How often should orchids be fertilized?

Written by
Michael Sullivan
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Appropriate timing of applying fertilizers enables orchids to bloom repeatedly without damaging their roots; overfeeding can burn the roots, while underfeeding can restrict the number of blooms. Orchids are only active and therefore require nutrients during periods of active growth. This guide provides recommended fertilizer schedules based on research to help you grow healthy, vibrant orchids.
Formula Selection
- Urea-free formulas prevent root tip burn
- Balanced 20-20-20 NPK during vegetative growth
- Bloom-boosting 10-30-20 before flowering
- Organic alternatives like fish emulsion work
Solution Preparation
- Quarter-strength dilution protects sensitive roots
- Distilled water prevents mineral interactions
- pH adjustment to 5.5-6.5 range
- Temperature matching to plant environment
Seasonal Timing
- Active growth phases: Monthly feeding
- Dormancy periods: Complete suspension
- Bloom initiation: Extra phosphorus
- Post-flowering: Recovery nutrition
Salt accumulation prevention. All pots should be flushed quarterly. Pure water should be run through the pots for five minutes every month. This will wash out the excess fertilizer that would otherwise remain and build up. I set aside flush days for the first weekend of each season, so your orchids do not have to contend with damaging mineral deposits.
Dormancy periods require you to stop feeding. Many orchids rest for 6 to 10 weeks after flowering. To fertilise at this season is to throw good food away and injure your plants. I do not feed again until new roots or leaves are forming. Your plants will produce fruit more effectively if you follow the same plan.
Modify your feeding plan according to the frequency of blooming. Orchids that bloom twice a year likely need more calories. If your leaves are darkening or the tips are browning, reduce the amount of feed. I keep track of when my orchids bloom and respond to their feeding needs. Your customized feeding plan will adapt as you make observations.
Read the full article: Best Soil for Orchids: Expert Guide