HP - high porosity

PRO-MIX HP provides a great growing environment to growers looking for a significant drainage capacity, increased air porosity and lower water retention. The added benefit of fibrous peat moss and coarse perlite makes this formulation ideal for growers who require a superior-quality product adapted to their needs for watering flexibility and crop seasonality.

Learn more about the Open Top Grow Bag here

Where to find our products

Questions to our experts


  • Medicinal Plants
  • Berries


  • Dries out more frequently than general purpose, peat-based mixes
  • Well suited for low-light growing conditions and high humidity
  • More difficult to overwater crops
  • Reduces incidence of water related problems (root diseases, algae and fungus gnats)
  • Holds less water for improved leaching of fertilizer salts during crop cycle

Active Ingredients


  • Protect and enhance plant growth
  • Most advanced technologies in active ingredients
  • Saves time and money

Advice from our specialist

What's the difference between PRO-MIX BX and HP?

PRO-MIX BX is a general-purpose growing medium, compared to PRO-MIX HP which is a High Porosity growing medium. These products are the same in pH and chemical properties.  The difference is that PRO-MIX HP contains a higher percentage of perlite than PRO-MIX BX. Perlite is a porous aggregate that does not absorb water.

When incorporated into growing media, perlite provides air porosity and reduces water retention. Since PRO-MIX HP contains a higher percentage of perlite than PRO-MIX BX, HP holds less water and is better suited for crops that are sensitive to overwatering, to low light growing conditions or for use in winter months when daylight is shorter.

What is the pH of PRO-MIX HP?

Using the Saturated Media Extraction test method (SME), PRO-MIX HP is formulated in a pH range of 5.2-6.2. Once the product is opened, crops planted and watered, limestone is activated and pH will reach 5.8-6.2 within 7-10 days.  

Can you reuse PRO-MIX HP?

We do not recommend re-using PRO-MIX HP or any growing medium. There are many good reasons to not recycle, among these include changes to chemical and physical properties over time when in use, the diminished effect of the wetting agent after use and/or transmission of root diseases to newly planted crops.

When to water PRO-MIX HP?

When irrigating, add water to PRO-MIX HP until it is saturated from top to bottom. You will know you have accomplished this when water runs out of the drainage holes at the bottom. Over time, allow the growing medium to dry out without applying additional water.

You will know when to apply water again when the surface of the growing medium turns from a dark brown/black (wet) to a light brown/tan colour (dry enough to rewater). 

Does PRO-MIX HP have nutrients?

Yes, PRO-MIX contains a starter fertilizer to help plants acclimate to a new rooting environment. We strongly recommended initiating a fertilizer program within 7-10 days after planting. The fertilizer program you select should take into consideration water quality, crop type and the stage of plant growth.

Is PRO-MIX HP soilless?

PRO-MIX HP is a peat-based growing medium formulated with a high percentage of perlite. PRO-MIX HP and all PRO-MIX growing media products are 'soilless', meaning that they do not contain any mineral soil. 

See more

Training center


  • SPHAGNUM PEAT MOSS (65-75%) ?

    Canadian Sphagnum peat moss is a natural, organic matter that comes from a peat bog. This primary resource is carefully harvested by vacuum harvesters. Peat moss comes in various fibrosity and levels of decomposition. Once carefully graded, peat moss assures that qualities of each grade are optimized for based on grower and uses for a final product reaching high quality requirements.


    Perlite is an alumino-silicate ore of volcanic origin. The raw ore is crushed, graded and screened in various particle sizes. Perlite has a high total-porosity and improves drainage and air porosity.


    Used to adjust pH to optimum range. Also a source of Calcium and Magnesium.


    A wetting agent is a substance that reduces the surface tension of water, allowing water to penetrate and uniformly wet growing media.


    Tecnología PTB180, Bacillus pumilusBacillus es una bacteria que asegura una zona radicular sana. Como colonizadora de la raíz, estimula a la planta para un crecimiento más eficiente.


    PTB297 Technology, Glomus intraradices - Mycorrhizae are beneficial associations between a mycorrhizal fungus and roots, creating a network of filaments that explores the soil and access more nutrients and water, and transfer them to the plant.

Documents and specifications

Code Size (Regional availability may vary) Units per pallet Weight
2005700RG 0.5 cu ft Loose 294
2010700RG 1.0 cu ft Loose 135
Size (Regional availability may vary) 0.5 cu ft Loose
Units per pallet 294
Size (Regional availability may vary) 1.0 cu ft Loose
Units per pallet 135

Your 2021 season full package

Get full access to all the information you need to start the season on the right foot.

Customer Service / Sales:
1 855 867-5407

Grower Services:
1 800 424-2554