Soil Mix for Herbs
Different herbs have different soil preferences, but the one universal requirement is drainage. No culinary herb thrives in waterlogged soil. Getting the soil mix right is one of the most important things you can do, especially for container growing and raised beds where you are creating the growing medium from scratch.
General-Purpose Herb Mix
This works for the majority of common herbs — basil, cilantro, parsley, dill, chives:
- 60% quality potting soil (peat-based or coir-based)
- 20% compost
- 20% perlite or coarse vermiculite
This provides a good balance of moisture retention, drainage, and nutrients.
Mediterranean Herb Mix
For rosemary, sage, oregano, and bay laurel — plants that come from rocky, well-drained Mediterranean hillsides:
- 40% potting soil
- 30% coarse sand or pumice
- 20% perlite
- 10% compost
This mix drains very fast and does not hold excessive moisture. These herbs prefer lean soil — too much richness produces lush but weakly flavored foliage.
Tropical Herb Mix
For curry leaves, turmeric, ginger, and lemongrass — tropical plants that like rich, moist (but not waterlogged) soil:
- 40% potting soil
- 30% compost
- 15% perlite
- 15% pine bark fines or coir
This mix holds more moisture and nutrients than the Mediterranean blend while still providing adequate drainage. Add a slow-release fertilizer at planting time for these heavier feeders.
pH Considerations
Most herbs prefer a pH of 6.0–7.0 (slightly acidic to neutral). Curry leaf plants prefer slightly more acidic conditions (5.5–6.5). If you are unsure of your mix's pH, an inexpensive soil test kit from a garden center will give you a reading. Adjust with lime (to raise pH) or sulfur (to lower pH) if needed.
Amending Garden Soil
If you are planting directly in the ground or in a raised bed, amend existing soil with compost (2–3 inches worked into the top 6 inches) and perlite or coarse sand if drainage is poor. Heavy clay soil benefits greatly from the addition of expanded shale or fine gravel. For more on building raised bed soil, see the Raised Garden Bed page.