Can anyone tell me the optimal elemental ppm ranges for micronutrients for cannabis plants

Been mixing my own salts and I’m ready to start messing with micronutrients. Can anyone tell me optimal ranges and ratios for micros? Can’t seem to find much on the subject and the little I do find is all over the place. Any help is greatly appreciated. Have a great day everyone!

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I have this written in a google sheet that I got from below. Remember to subtract your tap water!

Common ranges in nutrient solutions for these elements are in parts per million: nitrogen 100-200, phosphorus 30-50, potassium 100-200, calcium 100-200, magnesium 30-70, sulfur 50, iron 2-12, manganese .5-2, zinc .05-.1, copper .01-.1, boron .2-.4, molybdenum .05, and chloride 5.

And also the thread here where I found that link

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Thanks man, much appreciated!

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I’d start with the numbers from plant prod’s chelated mix at 0.2g/gal and adjust from there.

That said, here’s what I personally view as optimal (ppm):

Iron 3.5
Boron 0.9
Manganese 0.8
Zinc 0.6
Copper 0.15
Molybdenum 0.075

If you are reservoir mixing, prefer iron in dpta form. Do not use cheaper sulfates for anything or you’ll mess up your iron.

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Hey brother, good to hear from you! That is exactly what I’m doing with the plant prod micros from custom hydro. My current targets are almost exact to yours, just want to tweak them a little.

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Also check this out:

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One possible set of ranges, micros on the right. Range from deficiency to luxury. Parenthesis value is Harley’s recommended not to exceed PPM under normal circumstances. Sulfur is the wildcard to help balance the ratios.

Another option is Jack’s M.O.S.T. The formulation is as such:

Might take a bit to figure out the masses to duplicate that.

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Thanks. I’ve been bouncing between Harleys recommendations and the ones suggested in the study done by the University of North Carolina. Settling somewhere in the middle. I have noted that Harleys recommendations for Zn, and Cu are much higher. Perhaps because the North Carolina study was done mostly on hemp varietals?

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What I believe Harley is suggesting via the parenthesis are the applied not to exceed values. They may not be ideal values for a particular crop. Sorry, wasn’t clear.

If UNC has a formulation for cannabis, probably lean that way. Or what Lefthand seeds has discovered in his research, just noticed his post above. He’s been working on that problem for awhile.

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He’ not mixi g solution from prepackaged nutes…he’s mixing each individual nute/micronute…like a gianormous chemistry set!

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I think you’re right. I was listening to the episode of perfect gardens on YouTube where Harley is discussing this particular chart. From what I remember the values in parentheses were his suggested maximums for those elements.

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I’m glad I commented. This is good stuff I probs will need chips for.

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hey id just like to shout you out for all your help and knowledge in these threads. i always find myself going over your posts every few months years in alot of situations and help back up my insecurities when i feel unsure of certain things. you bring a lot to this community and felt i would let you know that.

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That’s really kind of you to say. I really appreciate it. :pray:

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Here’s something from the University of Laval (introductory section in French, experiments in English):

37951.pdf (1.9 MB)

Be mindful of the results, the above attached appears to be thesis work and some of the experimental observations need verification. One example is the huge increase in Myrcene with the increase of nitrogen while some of the other parameters suffered. So happens Myrcene is considered one of the two most predominate terpenes across genotypes.

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@Northern_Loki. Excellent! Stellar information! This is the stuff I’m always searching for. I’ll have to go over it more in the morning, but this is something I can really use. Thanks for taking the time to post it all, very much appreciated!

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