Raw unsterilised grain — ready to hydrate, sterilise and inoculate at home. This is bulk raw wheat grain for growers who prepare their own grain spawn. If you're looking for ready-to-use sterilised substrate, see our All-in-One Substrate Bags instead.
When you need the performance of a premium grain substrate without the price tag of rye, organic wheat grain is the answer. High in starch, with excellent moisture retention and a solid nitrogen profile, wheat berries produce fast, vigorous colonisation — making them a practical choice for both beginner growers and established operations running high volumes of substrate.
At $8.50/kg raw, wheat costs a fraction of pre-sterilised bags on the Australian market — and at bulk quantities, the economics improve further. Add multiple kilograms to cart for automatic bulk pricing at checkout.
Why wheat grain belongs in your rotation
Wheat grain occupies the sweet spot between millet and rye. It provides a higher inoculation point density than rye (more, smaller grains per kilogram) while offering a more substantial nutrient base than millet. The starch content is high — an explosive energy source for mycelium that often produces faster run times than rye on equivalent substrates.
Organic wheat is also the most cost-effective high-quality grain option in the range. For growers running large volumes of oyster, Lion's Mane, or Shiitake cultivation — where substrate costs need to stay controlled — wheat is the grain that makes the economics work without compromising colonisation quality.
As with all our grain, this wheat is 100% organic and free from the fungicides commonly applied to agricultural feed grain. Fungicide-treated grain is a well-documented cause of failed inoculations — it's a risk that simply doesn't exist with food-grade organic wheat.
Best suited to
Excellent across the full range of gourmet species — oysters of all varieties, Lion's Mane, Shiitake, and Pioppino. Particularly well-suited to high-volume grows where cost control matters: oyster production at scale benefits significantly from wheat's combination of fast colonisation and lower per-kilogram cost versus rye. Also an excellent choice for Masters Mix supplemented hardwood grows.
Preparing your grain
Hydration: Rinse thoroughly, then simmer in water for 15–20 minutes until berries are fully hydrated and tender — the grain should swell visibly, remain intact, and show no hard white core when cut. Drain well, then surface-dry on a clean tray for 30–60 minutes. Like rye, over-hydrated wheat is a contamination risk — aim for field capacity: no surface moisture, a dull surface rather than shiny.
Sterilisation: Load into mason jars or filter-patch spawn bags, leaving 20–30% headspace. Sterilise at 15 PSI (121°C) for a minimum of 90–120 minutes. Allow pressure to drop naturally before opening. Cool completely before inoculating.
Spawn rate: 10–20% by weight into your bulk substrate. 1KG of finished grain spawn will inoculate approximately 5–10KG of bulk substrate depending on species and substrate type. Wheat works particularly well in supplemented hardwood substrates where its high starch provides a complementary nutrient profile.
The Kai Kai Farm difference
100% organic, food-grade wheat — the same standard we apply to every input across our own commercial production. No fungicide residues, no feed-grade agricultural chemicals. Clean, reliable grain for clean, reliable results. Packed on our Tamborine Mountain farm. Add multiple kilograms to cart to access bulk pricing automatically at checkout.
