Why are my window box herbs dying?
Written by
Michael Sullivan
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Recognizing the key symptoms is essential to the proper diagnosis of ailing window box herbs. Yellow leaves frequently indicate a root problem, such as over-watering, while wilting indicates a lack of moisture. Leggy growth suggests a lack of light. Pest problems indicate a lack of circulation. Each of these ailments results from specific diseases or conditions, which must be addressed with targeted remedial measures.
Overwatering remains the leading cause of death for container herbs. Wet roots suffocate, resulting in yellowing leaves. Mediterranean herbs suffer the most because they like dry weather. Be sure to check the soil's moisture level before watering. Be sure to keep the drain holes cleared of debris so the excess water can escape.
Underwatered herbs have a dramatic wilting with crispy leaves. Rootbound plants can react similarly, with roots choking themselves. If plants dry up too quickly, check their root mass. Transplant them into larger boxes at once if the herbs are crowded. Mulch the soil surface to help retain moisture for longer periods.
Yellow Leaves
- Cause: Overwatering or blocked drainage
- Solution: Reduce watering frequency by 50%
- Clear drainage holes with pipe cleaner
- Repot using grittier soil mix
Wilting Plants
- Cause: Underwatering or root-bound plants
- Solution: Water deeply until drainage flows
- Transplant to larger container
- Add water-retentive crystals to soil
Leggy Growth
- Cause: Insufficient sunlight
- Solution: Move box to sunnier location
- Supplement with grow lights 6 hours daily
- Rotate containers every 3 days
Pest Infestations
- Cause: Poor airflow around plants
- Solution: Increase spacing between herbs
- Apply neem oil spray weekly
- Install box further from walls
Prevent recurrence through proactive measures - monitor plants weekly for early warning signs. Water Mediterranean herbs only if the soil feels bone dry. Check roots for density each season. Maintain a spacing of 4 inches between plants. These habits help prevent problems before they occur.
Seasonal adjustments will help reduce environmental stress. If possible, provide afternoon shade during heat events in the summer. Burlap wraps on the outside of your boxes offer some shielding from the winter winds. Watering needs can change with temperature fluctuations, so be mindful of adjusting your watering frequency accordingly. Consistent and careful monitoring allows you to have great herbs annually.
Read the full article: 10 Best Window Box Herbs for Your Kitchen
