Do I Need to Use Supplements to Grow Great Weed?

Updated Jan 22, 2019

by Nebula Haze

Which Cannabis Supplements Are Actually Necessary?

“This is what puzzles me most, is all the nutrient companies have a “basic” nutrient line and then they have all the “extra” stuff they want you to give the plant to make big better buds. You can read in forums that growers think the extra stuff rocks and other say that it sucks. The companies all claim theirs is the best. I have not seen a study that shows bigger buds are more potent or even healthier. I wonder if it is like when you compare an organically grown apple to a non-organic apple. The Non-organic one is bigger and shiner but the taste and texture (the important things) do not compare to the organic one. Are all the “extra” really better or would the plant be happier without them?”

~ BuddMarsh

Oooh, this is a great question! So here’s the thing. You need base nutrients, and that’s it. You can get all the way to harvest with the most amazing and top-quality buds ever, with even the cheapest base nutrients and nothing else.

However, obviously, it’s more complicated than just that.

One thing I’ll say, and when you talk to growers who have tried a lot of different nutrient lines, you’ll often hear this…

Your environment and growing skill have a MUCH bigger effect on your final results than the specific nutrient system or supplements you use.

When I’ve tried different nutrients brands, I’ve had a really difficult time telling the difference. A lot of growers will tell you the same thing.

Mineral vs Organic Nutrients

The biggest difference I’ve noticed has been between nutrients that use mineral sources of nutrients vs organic sources. I feel like (in my experience) the mineral/chemical nutrients tend to get slightly faster vegetative growth and sometimes increased bud potency at harvest. Plants with organic nutrients grow slower in the vegetative stage and tend to produce buds with a stronger/more complex smell at harvest. But the difference is relatively small and you can definitely still get really smelly buds with mineral nutrients, and you can get really potent buds with organic nutrients!

These Supplements Work

Besides nutrients, there are some supplements that have a well-established use:

  • Root supplement – something that protects your roots like Hydroguard is really important if growing in hydroponics to prevent your roots from being attacked by root rot. But if your plants aren’t being attacked by root rot, it doesn’t really make much difference
  • CaliMagic supplement – if you’re growing in coco coir, or if using very soft water like reverse osmosis or distilled water, you’ll need to add extra CaliMagic to prevent Calcium and Magnesium deficiencies. However, if your plant doesn’t need CaliMagic, it won’t make much difference.
  • Silica supplement – Silica is often found abundantly in water, but if you don’t have a lot of silica in your water, your plant’s cell walls aren’t as strong. As a result, if your plant is low on silica, it has weaker stems and is more susceptible to heat stress. However, like the others, adding silica when you don’t need it doesn’t make a difference
  • PK Boosters & Shooting Powders – These add high levels of P & K. If you’re not giving your plants specially made flowering nutrients, they need another source of extra P and K. So for example if someone is growing in soil without adding nutrients, a PK booster is perfect for the flowering stage to make up for what the plant has used up in the soil.

So the main theme is that, when it comes to supplements, the ones that make the biggest difference have specific uses for the plant. If the plant doesn’t need it, adding a supplement can sometimes do nothing, or even worse it could hurt your plant. For example if you add a PK booster when you’re already giving full strength base flowering nutrients, you could burn or even kill your plants!

Then you’ve got supplements that don’t necessarily “fix” a problem, but “enhance.”

Which Supplements “Enhance” Buds or Growth?

  • Sugar and Carbohydrate based supplements – These claim to increase potency and trichome production, and appear to increase bulk. However, I’m not 100% certain they add anything but sugar to the bulk. The reason I say that is if a grower uses a lot of these types of supplements the plant can start oozing sugar sap. If you taste the sap, it’s sweet and not potent at all. I almost wonder if that extra “weight” is just sugar being stored in the buds and doesn’t necessarily add to the potency.
  • Other Enhancers – Then there are the more nebulous types of supplements which are meant to give overall improvements. For example supplements with Amino Acids, Vitamins and other non-essential plant compounds. These are a lot harder to measure the results. I’m sure some of them do what they say, while others are basically snake oil. It’s a lot harder to prove one way of the other with these, because it’s difficult to test unless you do a big side-by-side controlled experiment with a bunch of plants. And unfortunately, the industry just hasn’t quite reached that point yet!

When it comes to bud quality, it’s important to give the right nutrients so that your plant is healthy and vibrant, but other than that I think focusing on the environment (especially maintaining high light levels and proper temperature/humidity) have a much bigger effect on your final bud quality than your specific brand of nutrients or the specific supplements you use!

Cannabis buds after harvest drying upside down


Jump to…

Which Nutrients Work Best?

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