Subcool’s Super Soil Step-by-Step

There’s nothing that compares to the flavor of properly grown organic pot: The subtle tastes and aromas created by using only “Mother Earth” are overwhelming to the senses when it’s done properly. As with vegetables, a rich organic soil can bring out the best in cannabis.

Over the past 20 years, I have tried almost every possible way to cultivate our favorite plant. And while hydro is certainly faster and the yields blow soil away, I’ve developed an organic-soil mix that consistently performs extremely well, with very little guesswork involved (i.e., I don’t have to worry about pH or ppms ever).

I spent a few years developing the recipe for this Super Soil mix, and using it in 7-gallon nursery pots, I can run from start to finish adding only plain water. Other than a bit of sweat equity every 90 days or so, using this soil takes a huge amount of the science out of gardening and puts nature back in charge. Also, the recipe is always changing in slight ways as I continue to fine-tune it in my efforts to achieve perfection.

The Base

Start with at least six to eight large bags of high-quality organic soil. This is your base soil—i.e., your regular potting soil without the additives. The selection of your base soil is very important, so don’t cut corners here. I can’t begin to discuss all the different products out there, but I will mention a few in this article. A good organic soil should cost you from $8 to $10 per 30-pound bag. Since I want to give you a very specific idea of what I consider to be a balanced soil, take a look at the ingredients in a product called Roots Organic:

Lignite, coco fiber, perlite, pumice, compost, peat moss, bone meal, bat guano, kelp meal, greensand, soybean meal, leonardite, k-mag, glacial rock dust, alfalfa meal, oyster shell flour, earthworm castings and mycorrhizae.

Another local product we’re trying out now, Harvest Moon, has the following ingredients:

Washed coco fibers, Alaskan peat moss, perlite, yucca, pumice, diatoms, worm castings, feather meal, fishmeal, kelp meal, limestone, gypsum, soybean meal, alfalfa meal, rock dust, yucca meal and mycorrhizae fungi.

So far we’ve found that Roots Organic produces a more floral smell in the finished buds, while Harvest Moon generates larger yields.

If you have access to a good local mix like these, then I highly recommend starting with a product of this type. We’ve also had decent results using commercial brands, but never “as is.” The best results we’ve had to date using a well-known commercial soil has been with Fox Farms’ Ocean Forest soil combined in a 2-to-1 ratio with Light Warrior. Used on its own, Ocean Forest is known for burning plants and having the wrong ratio of nutrients, but when cut with Light Warrior, it makes a pretty good base-soil mix.

You can also just use two bales of Sunshine Mix #4, but this would be my last choice, since plants grown in this mix may not respond well to my “just add water” method of growing.

After choosing your base soil, the Super Soil concentrate is placed in the bottom one-third to one-half of the container and blended with the base soil. (With strains that require high levels of nutrients, we’ll go so far as to fill ¾ of the container with Super Soil, but this is necessary only with a small percentage of strains.) This allows the plants to grow into the concentrated Super Soil layer, which means that in the right size container, they’ll need nothing but water throughout their full cycle. One of the things I like best about this soil mix is that I can drop off plants with patients, and all they have to do is water them when the soil dries out.

Stir It Up

There are several ways to mix these ingredients well. You can sweep up a patio or garage and work there on a tarp, or you can use a plastic wading pool for kids. (These cost about 10 bucks apiece and work really well for a few seasons.) Some growers have been known to rent a cement mixer to cut down on the physical labor. Whatever method you use, all that matters in the end is that you get the ingredients mixed properly.

This can be a lot of work, so be careful not to pull a muscle if you’re not used to strenuous activity. On the other hand, the physical effort involved is good for mind and body, and working with soil has kept me in pretty good shape. But if you have physical limitations, you can simply have someone mix it up for you while you supervise. As far as the proper steps go: Pour a few bags of base soil into your mixing container first, making a mound. Then pour the powdered nutrients in a circle around the mound and cover everything with another bag of base soil. In goes the bat poop and then more base soil. I continue this process of layering soil and additives until everything has been added to the pile.

Now I put on my muck boots, which help me kick the soil around and get it mixed up well using my larger and stronger leg muscles instead of my arms. The rest is simple; as my skipper used to say, “Put your back into it.” This is hard work that I obsess over, even breaking up all the soil clods by hand. I work on the pile for at least 15 minutes, turning the soil over and over until it’s thoroughly mixed.

Then I store my Super Soil in large garbage cans. (And before using any of it, I pour the entire load out and mix it well once more.) Once it’s placed in the cans, I water it slightly—adding three gallons of water to each large garbage can’s worth. Though it makes stirring the soil harder, adding water will activate the mycorrhizae and help all the powders dissolve.

Before Planting

So we’ve added the water, and now we let it cook in the sunshine—30 days is best for this concentrate. Do not put seeds or clones directly into this Super Soil mix or they will burn. This is an advanced recipe to be used in conjunction with base soil. First you place a layer of Super Soil at the bottom of each finishing container; then you layer a bed of base soil on top of the Super Soil concentrate; and then you transplant your fully rooted, established clones into the bed of base soil. As the plants grow, they’ll slowly push their roots through the base soil and into the Super Soil, drawing up all the nutrients they need for a full life cycle. The Super Soil can be also be used to top-dress plants that take longer to mature. I’ll use this mix for a full year.

Buds grown with this method finish with a fade and a smoother, fruitier flavor. The plants aren’t green at harvest time, but rather purple, red, orange, even black—plus the resin content is heavier, and the terpenes always seem more pungent. This method is now being used by medical growers all over the world, and with amazing results. The feedback I’ve received is really positive, including reports of hydro-like growth and novice growers producing buds of the same high quality as lifelong cultivators. So give it a try! You won’t be disappointed.

The Mix

Here are the amounts we’ve found will produce the best-tasting buds and strongest medicines:

• 8 large bags of a high-quality organic potting soil with coco fiber and mycorrhizae (i.e., your base soil)
• 25 to 50 lbs of organic worm castings
• 5 lbs steamed bone meal
• 5 lbs Bloom bat guano
• 5 lbs blood meal
• 3 lbs rock phosphate
• ¾ cup Epson salts
• ½ cup sweet lime (dolomite)
• ½ cup azomite (trace elements)
• 2 tbsp powdered humic acid

This is the same basic recipe I’ve been using for the past 15 years. The hardest ingredient to acquire are the worm castings (especially since many people don’t even know what they are. FYI: worm poop). But don’t decide to just skip them: Be resourceful. After all, worms comprise up to ¾ of the living organisms found underground, and they’re crucial to holding our planet together. Also, don’t waste money on a “soil conditioner” with worm castings; source out some local pure worm poop with no added mulch.