Starting with the COVID pandemic, corporations and other businesses are price gouging. The current ridiculously high cost of gasoline comes as oil companies are raking in tens of billions of dollars in profits.

And you know who else is price gouging? People who make and market grow op supplies to marijuana growers.

One of the most noticeable areas of price gouging is in commercial soil, coco coir, and soilless mix.

Prices have doubled or tripled online and at local grow stores. Part of this is because shipping is more expensive due to elevated fuel prices.

The other problem is that many soil brands, especially Fox Farm, are poorly made. They usually have unreliable pH buffering and nutrients loads, and sometimes come with root aphids, fungus gnats, and plenty of filler.

Fox Farm and similar soil brands are still relatively inexpensive compared to professional brands like Fertilome, because they’re selling you scraps, bark, and amateurish mixes that are inconsistent from batch to batch.

I used to throw away my root zone media after each grow. That was when three cubic feet of clean, aerated media perfect for growing cannabis cost $15. Now it’s $57, and if I order it online, the shipping costs more than the media.

I asked the soil, coco coir, and soilless mix companies if I should reuse their products. Of course they said no—it wouldn’t be good for their profits if they said yes.

They claim that reusing soil creates risk of soil-borne diseases, pests, and nutrients problems, but after I started reusing root zone media, I found you can save a lot of money by properly processing your media and using it over and over.

Here’s how it works…

  • Contrary to hydroponic marketing memes, flushing your root zone in the last days of bloom phase has zero benefits for harvest weight, taste, or crop quality and actually harms your marijuana growing outcomes. But flushing after the end of bloom phase using pH-adjusted reverse osmosis water, horticultural enzymes, and beneficial microbes like TPS Billions cleans your root zone of excess nutrients salts.
  • After you’ve flushed your used soil, coco coir or soilless mix, spread it out on a raised grow table or other place with a lot of surface area in a clean environment with low humidity and no contaminants.
  • Comb through the media to remove all root fragments from previous crops.
  • Examine the media with magnification and bright light to detect pests.
  • Treat the media with an ultraviolet sterilization device.
  • Turn the media over frequently until it evenly dries to the same consistency as it was when you first took it out of its container.
  • Store the media in secure bags, in an aerated, climate-controlled, sterile location until you’re ready to use it again. Poke a few small holes in the bag above the media line for bag aeration.

Here are some issues you encounter when you recycle media:

  • If you’re using inferior hydroponic nutrients, they bind to the media and are harder to purge.
  • I dilute my recycled media with new media at a ratio of 50-50 after I have reused the media three times or if I am having problems with media pH or nutrients salts saturation.
  • Check runoff pH and parts per million of your recycled media. If runoff is consistently more than + – 15% out of range compared to input solution, the media needs to be adjusted, diluted with fresh media, or abandoned.
  • Washed, purged media over time loses whatever pH buffers were installed by the manufacturer. Adjusting media pH must be done carefully, and is beyond the scope of this article. Do research as needed. It can be tricky if not sometimes impossible to adjust long-term pH buffering of used media. Check out this video about adjusting media (substrate) pH…
  • Consider adding coarse perlite to recycled media, especially coco and peat-based, which tend to compact and crunch down. Always wash perlite before using and beware of perlite dust, which is toxic.
  • Use quality beneficial microbes like Billions throughout crop cycles. Live compost teas are also helpful.
  • Use enzymes to clean the root zone. Most enzyme products sold in grow shops are just junk in a bottle or bag. The one enzyme product I trust is Hygrozyme. Check with the manufacturer for use instructions—there are unverified reports that Hygrozyme can mess with pH.
  • The most I’ve ever reused marijuana growing media is seven times. I learned to carefully examine structure of media elements to detect physical breakdown. This often happens with recycled coco coir.
  • After I’ve gotten as much use from my old root zone media as possible, I use it in outdoor veggie gardening and for composting as you see in the videos embedded in this article.
  • Start with the highest quality root zone media possible. Price should not be your main consideration—professionally made, properly pH-balanced, filler-free traits should be your baseline.
  • Whenever possible, get root zone media that contains no starter fertilizer charge.

The grow shops tell me the price of root zone media will never go back down to what it was. I always felt bad throwing away soil, coco coir and soilless mix after each season, but had been brainwashed into thinking cannabis growing media went bad after one use.

Now that I’m recycling root zone media for marijuana growing, I’m reducing waste, and saving a lot of money. You can too!