PRO-MIX HP MYCORRHIZAE Open Top Grow Bag | 0.5cu ft - Loose Fill Open Top Grow Bag

Ready-to-Plant High-Porosity Grow Bag, 0.5cu ft

Filling individual containers with loose growing medium takes time that a lot of growers would rather spend elsewhere during a busy planting window. PRO-MIX HP Mycorrhizae Open Top Grow Bags solve that by putting a high-porosity medium directly inside a bag that doubles as the container: fibrous Sphagnum peat moss and a high percentage of coarse perlite for air porosity and low water retention, enhanced with AGTIV Reach beneficial endomycorrhizae, with a tear-off top and pre-cut drainage holes so growers open the bag and plant straight into it.

This 0.5cu ft open top grow bag is sized for a single small to medium container planting, letting growers try the format before committing to a larger size.

Key Features & Benefits

• Tear-Off Top Opening — opens quickly for direct planting without needing a separate container.
• Pre-Cut Drainage Holes — built-in drainage saves setup time versus punching holes in a plain bag.
• High-Porosity Peat and Perlite Blend — delivers strong air porosity and low water retention, adapting to varied crop cycles.
• AGTIV Reach Endomycorrhizae — beneficial endomycorrhizae that support stronger root systems and improved nutrient uptake.
• Reduces Water-Related Issues — the porous, well-drained fill helps limit the algae, fungus gnats, and standing-moisture problems that come with slower-draining media.

Who Should Use PRO-MIX HP Mycorrhizae Open Top Grow Bags

These bags fit professional greenhouse and nursery growers producing vegetables, herbs, or flowering plants who want a ready-to-plant, mycorrhizae-enhanced medium without a separate container-filling step.

About PRO-MIX

Premier Tech introduced PRO-MIX in 1968 on top of a peat-substrate business dating to 1923. The AGTIV Reach mycorrhizal inoculant blended into these grow bags is produced at the company's own biotechnology lab.

Frequently Asked Questions

What does AGTIV Reach add to this medium?

AGTIV Reach is Premier Tech's beneficial endomycorrhizae, blended in to support stronger root systems and improved nutrient uptake. It's already incorporated into the bag's fill, so no separate inoculation step is needed.

Is this bag ready to plant?

Yes, open the tear-off top and plant directly into the bag rather than transferring the medium into a separate container. The pre-cut drainage holes are already in place.

What growing conditions is this medium suited for?

Its high perlite content gives it strong air porosity and low water retention, which suits crops that need consistent drainage or growing conditions like low light or high humidity where excess moisture is a bigger risk. Water-sensitive crops and rooting cuttings both benefit from that drainage profile.

How does a grow bag differ from a loose fill bag of the same formula?

A grow bag serves as both the medium and the container, with a tear-off top and drainage holes built in for direct planting. A loose fill bag, by contrast, is meant to be emptied into a separate pot or tray rather than planted into directly.

What sizes are available?

This grow bag format is available in 0.5cu ft and 1cu ft sizes. Growers can match the bag to a smaller container-scale planting or a larger single-plant setup.