Phosphorus Deficiency Symptoms in Cannabis

Phosphorus is a mobile nutrient and is vital component of ATP (energy unit) of plants.
Phosphorus Deficiency What To Look For:
-Do not expect purple coloration that can be seen in corn and other plants.
-Often having the lowering leaves having a faint green color progressing to yellow that can also lead to browning.
-Tends to be subtle in mature plants, but since it is mobile look toward the older leaves.
How To Correct Phosphorus Deficiency:
-Often not needed
-Manures, Triple Super Phos and Bloom fertilizers all can add P for your plants.
Phosphorus Nutrient Warning
-Most growers over feed their plants Phosphorus
-There is a fear of not having enough
-The real issue by over feeding growers are wasting a resources that is becoming more limited.
Why Is There Not a Toxicity Image?
-Many growers are over adding phosphorus and not realizing it because there are no obvious visual cues of over feeding/toxic conditions.
-High levels can also vastly reduce the effectiveness of mycorrhizae if a grower makes this biological addition to the plants root zone.
Link to Lecture Slides: drive.google.com/file/d/1Ryec...
*Due to the description character limit the full work cited for "Phosphorus Deficiency Symptoms in Cannabis" can be viewed at... drive.google.com/file/d/1Zkht...

[@mahathiryusop]

Finally someone from the agricultural background, we need this in this industry!

[@DeBaccoUniversity]

An actual agriculture background is often hard to find in the cannabis industry, which is why DeBacco University is here to help fill in this knowledge gap.

[@woodskid4ever]

Search youtube for Dr. Bruce Bugbee. USU ag guru. Knows his stuff like this guy.

[@DeBaccoUniversity]

Another great resource, thanks for mentioning it.

[@archibaldmeatpants814]

I'm devouring all your videos...I'm so glad this showed up on my feed! Your work is amazing and MUCH appreciated!! Thank you!! Subscribed 😎👍

[@DeBaccoUniversity]

Thanks for commenting and subscribing! Encourage others to do the same!

[@tombryant4518]

Awesome video! Thank you for taking the time to make this available.

[@DeBaccoUniversity]

Thanks for taking the time to comment, glad to hear it was helpful. If you know of others that may also benefit feel free to share the video or channel with them.

[@tombryant4518]

@@DeBaccoUniversity I’ve been watching all your videos today. I’ve never had to deal with any nutrient deficiencies yet. Just had fungus gnats on my first crop. It is interesting to me how everyone seems to have different things happen to them.

[@rueporter2253]

Extremely thorough and accurate. Bravissimo!! Thanks .

[@DeBaccoUniversity]

Glad you liked the video and took the time to comment!

[@EnvironmentalCoffeehouse]

I'm so happy I found your channel. I'm just a small personal grower and I've never had yellow leaves on the outside before. So I'm learning learning learning.❤

[@DeBaccoUniversity]

Great to know the content is helpful be sure to share the channel with others!

[@kleptoko]

I’m a year into the industry and you good sir have advanced my knowledge greatly! Thank you

[@DeBaccoUniversity]

Thanks for sharing great to know the content has been helpful for you.

[@trippinaswespeak3628]

Thank you for all you do, extremely helpful, all your videos.

[@DeBaccoUniversity]

Great to know it is appreciated, but sure to share the channel and content with others!

[@dano9411]

Loving the library! Very interesting from a conservation perspective.

[@DeBaccoUniversity]

That is the intention to grow quality plants while not doing harm to the environment.

[@MrElemonator]

What a great video. Thank your Sir for sharing your knowledge.

[@DeBaccoUniversity]

Glad you liked it and thanks for the comment. Be sure to share it with others that you think may be interested.

[@cheddardavis5818]

I rarely see deficiencies but your vids help out a lot with identifying things !

[@DeBaccoUniversity]

Glad to help you even if indirectly.

[@GrowingTogether247]

I really appreciate your videos ❤ amazing information i have strated my first indoor grow, im doing ok , i normally would be doing it outside but trying indoor and loving your information...i have been adding videos on a weekly basis for my reference and to show others my experiences.. thanks for the awesome content

[@DeBaccoUniversity]

Thanks for the comment! Please share the channel with others!

[@GrowingTogether247]

@@DeBaccoUniversity Thank you.. hoping for good results but I set my expectations being my first indoor.. learned the most from your channel and a few others... take care and keep up the great content.. 👍

[@Gabachazo]

A very large plant for such a tiny pot, surprisingly healthy plant for such minimal root volume...

[@DeBaccoUniversity]

This is in part possible to to the continual (daily) liquid feed of nutrients, which also fits well when trying to create deficiency symptoms.

[@superkillr]

@@DeBaccoUniversity They shoulda done a much better job than... hey a leaf is different. WOOOPTy DOOOOO.... come on, they really came out after all that and the money spent to have a show a plant that is like 2 inches shorter and a yellow leaf on the very bottom. WTF?

[@JM-ym8mm]

@@superkillr just goes to show how little signs there is for phosphor deficiency. Don't shoot the messenger ;p

[@craftgrow]

Thanks for your time and info

[@DeBaccoUniversity]

Glad to help, watch the phosphorus additions... the bass with thank you.

[@jaygrice2682]

Love these videos!!!!!

[@DeBaccoUniversity]

Love these comments!!!!!

[@AussyCC]

Source and sink cells are prominent in your deficiency pic mate. Right has BRIGHT green leaves (phos def) with nutes being sinked from your clorating source leaves, left is control. Thx for the upload.

[@DeBaccoUniversity]

This DeBacco University video may help add more science to what you have mentioned... kzbin.info/www/bejne/eZ7IhX6ZrNajrpo

[@everennui1]

Thank you again and again and again for all the concise information about all these things. I would like to grow as environmentally conscious as possible, considering hydroponics and RO water already has an impact, but I am very new to gardening and the amount that I don't know is increasingly becoming more apparent. It's very daunting. Can you point me in a direction so that I can learn about synthetic nutrients better? I understand there's different types of NPK and some of those interact better with different styles and watering strategies. I'm particularly interested in deep water culture and drain to waste using coco coir as a medium. I'm also interested in NFT for strawberries and lettuce. I'm not interested in nutrients that require bacterial life to break it down, I would much rather use plant available salts and ideally stack a lower EC input in the substrate so that I don't have to get as much runoff. I would say, "any help would be greatly appreciated", but you already have helped me out so much in the past. Anyway, thanks again, because you have a masterclass of information already available here.

[@smoothmove7566]

Okay now I see what you were getting at, I did not know that phosphorus was a dwindling natural resource. I just figured we could make all we ever need. Why can't everybody be mellow and smart like you?

[@DeBaccoUniversity]

Thanks for the "mellow and smart" compliment not a common one, but a good one regardless!

[@fitness3447]

Thanks for this video. Highly helpful.

[@DeBaccoUniversity]

Glad to hear it was helpful and thanks for taking the time to comment.

[@Rick-lx5oy]

Very helpful

[@DeBaccoUniversity]

Glad to hear that.

[@SaltyFarm]

If you’re growing in living soil, use seabird guano to treat a deficiency and mineralized phosphate early for your feeding program. If you reuse your soil with rock phosphate, you’ll have less deficiencies late in flower. I sometimes notice a little blue in my leaves after a major growth spurt if I’m not on top of it, especially if I’m experimenting with new products and find one that really does well.

[@DeBaccoUniversity]

Not a common deficiency seen, but good to be aware of.

[@wildsidebryan]

fta. i enjoy your content. The scale difference in the y-axis for the plots at 5:35 is a bit deceiving for showing the magnitude of the problem.

[@DeBaccoUniversity]

Both show Millions of Metric Tons.

[@E_-_-]

Nice. Another study showed that P deficient plants produced same dry weight and P is 'front loaded' early in the cycle (i.e. P application is not needed later in the grow). Might've been the same study. too long ago

[@E_-_-]

Using phosphoric acid you aklmost reach P target if your base was X-0-X haha. Overfeeding P, What is target P ppm is missing in this video. Tomato, cucumber, pepper are high dli plants grown at 200-350 ppm K just like the green plant. ~40-70 ppm P is target there

[@DeBaccoUniversity]

In field applications optimum is considered to be around 30 pounds to the acre.

[@superkillr]

@@DeBaccoUniversity How does that serve the people watching this video... do you think people are growing weed by the acre?

[@donwheeler1208]

Although I’m sure you’re correct that people do over feed, I think that this quickly growing industry plays a large part of demand. And don’t forget the more place’s it’s legalized, the more home growing follows.

[@DeBaccoUniversity]

This is the importance of educating new and seasoned growers.

[@michaelallen6208]

Do you have a potassium video? Need asap please

[@DeBaccoUniversity]

While this study was done on tomatoes, it would look very similar in cannabis, hope it helps... kzbin.info/www/bejne/j5zOmoSrnMadgtk

[@brendanbeaudoin6573]

Thank you for the informative breakdown on Phosphorus! I am experiencing what I believe to be P lockout due to high levels of Calcium in my tap water. I'm seeing purple/red stems/petioles, slow growth, and yellowing and browning of the leaves as you've mentioned. This is an organic soil grow with PH around 6.5 during watering with very light feeding in between with BioBizz nutes. My plants only show these symptoms in an indoor environment, but never outdoors. How would you recommend mitigating this potential Phosphorus issue? I'm contemplating using and flushing with RO water to reset things, but on the other hand thinking of just adding a bit more Phosphorus to balance the CA and P ratios.

[@DeBaccoUniversity]

Based on your description it sounds like more than a Phosphorus issue. If you are seeing it only indoors and not outdoors what is the substrate the plants are growing in and/or what is the lighting for the plants? The coloration on the stems is more likely due to other (not nutrient) stresses on the plant.

[@seriusb9122]

@@DeBaccoUniversity Thank you for the response! Growing indoors with straight Fox Farms OF. Spider farmer 4000 LED. 78 temp, 68 humidity in 7 gallon smart pots. I go 1/4 strength feedings with Biobizz, so very light feeding. I’ve always struggled with the red/purple stems indoors and other than having wry hard water, I cannot figure this out. Thank you

[@DeBaccoUniversity]

@@seriusb9122 What is the pH of the water/nutrient solution? What pruning method?

[@eugenecorcoran5478]

Starving for calcium ....because ph is too high for uptake in hydro. I take water before the water softener process.

[@superkillr]

@@eugenecorcoran5478 It's not hydro... read

[@timpage5021]

What size containers you're useing and how often did you water and feed? Did you water everyday?

[@DeBaccoUniversity]

In the trial 5-gallon containers were used with watering typically twice a day. The frequency and amount is based on plant stage and environmental conditions (sunny vs cloudy day) and also media used can impact the plants required water. Feeding was continuous for six days with the seventh being a flush day to remove excessive salts. Typical target for standard feeding was 100ppm of nitrogen. Hope this helps.

[@timpage5021]

@@DeBaccoUniversity yes it did thanks. I figured you was watering at a minimum of 1 time a day for plants that size. Again thank you. Stay safe.

[@eugenecorcoran5478]

Drink when thirsty ......and water your plant when dry to get that oxygen and nutes in there.......not every day....less pot is undersize I guess.......and 72 hours between watering s is sign of proper size pot.

[@rickrolls3786]

All meat, no potatoes...love it!

[@DeBaccoUniversity]

That is the goal here on DeBacco University.

[@BangBangBang.]

A lot of the phosphorus in the Southeast comes in via ship from Peru.

[@DeBaccoUniversity]

Imports of Phosphorus seem to be on the rise.

[@sensimilla8884]

The first pot looks far too small for the plant is it not suffering from root lock as well?

[@DeBaccoUniversity]

Rockwool blocks can produce large plants with a small root area, so while there may be some root stress going on this is counter acted by the irrigation events (twice daily) provided to the plants.

[@paulg3012]

What is the cause of red/purple leaf petioles and upper main stalks?

[@DeBaccoUniversity]

Often times this can be a plant response to environmental stresses. Ex. Strong UV light exposure.

[@paulg3012]

@@DeBaccoUniversity Thanks.

[@germanhd1211]

What are all those white spots on the upper leaf at 3:40?

[@DeBaccoUniversity]

The white spots are actually some thrip damage.

[@paulg3012]

@@DeBaccoUniversity Spinosad destroys those little buggers.

[@andrewbee82]

I was told that Pdef shows also with a dark green/blue green coloration of the leaves. Seems to be not the case 🤷🏻‍♂️

[@DeBaccoUniversity]

In this presentation you are seeing the results of a cannabis plant grown in a controlled greenhouse that was fed restricted (below optimum) levels of phosphorus.

[@andrewbee82]

@@DeBaccoUniversity I’m not retarded, no need to repeat the basics, I’ve watched the video and understood it. I was ASKIN if those I mentioned are pdef symptoms too...are them? Thx

[@DeBaccoUniversity]

No.

[@andrewbee82]

@@DeBaccoUniversity thank you and sorry to have been lil rude. 👋🏻

[@gipen]

How can you grow that big plants in such small containers. My plants get stunt if I don't transplant them.

[@DeBaccoUniversity]

Daily attention;-)

[@andrewwilloughby2370]

My plant is showing this at only week 3 into flower is it normal to yellow that early on?

[@DeBaccoUniversity]

Sign of stress.

[@johnslugger]

*I use a mixture of 50% Mono-Sodium Phosphate and 50% Di-Sodium Phosphate for a pH neutral Phosphate additive.

[@DeBaccoUniversity]

At what rate? That is highly concentrated.

[@johnslugger]

@@DeBaccoUniversity 50/50 mix added at 850 PPM.

[@nathanbrown8409]

How do I fix this issue if I where to have this issue?

[@DeBaccoUniversity]

Step one is the realization and then stop adding phosphorus.

[@Allknowingkeith]

Anything new to learn about phosphorus?

[@DeBaccoUniversity]

Do not over add it.

[@Greek5425]

Btw,using bloom boosters is a complete waste of money.Loading up on phosphorus during flowering does not increase floral structure.Cannabis uses the majority of phosphorus during the first few weeks after the seedling stage.

[@DeBaccoUniversity]

Always nice to see other educated growers;-)

[@overthenever4262]

Dear God , those plants where how old ?!?!? Holy omg frikin lord of Shiva Batman !!! I'm just sayin , don't jump on me ......... "But" , and I really love this channel it's just that ,. Well.. WoW , my plants are 78 days and ,.

[@DeBaccoUniversity]

Plants pictured were about 80 days old to allow for the deficiencies to be easier to see.

[@1HeavyHitr]

These videos are awesome and very informative but damn dude take a drink and kill those pasties!

[@DeBaccoUniversity]

Glad to hear you like the information.

[@user-oh3gr8zh1c]

Hi dr debacoo, I wan't to know if you've a contact e-mail to ask you a couple of questions that I've regards

[@DeBaccoUniversity]

Post your email and DeBacco University will reach out to you.

[@ismahappyfacedot]

Be picky with your budbro

[@DeBaccoUniversity]

Goal is to be selective.

[@daineball]

yeah purple can be from bending stress and genes

[@DeBaccoUniversity]

You are correct.

[@greenteam5627]

Bending stress?

[@daineball]

@@greenteam5627 Low/High Stress training and if outdoors high "cooler" winds will turn stalks and stems purple from stress, which i refer to as bending stress not environmental or light related which all can also do the same sorta thing but they all look slightly different

[@donnyinalaska]

So... being I'm in my upper 50's, why is it todays Cannabis is nothing near what it use to be as far as strengths , compared to what we had back in the early 90's down to the 60's ? Seems most of the stuff that is sold in stores these days all smell the same, even tho there are different names on the packages ? I mean stuff we bought back in the 80's was majorly superior compared to todays stuff.... Back in the day, 3 to 6 hits was all you needed... Is it all the chemicals they grow it with today that has degraded Cannabis ?... cause it aint the same, thats for sure....

[@DeBaccoUniversity]

Depends on the strain you are using. There are some very potent cannabis that exists today, the key is to be sure you have supporting documentation with the product you are using from an independent lab to verify what is claimed.

[@greenteam5627]

You definitely don’t live on the west coast. Cannabis from any state on the west coast would have your head spinning on your shoulders after 3 hits.

[@donnyinalaska]

@@greenteam5627 , wanna make a bet that I dont live on the west coast ? Seattle mean anything ?...hahahaha Besides, the stuff we got back in the 70's and 80's didnt need chemicals to make it grow... It was far superior compared to todays stuff...lol

[@greenteam5627]

@@donnyinalaska Wel, idk what circles you’re in or what you’ve been smoking man but if you live in Seattle, stop by The Reef on Cap Hill and smoke anything from Skord or High Tide. You’re literally the first and only person I’ve heard say cannabis has gotten weaker 😂 Okay man.

[@donnyinalaska]

@@greenteam5627 , well.. at almost 60 years old, things change..lol

[@guyfawkes8790]

Algorithm bump

[@DeBaccoUniversity]

Thanks for the bump, hope it helps some people.