spring has sprung in Windsor and Essex County, and as your garden awakens, it’s the perfect time to put in place a plan to protect your prized boxwood shrubs from common boxwood pests. A proactive, seasonal approach is key to preventing infestations and ensuring your boxwoods remain healthy and vibrant all year long. The Spider Guys have put together this month-by-month guide to help you keep your boxwoods looking their best.
Early Spring (March – April): The Awakening and Early Monitoring
- Assess Winter Damage: Take a close look at your boxwoods after the harsh winter months. Note any signs of winter burn (browning foliage) or broken branches. Prune away any dead or damaged growth to improve air circulation, which can help prevent fungal diseases.
- Dormant Oil Application (Late March/Early April): Consider applying dormant oil to smother overwintering boxwood scale insects and boxwood mites before they become active. Follow product instructions carefully and apply on a mild day when temperatures are above freezing and there is no rain in the forecast.
- Initial Pest Monitoring: Begin to keep an eye out for early signs of pest activity. Look for any unusual discoloration, cupping leaves (potential boxwood psyllid), or the very beginnings of webbing (could indicate early boxwood worms).
Late Spring (May – June): Targeting Emerging Pests
- Boxwood Leafminer Watch: Be vigilant for the emergence of adult Boxwood Leafminer flies (small, orange-yellow) typically in May. If you had issues last year, consider applying a systemic insecticide according to product instructions after the adult emergence but before egg-laying. You can also prune and destroy any leaves with noticeable blisters.
- Boxwood Psyllid Control: Inspect new growth for cupped leaves and white, waxy residue. Pruning affected tips can remove many of the nymphs. For heavier infestations, insecticidal soap or horticultural oil can be effective.
- First Generation Box Tree Moth (Boxwood Worms): The first generation of boxwood worms typically hatches in spring. Regularly inspect the undersides of leaves for small, pale yellow eggs laid in clusters. Look for early signs of feeding and small caterpillars. Handpicking and destroying eggs and larvae can be effective for small infestations. Consider a targeted application of Bacillus thuringiensis kurstaki (BtK) if you see caterpillars.
Summer (July – August): Peak Activity and Continued Vigilance
- Second and Possibly Third Generation Box Tree Moth: Continue to monitor for boxwood worms. Multiple generations can occur throughout the summer in Southern Ontario. Regular inspection and prompt action are crucial to prevent significant defoliation. Consider professional boxwood spray treatments for effective control.
- Boxwood Spider Mite Monitoring: Hot, dry weather favors boxwood mite infestations. Regularly check the undersides of leaves for stippling and the presence of tiny mites or fine webbing. Increase humidity by occasionally spraying the foliage with water. If populations are high, horticultural oil or insecticidal soap can be used, ensuring thorough coverage.
- Scale Monitoring: Continue to monitor for boxwood scale. If you didn’t apply dormant oil, target the crawler stage with horticultural oil according to product instructions.
Fall (September – October): Preparing for Winter and Overwintering Pests
- Final Pest Checks: Conduct a thorough inspection of your boxwoods for any remaining pest activity. Address any lingering infestations before winter sets in.
- Sanitation: Clear away any fallen leaves and debris from around the base of your boxwoods. This can help remove overwintering sites for some pests and reduce the risk of fungal diseases.
- Winter Protection: Ensure your boxwoods are adequately watered before the ground freezes. Consider anti-desiccant sprays to help prevent winter burn, especially on young or exposed plants.
Winter (November – February): Dormancy and Planning
- Minimal Intervention: During the dormant season, avoid pruning unless it’s to remove dead or damaged branches.
- Review and Plan: Take this time to reflect on the past growing season. Did you have significant pest problems? Research effective strategies for the upcoming spring and consider scheduling preventative pest control in Windsor services with The Spider Guys.
Protecting Your Boxwoods is a Year-Round Commitment:
By following this seasonal plan and staying vigilant, you can significantly reduce the risk of damaging boxwood pests and keep your shrubs healthy and beautiful. Remember, early detection and prompt action are key to successful boxwood pest control.
If you encounter persistent pest problems or need professional assistance with boxwood spray applications or identification, don’t hesitate to contact the experts at The Spider Guys. We are dedicated to providing effective pest control in Windsor and surrounding areas. For more information on identifying specific boxwood pests, be sure to read our blog: A Homeowner’s Guide to Diagnosing and Treating Common Boxwood Issues.
Protecting your boxwoods is our priority. At The Spider Guys, we are committed to helping you keep your Southern Ontario landscape healthy and beautiful. If you suspect a pest infestation on your boxwoods, don’t hesitate to contact us for expert identification and effective management solutions. We have the knowledge, experience, and tools to protect your valuable plants. For more expert advice, explore our other blog posts on boxwood pests.