Wheat Straw Substrate | 2.5 kg Bag

Wheat straw is the cornerstone of low-cost, high-yield mushroom cultivation. Our 2.5 kg bag delivers clean, pre-chopped dry wheat straw sourced directly from regional European farmers and screened for foreign material. The straw is supplied raw and dry — not pre-pasteurised; you hydrate and pasteurise it yourself at home before inoculation. Pasteurising fresh just before use is the standard and the most reliable way to grow on straw.

How it ships

• Raw, dry, unpasteurised — the bag contains dry chopped straw, ready for you to hydrate and pasteurise at home
• Not sterile, not pre-treated — no heat, chemicals or moisture treatment have been applied
• Why we ship it dry and raw — pasteurised straw must be inoculated within 24 hours, so shipping pre-pasteurised straw is impractical. You get fresh, dry straw with a long shelf life and pasteurise it the day you inoculate.

Product specifications

• Net weight: 2.5 kg of dry, raw chopped wheat straw
• Cut length: 2–5 cm chops for optimal pasteurisation and colonisation
• Origin: locally sourced European farmland
• Condition: dry, raw, unpasteurised — pasteurise at home before use
• Expected yield: 2.5 kg dry straw hydrates to roughly 7–8 kg of wet substrate

Which mushrooms grow on wheat straw

Wheat straw is the textbook substrate for straw-loving and dung/compost species. From our own catalogue, the strongest match is Panaeolus cyanescens (Copelandia) — a small but vigorous active species that thrives on a straw + manure mix. We carry it in two Liquid Culture varieties:

• Panaeolus cyanescens 'Hawaii' Liquid Culture — the classic Hawaiian Copelandia
• Panaeolus cyanescens 'Jamaica' Liquid Culture — the Jamaican isolate
• Yellow Umbo Liquid Culture — a related Panaeolus copelandia variety

Prefer a ready-to-grow format? See our Hawaii Copelandia Grow Kit or MIB Copelandia Grow Kit .

Wheat straw is also the textbook substrate for gourmet straw-lovers:

• Pleurotus ostreatus — pearl oyster mushroom
• Pleurotus pulmonarius — phoenix / Italian oyster
• Pleurotus eryngii — king oyster (with supplementation)
• Stropharia rugosoannulata — wine cap / king stropharia
• Coprinus comatus — shaggy mane / inkcap

For Psilocybe cubensis and other manure-loving cubensis species, use a coir-based mix instead: Sterile CVG Substrate Mix .

How to prepare wheat straw

1. Hydrate — soak the straw in clean water for 12–24 hours until fully saturated
2. Pasteurise — heat to 65–82 °C for 1–2 hours (hot-water bath, steamer or insulated cooler)
3. Drain — drain to "field capacity" (a strong squeeze yields a few drops of water)
4. Cool — let the straw cool to 24–27 °C before adding spawn
5. Inoculate — mix with fully colonised grain spawn at a 1:5 to 1:10 ratio by weight
6. Incubate — pack into mushroom bags or trays, keep at 20–24 °C until colonised
7. Fruit — introduce fresh air, humidity and light to trigger pinning

Why pasteurise, not sterilise

Wheat straw has a low nutrient profile, which is exactly why pasteurisation (not full sterilisation) works best. Pasteurising at 65–82 °C eliminates harmful moulds and bacteria while leaving beneficial thermophilic micro-organisms alive — these compete against contaminants and give your mushroom mycelium a head start. Full autoclave sterilisation strips the substrate of all microbes and actually makes contamination more likely on a low-nutrient substrate.

Pair with grain spawn

Wheat straw colonises fastest when paired with active grain spawn. We recommend our sterile spawn bags: Sterile Millet Spawn Bag for fast colonisation or Sterile Sorghum Spawn Bag for larger fruiting yields.

Storage

Store the dry bag in a cool, dry place, away from rodents and direct sunlight. Once hydrated and pasteurised, use within 24 hours for best results.