Add carbon-rich material (“browns”)
Help create structure in compost
Because shells decompose slowly, smaller pieces break down faster.
2. Use as Mulch
Crushed shells can be spread around plants to:
Reduce weed growth
Help retain soil moisture
Provide a decorative surface layer
3. Improve Soil Texture
Small amounts mixed into soil may help create air pockets and improve drainage in some garden beds.
⚠️ Things to Keep in Mind
Pistachio shells decompose slowly.
They are not a major source of nutrients compared with compost or fertilizer.
Avoid using large quantities of salted shells without rinsing them first.
🚫 Common Myth
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