Boomer Shroomer Dry Bulk Substrate for Mushroom Cultivation | 10 lb Pasteurized Substrate for Two Monotubs | Mushroom Substrate

Overview

Boomer Shroomer Dry Bulk Substrate is designed to support reliable mushroom cultivation with a balanced CVG blend. The dry mix combines coconut coir, vermiculite, and gypsum in precise proportions to create a substrate that can hydrate smoothly, maintain moisture, and provide a stable base for your monotub or tray setups. This is a practical option for growers who want a straightforward, scalable path from dry mix to fruiting stages.

What’s included

The kit features three core components in measured amounts to simplify preparation. The coconut coir delivers texture and water-holding capacity, vermiculite contributes air pockets for gas exchange, and gypsum helps stabilize the mixture as it hydrates. This combination aims to offer a consistent starting point for a range of cultivation projects.

• Premium CVG bulk substrate blend tailored for consistency across batches
• One easy to hydrate mixture designed for single-step water addition

How to prepare

Hydration is a straightforward step in a standard kitchen or workshop setup. In a 5-gallon bucket, add 16 cups of boiling water to the dry mix. After mixing, pasteurize the substrate for 24 hours to reach a stable field capacity. Allow the mixture to cool before introducing spawn as part of your cycle.

• Use boiling water for predictable hydration
• Pasteurize for 24 hours to reduce contaminants and establish stability
• Cool before proceeding with spawn-to-bulk transfers

Yield and versatility

When hydrated, the dry mix yields about 9 lb of substrate, enough for two full monotub grows or other fruiting configurations. This makes it a practical choice for growers planning multiple flushes or experimenting with different setups.

Why the blend works

The combination balances moisture retention with aeration. Coconut coir holds moisture, vermiculite adds air pockets, and gypsum stabilizes pH and structure. The result is a substrate that can support consistent mycelial activity across stages without requiring complex adjustments.

• Strong moisture retention helps prevent premature drying between tasks
• Air pockets support gas exchange during colonization
• Gypsum provides structure and contributes to pH stability

Who it’s for

Whether you are new to spawn-to-bulk transfers or an experienced grower exploring monotub setups, this substrate is designed to be approachable and reliable. It works well with monotubs, trays, and filter bags, with clear steps to integrate into your process.

Have questions or need guidance? The Boomer Shroomer team is available at [email protected] for support and advice.