Aged Horse Manure Compost for Mushroom Cultivation

Screened, sun‑dried horse manure blended with stable bedding straw. Fully aged and turned to reduce ammonia, it provides the balanced nitrogen, fibre and microbial profile favoured by button, portobello and other compost‑loving mushrooms.

Why Horse Manure?

• Natural NPK balance (≈ 1‑1‑1) plus humic acids for robust pin sets and dense caps.
• Fibrous texture holds moisture while staying airy—ideal for deep beds or monotubs.
• Aged ≥ 6 months then heat‑treated to lower weed seeds and pathogens.
• Mild earthy scent, far less odour than fresh manure.

Recommended Use

• Compost beds (Agaricus spp.) : 60‑70 % horse manure, 20‑30 % straw, 5‑10 % gypsum. Pasteurise at 60‑65 °C for 1 hour.
• Bulk substrate supplement : Add 10‑15 % (wet weight) to straw or coir mixes for oysters or shaggy ink cap. Pasteurise with the bulk.

Preparation Steps

1. Hydrate to field capacity (squeeze test: one to two drops of water).
2. Thoroughly mix with straw or coir if using as part of a blend.
3. Pasteurise 60‑65 °C for 60 minutes, cool below 27 °C, then inoculate.

Pack Size

100g dehydrated, crumbly compost in a breathable paper‑lined pouch—expands to roughly 300 mL when re‑hydrated.

Tips

• Monitor core temperature during pasteurisation; do not exceed 70 °C or nutrients may caramelise.
• Vent monotubs well—horse‑based compost generates more CO₂ than coir mixes.
• Store pouch cool and dry; re‑wet only what you need for a single batch.

Legal & Safety

For cultivating legal mushroom species only. Wear gloves and a dust mask when handling dry compost. Not for direct animal or human consumption. Keep out of reach of children and pets.