Wine Cap Grain Spawn

The garden mushroom: grow it outdoors in wood chips.

Two ways to order:

• Made fresh to order (ships in 3–4 weeks): We inoculate your bag after you order, so it arrives fully colonized and at peak vigor instead of aging on a shelf.
• Ready to ship (ships in 1–3 days): When we have a fresh batch on hand, you can skip the wait. If it shows sold out, choose made fresh to order.

Wine Cap (Stropharia rugosoannulata), also called King Stropharia or Garden Giant, is one of the easiest ways to add mushrooms to a garden. It grows outdoors in beds of hardwood chips or straw, breaks that material down into rich, crumbly soil, and produces large burgundy-capped mushrooms with a mild, earthy flavor. It pairs well with vegetable gardens, berry patches, and garden paths.

Plan your timing: Build beds in spring once days are regularly above 50°F, or in late summer to early fall with at least four weeks of warm weather left. Because spawn is freshest within a few weeks of colonizing, order about 3–4 weeks before you plan to build your bed.

Includes WeMush tracking: Every order ships with a QR code linked to WeMush, our cultivation tracking platform. Scan it to view specimen details, log observations, and follow your grow, free with any Mush Ohio purchase.

Specifications

• Species: Wine Cap (Stropharia rugosoannulata)
• Product: Fully colonized grain spawn
• Weight: Approximately 1600 g (about 3.5 lb) wet weight
• Packaging: Filter patch spawn bag
• Coverage: Roughly 15–20 square feet of bed

Building a bed

1. Pick a spot with partial shade that you can keep moist. A north- or east-facing spot works well.
2. Lay down 2–4 inches of hardwood chips (fresh or up to about six months old) or straw, soaked well.
3. Crumble the spawn evenly over the layer, then cover it with another 2–3 inches of chips. Burying grain spawn completely matters, because exposed grain attracts birds and rodents.
4. Keep it moist. Water heavily for the first few days and during dry spells. A layer of cardboard or burlap on top helps hold moisture while the bed colonizes.
5. Top up yearly. Add a fresh layer of chips each year to keep the bed producing.

When and how to harvest

• Timing: Spring-built beds often fruit from late summer into fall of the same year; some wait until the following spring. Established beds typically flush in late spring and again in fall, often after rain.
• Harvest stage: Pick while the cap is still bell-shaped or rolled under and the gills are pale. Quality drops once caps flatten and gills darken.

Safety first: Wild mushrooms can pop up in any outdoor bed, including some look-alikes. Learn Wine Cap's identifying features (a purple-black spore print, a ring on the stem, and no sac at the base), confirm every harvest before eating, and when in doubt, throw it out. Cook mushrooms before eating, and try a small amount the first time. If you garden in an urban yard, consider testing your soil for lead and other heavy metals first.

Storage and handling

• Inspect the bag on arrival for damage or contamination.
• If you can't build your bed right away, refrigerate at 35–40°F (2–4°C).
• For best results, use within 1–4 weeks of receipt.

Bundle and save: Buy four bags of grain spawn and get the fifth free with code BUY4G1FREE. Mix and match any spawn in our Grain Spawn collection.