Really need help choosing nutrients

Chunky Stool

Well-Known Member
20-20-20 has zero cal mag.
you don't need it in soil. you don't need to ph water, don't need to feed everytime you water, you only need patience... people will kill plants because they overcomplicate everything and think feeding soil is like feeding coco
So you are using a custom super soil???

Store-bought potting soil will not have enough calcium, magnesium or sulfur to flower cannabis plants -- period.

It *might* have enough micro nutrients, but probably not... :roll:
-- edit --
And it is definitely possible to have a ph problem in organic soil.
 

hotrodharley

Well-Known Member
you don't need it in soil. you don't need to ph water, don't need to feed everytime you water, you only need patience... people will kill plants because they overcomplicate everything and think feeding soil is like feeding coco
They did that before coco was ever a thought. Loving it to death. Newbie question “How soon can I start dosing them?”

A few weeks later - “Why are my leaves turning brown and crispy?”
 

Chunky Stool

Well-Known Member
They did that before coco was ever a thought. Loving it to death. Newbie question “How soon can I start dosing them?”

A few weeks later - “Why are my leaves turning brown and crispy?”
Cannabis is a big-time hog when it comes to calcium & magnesium.
There's no way you can buy a bag of soil and successfully flower cannabis using 20-20-20 only.

Sulfur is also essential for quality, and 20-20-20 has zero sulfur.

He is giving bad advice.
 

hotrodharley

Well-Known Member
Cannabis is a big-time hog when it comes to calcium & magnesium.
There's no way you can buy a bag of soil and successfully flower cannabis using 20-20-20 only.

Sulfur is also essential for quality, and 20-20-20 has zero sulfur.

He is giving bad advice.
Most nutes contain cal mag. Especially the 3-part systems. I use tap water, never pH and find most strains only require a dose of cal mag about week 4-5 of bloom. If I see a developing deficiency I address it. But excess calcium is a major cause of nutrient lockout.
 

Chunky Stool

Well-Known Member
Most nutes contain cal mag. Especially the 3-part systems. I use tap water, never pH and find most strains only require a dose of cal mag about week 4-5 of bloom. If I see a developing deficiency I address it. But excess calcium is a major cause of nutrient lockout.
Find a 20-20-20 nutrient with calcium, magnesium, and sulfur.
I'll wait...
 

steve870

Well-Known Member
Cannabis is a big-time hog when it comes to calcium & magnesium.
There's no way you can buy a bag of soil and successfully flower cannabis using 20-20-20 only.

Sulfur is also essential for quality, and 20-20-20 has zero sulfur.

He is giving bad advice.
check out my grow never used cal mag, outdoor too never used cal mag.

I think you should inform yourself before telling people i am giving bad advice. I wouldn't argue if i wasn't right.

Your probably the best grower though.
 

steve870

Well-Known Member
the only reason to use cal mag is because of coco coir. With its affinity for bivalent cations like ca 2+ and mg2+ . that's because it's CEC is close to 200 if not even higher.

Sulphur is normally available enough in the soil or in the atmosphere (not in hydro).
Magnesium deficiency is mostly only present in sandy soils prone to leaching.

Cannabis isn't a special plant and will grow like any other plants with proper care but i found that it likes to have a lower ec than most plants
 

Chunky Stool

Well-Known Member
check out my grow never used cal mag, outdoor too never used cal mag.

I think you should inform yourself before telling people i am giving bad advice. I wouldn't argue if i wasn't right.

Your probably the best grower though.
Dude, I've forgotten more about organic soil than you will ever know -- and I've got pics to prove it.

What brand of soil did you buy to use with your 20-20-20?
That is the topic, after all...
 

EndGreedMakeSeeds

Well-Known Member
For the money Mills hasn't let me down. 5litres of A+B for $100AUD and I'm on grow 7 or 8 now, about a litre left. Probably pumped out 30 plants that yield around 4oz each with the way I top, lst and scrog.

Never had to use calmag running Mills, but I've been adding 0.5ml per litre just incase for this grow. My first indoor grow I just used straight A+B because I had no idea wtf I was doing, the plants still turned out great - no deficiencies or nute burn.

Once I got more into growing in coco I started to use things like silica, PK 13/14, Bud Blood, Canna's Boost & Rhizotonic.

Start out with a cheap liquid pH test kit, maybe get some pH down, the town water in Aus is usually pretty high.
 

Chunky Stool

Well-Known Member
the only reason to use cal mag is because of coco coir. With its affinity for bivalent cations like ca 2+ and mg2+ . that's because it's CEC is close to 200 if not even higher.

Sulphur is normally available enough in the soil or in the atmosphere (not in hydro).
Magnesium deficiency is mostly only present in sandy soils prone to leaching.

Cannabis isn't a special plant and will grow like any other plants with proper care but i found that it likes to have a lower ec than most plants
Stay on topic.
This guy isn't using super soil. He's using store-bought bagged soil w/20-20-20 fertilizer only, which simply doesn't work for cannabis.
 

Chunky Stool

Well-Known Member
For the money Mills hasn't let me down. 5litres of A+B for $100AUD and I'm on grow 7 or 8 now, about a litre left. Probably pumped out 30 plants that yield around 4oz each with the way I top, lst and scrog.

Never had to use calmag running Mills, but I've been adding 0.5ml per litre just incase for this grow. My first indoor grow I just used straight A+B because I had no idea wtf I was doing, the plants still turned out great - no deficiencies or nute burn.

Once I got more into growing in coco I started to use things like silica, PK 13/14, Bud Blood, Canna's Boost & Rhizotonic.

Start out with a cheap liquid pH test kit, maybe get some pH down, the town water in Aus is usually pretty high.
Mills is a complete nutrient line -- unlike nutes listed as 20-20-20.
 

steve870

Well-Known Member
The reason many new growers have issues with soil is because soil already has nutrients and then they follow some crazy feed chart and overfeed their plants. Many also seem to think that anything that says "Bloom" is all they need in flower and think that if they add a whole bunch their plants will grow bigger buds. They end up with crispy fried leaves and nutrient antagonism and deficiencies that is hard to correct. Many also get caught up with checking soil runoff pH and if it isn't in the range they think it should be they dump high or low pH solution through their soil despite the fact that their plants are healthy. They try and fix something that isn't an issue because runoff pH is a terrible way to check soil pH as it's highly inaccurate.

If new growers using soil would just feed their plants modestly with a simple 2 - 3 part nutrient and skip all the additional additives many would find that they have no issues from seed to harvest. But in their defense it's hard to wade through all the crap marketing out there if you don't understand basic plant science. They get caught up in all these products with cool names claiming to increase yields by 20% with some proprietary blend of X, Y, and Z.
very true
 

steve870

Well-Known Member
Stay on topic.
This guy isn't using super soil. He's using store-bought bagged soil w/20-20-20 fertilizer only, which simply doesn't work for cannabis.
i wasn't using super soil either. Just what i could get on hand which is mg promix.

It's hard to stay on topic when people like you spread misinformation.
 

Chunky Stool

Well-Known Member
i wasn't using super soil either. Just what i could get on hand which is mg promix.

It's hard to stay on topic when people like you spread misinformation.
Unlike you, I have not said anything incorrect.

And given the fact that you use miracle gro soil with 20-20-20, maybe you should listen more than you talk.

You might actually learn how to grow...
 
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