How to Fertilize Herbs
Less is more - herbs prefer lean conditions for maximum flavor
Don't Over-Fertilize Herbs!
Unlike vegetables, most herbs produce stronger flavors when slightly stressed. Too much fertilizer causes rapid, weak growth with diluted essential oils. When in doubt, fertilize less.
Quick Reference
Fertilizing by Herb Type
Mediterranean Herbs (Very Light Feeding)
Rosemary, Thyme, Oregano, Sage, Lavender
These herbs naturally grow in poor, rocky soil and need almost no fertilizer. A light topdressing of compost once a year is plenty. Too much fertilizer weakens plants and reduces flavor.
Leafy Herbs (Light-Moderate Feeding)
Basil, Parsley, Cilantro, Dill, Chives
These grow faster and can handle monthly feeding with diluted fertilizer. Still keep it light - half-strength balanced fertilizer. Basil is the hungriest of this group.
Vigorous Herbs (Moderate Feeding)
Mint, Lemon Balm, Chervil
These aggressive growers can handle regular feeding every 2-3 weeks. Mint especially will happily absorb whatever you give it - but it doesn't need it to thrive.
Individual Herb Guidelines
Basil
Hungriest common herb. Feed every 2-4 weeks with diluted balanced fertilizer. Pinch flowers to keep leaves producing.
Rosemary
Rarely needs fertilizer. One light feeding in spring is enough. Excess nitrogen causes weak, floppy growth.
Cilantro
Light feeder. Feed every 3-4 weeks. Too much nitrogen speeds bolting. Keep cool and don't overfeed.
Thyme
Prefers poor soil. Annual compost topdressing is sufficient. Over-fertilizing reduces essential oils.
Parsley
Moderate feeder (for an herb). Feed monthly with diluted fertilizer. Benefits from nitrogen for leaf production.
Mint
Will grow in almost anything. Light monthly feeding keeps it healthy but isn't essential. Grows aggressively regardless.
Container vs. In-Ground Herbs
In-Ground Herbs
- • Add compost when planting
- • Annual compost topdressing
- • Rarely need additional fertilizer
- • Soil provides steady nutrients
Container Herbs
- • Use quality potting mix with compost
- • Feed every 2-4 weeks (diluted)
- • Nutrients wash out with watering
- • Watch for yellowing leaves
Frequently Asked Questions
Do herbs need fertilizer?
Most herbs are light feeders and need minimal fertilizer. In fact, too much fertilizer reduces flavor intensity. Monthly feeding with diluted fertilizer is usually plenty.
What's the best fertilizer for herbs?
Use a balanced, diluted fertilizer (like 10-10-10 at half strength) or organic options like compost tea or fish emulsion at half strength. Less is more with herbs.
Why do my herbs have weak flavor?
Over-fertilizing causes rapid, lush growth with reduced essential oils (flavor). Cut back on fertilizer and let plants grow slower for more intense flavor.
Should I fertilize herbs in containers differently?
Container herbs need slightly more frequent fertilizing than in-ground herbs since nutrients wash out. Feed every 2-3 weeks with diluted fertilizer.