Super Soil Compost

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Grow Gear


Our ‘SuperSoil’ Compost Mix is a modified version of the popular SubCool recipe. It is ideal for lining the bottom half (½) of the pot, and using regular potting mix for the remaining volume of the pot. The idea behind 'SuperSoil' is that in mimicking the richness and diversity of a well-established rhizosphere you should never have to adjust the pH or deal with nutrient imbalances.

'SuperSoil' has been made to provide more than enough nutrients for your crop, so that it can be grown entirely with (tap) water. Through the use of nutrient dense amendments like Guano, Blood 'n' Bone and Dolomite, we are able to provide enough nutrients for your plants needs in just the bottom half of the pot!

Note: 'SuperSoil' is a type of ‘Hot’ compost, meaning that you should never allow a plant’s roots to be touching 'SuperSoil' when transplanting.

Sold per bag, at approx. 25 litres per bag.

What You'll Need To Finish The Recipe:

To complete the recipe, cut the 25L of 'SuperSoil' Compost Mix with 25L of Peat Moss or Coco Coir and 20L of Aeration ingredient (Pumice/Scoria/Rice Hulls/Perlite) resulting in approximately 70L of final 'SuperSoil' Mix from a single bag of our compost!


Oyster Shell Flour - Freshly ground oyster shells are composed of approximately 96% Calcium Carbonate, with the remainder being trace elements, kelp and microbes. Oyster shell flour not only releases calcium and trace element, but is also a liming agent, improves tilth, provides favourable conditions for microbial activity, stimulating enzyme activity and increasing Cationic Exchange Capacity (CEC).

Oyster shell flour is a very special component of our compost blends because the slow release calcium helps to increase the structural integrity of plants, promote new growth and increase resistance to disease by facilitating the movement of heavy macro-molecules around the plant.

Oyster Shell also contains Chitin which is beneficial to the plants immune system when converted into chitosan by an enzyme released from the plant (chitanase).


When used as a soil amendment Bokashi invites a galaxy of beneficial bacteria and fungi that result in increased yields and healthier plants via probiotic effects in the soil. In addition, they hasten the breakdown of amendments and transport them to the plant as part of a symbiotic relationship, and help to ward off nematodes and other invaders, among many other benefits.

BioChar - BioChar is a special type of agricultural charcoal that is high in carbon content. The mechanisms of action are not fully understood, however it is suspected that it works by increasing the amount of sequestered carbon available to the plant. BioChar assists in purifying toxic heavy metals in the water/soil, providing both water retention and aeration, as well as an environment for microbes to inoculate. For this reason, you'll see greater benefits from BioChar over time, making it an ideal amendment for NoTill conditions.

By using sustainably grown Australian hardwood the BioChar in our mixes routinely tests at 89 to 93% carbon, compared to cotton gin waste or sugarcane bagasse which can be as low as 10% (10% carbon is still allowed to be called BioChar by international standards). It is sourced from plantation waste, so in using our premium compost mixes you are ultimately sequestering carbon back into the soil once used. 

Malted Barley Grain - Malted Barley Grains are an exceptionally rich source of microbes, with a wide range of bacteria, filamentous fungi and yeasts colonising the area between the husk and the pericarp which produce biologically significant levels of indole-3-acetic acid (IAA), a hormone that promotes cell division and is essential for the proper development of plant organs. The grain functions in the mix as a source of growth hormone catalysts, facilitating explosive growth.

Kelp Meal - Kelp Meal is mild source of Nitrogen and Phosphorus and Potassium (1-0.5-3), and is a source of trace minerals, amino acids, plant micro-nutrients and natural plant hormones. These hormones are specifically noted to reduce stress associated with transplant and heat shock, which in turn will allow your plants to grow quicker and transition more smoothly after transplants.

Neem Cake - Neem Cake provides a fantastic source of NPK with values of 4-2-2 respectively. Furthermore there are several molecules in neem cake such as Azadirachtin, Salannin and Nimbin which  provide integrated pest management to your garden, acting as an antifeedant for over 200 species of insects. 

Epsom Salt - Epsom Salt provides the 'SuperSoil' with Magnesium, which is necessary for Calcium uptake; as well as Sulphur which is not only the most important element for flavour, but also plays a vital role in nitrogen fixation (is present in the important nitrogenase enzymes which contain a Fe-Mo-S cluster) and is used as a catalyst. Sulphur is also involved in proper function of the immune system of plants via having ample glutathione to combat oxidation stress. 

Dolomite Lime - Dolomite acts to counter the soil pH dropping (caused by microbes) and thus can be thought of as a pH buffer. It also provides another source of both Ca and Mg. 

Azomite -  Azomite is a trace element source, conditioning agent and also helps plants better absorb nutrients from soil. The rare earth elements present in Azomite enhance nitrogen fixation by Azotobacter species, which bind atmospheric nitrogen and release it as ammonium ions into the soil. Further, the Azomite present in our Super Soil acts to reduce stress caused by drought by enhancing Abscisic acid (ABA) production, in turn minimizing the water lost by a plant in transpiration.

Blood 'n' Bone Meal - Blood 'n' Bone Meal is high in Calcium, Nitrogen, Phosphorus (8-5-1). It improves soil microbial activity and promotes worm growth and development by providing available organic material. The rich Nitrogen content gives plant the building blocks they need to handle intense growth during both the vegetative and bloom phases. 

Humic and Fulvic Acids - Humic and Fulvic acids are organic polymers which coordinate and chelate with macro-molecules/metals, and assist in facilitating uptake. They also act to neutralise soil pH, allowing trace elements to become available to the plant. Through the use of Humic and Fulvic acids you will notice increased gains in plant growth, their general appearance and the flavour and size of the harvest.

Guano - We utilize a special sulfur and silica rich Guano which acts to strengthen the plants stems, stimulate soil microbes, improve soil structure as well as providing a powerful phosphorus source to allow maximum fruit development. Through the use of the extra sulfur we have found flavours are simply unbelievable!


Returns Policy

You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the 'Complete Orders' link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.


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