March weather is always unpredictable, however, if we have sustained periods of increased temperatures and spring rains, boxwood blight (BWB) will become an issue quickly.
New – [pictorial tri-fold] Common Boxwood Pests and Diseases (click-here). This includes Box Tree Moth images. Print the PDF out double-sided, then fold. We are working to have a better resolution print of this material very soon.
If you suspect Boxwood Blight and would like to have this verified – please contact the Rutgers Plant Diagnostic Laboratory (click here) for sample submission instructions
| Boxwood Blight Risk Assessment as of 3/4/2025 | |||||||||
| Region | Location | CODE | 3-March | 4-March | 5-March | 6-March | 7-March | 8-March | |
| Southern | Upper Deerfield | NJ50 | Very Low | Very Low | Low | Minor Risk | Very Low | Very Low | |
| Central | Howell / Freehold | NJ10 | Very Low | Very Low | Low | Minor Risk | Very Low | Very Low | |
| Northern | High Point | NJ59 | Very Low | Very Low | Very Low | Minor Risk | Very Low | Very Low | |
| M | T | W | TH | F | S | ||||
| Please check YOUR LOCAL risk (click here) | |||||||||
There is a minor potential for boxwood blight infections this Wednesday & Thursday, throughout ALL of NJ. Incoming rains, coupled with warmer temperatures may initiate boxwood blight infections this week.
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It is time to begin protective fungicide applications in boxwoods throughout the state if you have not already done so.
- If BWB is important to your business – Use the USPEST – PUSH Alerts – (click here) – to setup weekly email alerts. Create an account, watch the tutorial, and then set up your subscriptions. You select which locations (as many as you like), days you want to receive emails, and what you would like to receive alerts about (BWB and a variety of other pests and diseases). Rutgers is not directly affiliated, however this is an incredible tool.
These advisories are general in nature, change rapidly over time, are site-specific…therefore Someone from your business should be using this risk model daily if boxwood is important to your financial stability– In 30 seconds you can have a better idea of boxwood blight (and other pathogens) activity in your immediate area! Please contact Tim Waller if you need help using this service (twaller@njaes.rutgers.edu), we want to help!
- If your area is not listed (throughout all of NJ please visit the USPEST.ORG Boxwood Blight Risk Model – CLICK HERE TO CHECK YOUR LOCAL PREDICTIONS)
Fungicides;
- You very well may have these materials already applied as ‘cover-sprays’ – But – be mindful that protectant fungicides loose efficacy the more rain (or overhead irrigation) they are subjected to, and reapplication may be warranted.
- ROTATE between Fungicide Resistance Action Committee (FRAC codes) to avoid this pathogen becoming resistant to specific chemicals
Format: [FRAC code]: Chemical name (Trade names * no endorsement implied, other options exist)
- [M05]: Chlorothalonil (Daconil WS)
- [M05 + 1] Chlorothalonil + Thiophanate methyl (Spectro 90WDG)
- [11] Trifloxystrobin + [7] Fluopyram (Broadform)
- [11] Trifloxystrobin + [3] Triadimefon (Armada 50WDG)
- [M03] Mancozeb
- [12] Fludioxonil (Medallion WDG)
- [3] Tebuconazole (Torque)BW
DISCLAIMER: The label is the law, always refer to it for allowable host crops, use-restrictions, application rates, reapplication intervals, re-entry intervals (REI), and mix compatibility information. Production and pesticide information on this site are for private/commercial pesticide applicators and landscape professionals only, and are NOT for home gardener use. Provided materials represent examples and do not cover all possible control scenarios. Trade-names listed do not imply endorsement and are used as examples only. Please contact your local agent or chemical sales representative for more information or to discuss additional pest management options.
Boxwood Resources
- CLICK HERE FOR 2020 – Boxwood blight resistant cultivar rankings (USDA).
- Click here for additional BWB research updates
- CLICK HERE FOR A FREE DOWNLOAD – BOXWOOD HEALTH, Best Management Practices Production and Landscape Management (18 pages – Version 3.0)
- Click here for more BWB initiatives
Background on Boxwood Blight pathogen:
Box Tree Moth – Resources:
- Video: Click here for- “Demystifying Box Tree Moth” – HRI
- Factsheet: Box Tree Moth: Fact Sheet, Management & Visual Guide
- OSU Guide: What to look for with Box Tree (Boxwood) Moth
- USDA-APHIS Box Tree Moth : APHIS BTM Landing page
- Compliance agreement and information: National Plant Board – Box Tree Moth
- HRI VIDEO – “Box Tree Moth Compliance Agreement Explained”
