When to stop harvesting chamomile?
Written by
Tina Carter
Reviewed by
Prof. Charles Hartman, Ph.D.The factors determining when to halt harvesting chamomile are seasonal and related to the type of plant. German chamomile (annual) should be harvested right up until the first hard frost causes damage to plants. Roman chamomile (a perennial) must be cut back a little sooner to prepare for winter and allow the roots to develop. Timing plays a crucial role in determining the quality and longevity of chamomile essential oil.
Frost Preparedness
- Monitor local frost date predictions regularly
- Harvest all open flowers 24 hours before expected frost
- Cover plants with cloth if unexpected frost threatens
Root Strengthening
- Apply potassium-rich fertilizer 8 weeks before frost
- Reduce watering frequency gradually
- Mulch with 3 inches of straw after final harvest
Final Harvest Technique
- Collect flowers in late morning after dew evaporates
- Include slightly immature buds for drying
- Process immediately to prevent oil degradation
Post-Harvest Processing
- Dry flowers within 4 hours of picking
- Store in airtight containers with oxygen absorbers
- Label containers with harvest date clearly
When ice crystals form in the cells of chamomile flowers, the sensitive essential oils are damaged. Frozen flowers will brown, losing their medicinal properties. Always make sure to harvest any remaining flowers before the blooms are forecasted to drop below freezing (<32 degrees Fahrenheit). I pay close attention to the weather in the fall to prepare for a sudden cold snap.
For perennial Roman chamomile, cease harvesting six weeks before the expected frost. This will allow plants to rechannel energy to their roots, building winter resiliency. At this point, use a balanced fertilizer with low nitrogen levels. The hardening-off stage of the plants greatly increases cold tolerance.
Container plants require more attention because their roots freeze quickly. Bring pots indoors when nighttime temperatures drop to around 40°F. Set up grow lights to give the plants 6 hours of daily light. Water very little while plants are in winter dormancy to prevent root rot while the plant rests.
Proper post-harvest storage preserves quality through winter. When flowers have dried completely and pass the crumble test, store them in dark glass containers to avoid light degradation. For best quality keep in cool pantries below 60°F while providing extra care for total potency. Make sure to label jars with harvest dates for best rotation.
Read the full article: How to Grow Chamomile: A Complete Guide
