Bookmarked. Good resource and post, friend. Thanks.
Stay up
Coffin_Dodger
Awesome! Saved
No problem yall. I found this randomly looking for copper deficiency ironically not listed here but im sure it was a ph issue on my part.
I used to have the cal mag def which i thought was heat stress from flowering in 80f.
I do semi organic and dont starve them (just top off a scoop at week 6) so i havent seen anything that bad in my last harvests just yellow or purping.
Grow journal in my profile so well find out
So I saw this article today when cruising the literature and thought this would be a nice addition for new growers. There are pictures for single nutrient deficiencies in plants and this experiment was conducted by a good group with good methods. Ive done this same thing with other plants in plant physiology and plant nutrition classes/labs.
The article is open access so free to read. Here is a screenshot of the article if the link doesn’t work. Just go to Google scholar and search the name and it should bring it up.
If anyone thinks this is more appropriate in a different category please feel free to move it. But I’d like to make sure all the new OGers got some good info at their disposal!!!
@moderators I wonder if there is value in pinning this to the top of the forum? The resources available here at OG are tremendous, but this could be useful!!
Edit to add: not sure why I threw the bud shot in…but please enjoy!! Its Notorious THC from humboldt seed
Good catch!
We all have been referencing the same coloured drawings for years now… It’s good to see the results of an academic study.
I’ve down loaded the PDF but what I really want are the photos (in high res), any ideas on how to get that?
(Edit)
Wow, has Hexo stock fallen in price… now sub dollar, I recall them hitting $500 a few years ago.
Cheers
G
I just plowed through the intro and Nitrogen def sections and was really impressed with the methodology and the well-written text. The online version has the pictures and they appear to be high rez/zoomable which is really useful.
@Gpaw is right, thanks for posting this @ThePotanist 
This study was a hydroponic run, using Dutch ? somebody’s nutrients.
Would this be the same for us, Organic fertilizers programs, with different mediums?
Killer good article IMHO.
Yeah! The nice thing about nutrient deficiencies is they look the same regardless of grow media. The reason for the hydroponics is because it lets you easily mix a balanced and controlled nutrient solution. It will also generally cause a quicker and more extreme reaction because soil material can easily contain enough micronutrients or other nutrients to make up for some deficiencies.
So the short answer after a long explanation is that hydro allows for more precise control over nutrient concentrations and elicits quicker responses but symptoms are the same. (That wasn’t really a short answer either, on me)
yup, hence for organic i use dr. earth. the ratio may not make sense when you read those ai written articles, but they made it to biodegrade without getting nasty and keeping a healthy smell if u dont over do it ph is fine with 500ppm 7.8 ph tap runoff is under 7.
for foliar synthetic is the way to go though some natural stuff works too (not fully organic like acetates “organic acids” etc).
Dr. Earth is a good fertilizer. I try to use a couple different sources of nutrition in the soil with the thought process that different blends break down differently. Using a mix of sources lets me make sure the plant has what it needs throughout its life.
Do you do a smell test? It should subside and smell sweet in my experience. People say you can’t over feed organic, you can. It robs oxygen and makes your pot into a compost bin hence ph problems and rotting leaves you see a lot with people pumping liquid organics into their grow on growdiaries.
Its the liquid fertilizers in my experience that cause problems like that. The liquid stuff is readily available for plants (and any other organism) to use. Not a bad thing if you have a good schedule and its your preferred style, but it can lead nutrient overloads and big pH swings if not done carefully.
I use solid fertilizers that leverage the microbes to make available to plants. It also provides different sources for microbes so I can keep a diverse population. Different substrates breakdown differently, can be consumed by different microbes, and will breakdown at different time points. So far I have never burned a plant or had pH swings (my pH is mostly self sustaining now, unless I add a real low or high pH solution, I have nothing to worry about).
The downside is I have to be planning when I add amendments. It takes about 10 days for amendments to become available to plants so I have to make sure I account for that time. I also have access to banging compost as I will be helping with our university’s compost program. That part is kind of unfair, sourcing good compost is hard. I just lucked into a great source.
Excellent study!!!
In summer I flower in low 90’s inside without much heat stress as long as there is fans. Thanks for posting always Wondered why my plant looks like death before ready to harvest lol. Can’t wait to read this article thanks!
My experience has been that growing indoors, especially under LED, turns plants into Mg hogs. I’m convinced this is due to cannabis tolerating insane light intensities, Mg is critical for photosynthesis and more light intensity means more chloroplast needed. If you supplement with only 1 thing, hands down for me it would be Epsom salt.
Good point!
I have seen it being chalked up to the spectrum, which made zero sense to me.
I’m partial to adding crushed Dolomite as a slow release Mg source but I keep some Epsom handy if I need fast release.
Cheers
G
Thanks for sharing this!! Anyone know of any studies on flower from different maturities/veg lengths? I’d love to see something that tells me I can flip early and not lose anything. Haha
@PatHealy you not gonna like what the literature says…
On a per plant yield. But consider a per unit area yield! It’s essentially a SOG where you expect small plants but lots of em, which compensates for small per plant yield. Bonus if you in soil and packing in a bunch for a short veg, you gonna do a lot of good for the health of the soil in terms of conditioning effects!
Crushed dolomite is a great amendment! The smartest strategy is honestly to use both and maybe even another slow release source. The more diversity you have in sources of nutrients the better protected you are from running low at a critical moment!