There are numerous cannabis nutrient supplements on the market and most make fantastical claims. Some growers seem to be convinced that they need it all and spend hundreds of dollars on expensive supplements. Other growers, seem to believe that it is all hype and the plants will do just as well with nothing but the base nutrients. As with most similar issues, the truth is in the middle. There are a lot of products that make claims that are hard to believe. However, there are also some products that will yield significant benefits to your cannabis plants grown in coco.

This article reviews the supplements that we actually use and the reasons that we use them. As you consider your own supplements and nutrients, we have several resources that you should consider.

• To begin, read our articles: “Principles of Fertigation”, “Understanding Osmosis and EC", and “Cannabis Fertilizers, Supplements, and pH"
• You may also want to consider our tutorials, “How to Mix Nutrient Solutions”, and “How to Set EC Targets”

Best Nutrient Supplement Practices

Consider EC:

When considering supplements, you should always be aware of your EC targets for your nutrient solution and the EC impact that the supplement will make. See our article, “Cannabis Fertilizers, supplements, and pH” to learn more.

Keep It in the Family:

Whenever possible use supplements from the same nutrient supplier. When you mix nutrients from different suppliers it can throw off the NER and potentially create lockout. This is particularly true for Bloom Boosters, but is not a problem for supplements like surfactants, humic acid, or silicon.

Our Recommendations

These are the specific nutrient supplement products that we recommend for the best results when growing cannabis in coco coir.

Cal/Mag Supplement

In addition to the supplements listed below, you NEED to use Cal/Mag supplement in coco! Be sure to read our article "Why You Need Cal/Mag in Coco"

Surfactant (Wetting Agent)

Wetting agents reduce the surface tension of the water. This essentially makes the water wetter and promotes distribution of water. In coco, wetting agents promote the lateral movement of water in the media and ensure that the full volume of the media is properly saturated. This is useful when hand-watering and essential when using an automatic watering system.

SM-90 is my preferred wetting agent, however it is currently unavailable. In its place, I recommend using RAW Yucca Powder. Yucca is an excellent wetting agent and there is evidence that it brings other benefits to the plant such as improved ability to handle climate changes and pathogen resistance.

Doses are very small! I use 1/8 tsp per 5 gallons. I recommend measuring 1/8 tsp and dividing it into 5 piles. Once you get this sense of how much you need you can just eyeball a pinch. The dose doesn't have to be super precise, but it should be reasonably close.