Yellowing leaves at 4 weeks into flowering - Super Skunk

Hi. I am really concerned about my super skunk leaves turning yellow. Plant is In soil. Using fox nutrients. 4 weeks into flowering. Light is 1000 watt led.
Should the leaves be turning yellow like this ?

Looks like cal mag deficiency. What are you using for water? Are you following the fox farms nute schedule and flush schedule? Ppm in and runoff? pH in and pH of runoff?
If it’s cal-mag you’re going to want to try and use something with zero or almost zero nitrogen.

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Thanks. I use tap water 6 ph. I don’t measure ph out or ppm in or runoff. How do i increase cal Mag if that’s the issue ? Maybe next time around I start measuring in and runoff

A You’ll want to pH your h2o when you water, pH your nute/water solution just before feeding then adjust, and then collect runoff after and pH that.

Ideally your pH should be around 6.5, but 6.2-6.8 is acceptable. If you’ve been watering at pH6.0 and adding nutes without checking the pH you may have a lockout condition. If you haven’t flushed according to their schedule and are using ff soil you may have a lock out condition. Plants need their growing medium to be with pH 6-7 in order to uptake the nutes. Go above or beyond it and they stop eating. This is what lockout is.

I’d water tomorrow, collect runoff and check the pH and ppm. After that you’ll know if you need to flush or just add cal mag.

Here’s the ff nute schedule. It’s imperative to flush when the recommend.

And a chart showing uptake of nutes at various pH levels

As you can see calcium isn’t accessible below about pH 6.2

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Thank you so much for the wealth of knowledge.

That’s why we’re all here. Welcome and feel free to ask questions.

Your plants are looking good, but you’ll want to keep an eye on them.


It seems that you have a Phosphorus Deficiency.
Here is a pic Look the same don’t they?


Benefit: Phosphorus does a lot of things for the plant. One of the most
important parts of Phosphorus is:
It aids in root growth and influences the vigor of the plant and is
one of the most important elements in flowering as well helps to germinate
Phosphorus is an essential plant nutrient, and since it is needed in large
amounts, it is classified as
a macronutrient. Phosphorus is a MAJOR important nutrient in the plants
reproductive stages. Without this
element the plants will have a lot of problems blooming without proper
levels of Phosphorus.

When your plants are deficient in phosphorus, this can overall reduce the size
of your plants. Not enough
causes slow growth and causes the plant to become weak, to little amount of
Phosphorus causes slow growths
in leaves that may or majhy not drop off. The edges all around the leaves or
half of the leaves can be
brownish and work its way inwards a bit causing the part of the leaves to curl
up in the air a bit. Fan leaves
will show dark greenish/purplish and yellowish tones along with a dullish blue
color to them. Sometimes the
stems can be red, along with red petioles that can happen when having a Phosphorus
deficiency. This isn’t a
sure sure sign of you having one though, but can be a sign. Some strains just show
the red petioles and stems
from its genes.
So pretty much the overall dark green color with a purple, red, or blue tint to the
fan leaves is a good sign
of a Phosphorus deficiency. Having Cold weather (below 50F/10C) can make phosphorous
absorption very troublesome
for plants.
Many people get a Pho-phorus deficiency confused with a fungus problem because the
ends of the leaves look like
a fungus problem, But the damage occurs at the end of the leaves. side of the
leaves and has a glass like
feeling to it as if it had a ph problem. Parts affected by a phosphorus deficiency
are: Older Leaves, Whole
plant, Petioles.

Too much Phosphorus levels affect plant growth by suppressing the uptake of: Iron, potassium and Zinc,
potentially causing deficiency symptoms of these nutrients to occur def in plants. A Zinc deficiency is
most common under excessive phosphorus conditions,
As well as causing other nutrients to have absorption troubles like zinc and copper. Phosphorus fluctuates
when concentrated and combined with calcium

Problems with Phosphorus being locked out by PH troubles
Cold wet soils, acid or very alkaline soils, compacted soil.


Phosphorus gets locked out of soil growing at ph levels of 4.0-5.5
Phosphorus is absorbed best in soil at a ph level of 6.0-7.5 (wouldn’t recommend
having a ph of over 7.0 in soil)

Anything out of the ranges listed will contribute to a Phosphorus deficiency.

Hydro and Soil less Mediums

Phosphorus gets locked out of Hydro and Soil less Mediums at ph levels of 6.0-8.5.
Phosphorus is absorbed best in Hydro and Soil less Mediums at ph levels
of 4.0- 5.8. (Wouldn’t recommend having
a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil
less mediums is 5.0 to 6.0. Anything
out of the ranges listed will contribute to a Phosphorus Deficiency.

Solution to fixing a Phosphorus deficiency
Some deficiency during flowering is normal, but too much shouldn’t be tolerated.
Any chemical or organic
fertilizers that have Phosphorus in them will fix a Phosphorus deficiency. If you
have a phosphorus
deficiency you should use any N-P-K ratio that is over 5.Again Peters all purpose
20-20-20 is a good mix.
Miracle grow Tomato plant food, Miracle grow All purpose plant food (Only mixing
at ½ strength when using
chemical nutrients, or it will cause nutrient burn!) Other forms of phosphorus
supplements are: Bone meal,
which is gradual absorption, I suggest making it into a tea for faster use, where
bone/blood meal is slow
acting, but when made into a tea it works quicker! Fruit eating bat guano, which
is fast absorption, Worm
castings, which is gradual absorption, Fish meal, which is medium absorption,
Soft Rock Phosphate, which
is medium absorption, Jamaican or Indonesian Guano, which is fast absorption.
Crabshell, which is slow
absorption. Tiger Bloom , which is fast absorption.

Here is a list of things to help fix a Phosphrus Deficiency.


Advanced nutrients Bloom (0-5-4)
Vita Bloom (0-7-5)
BC Bloom (1.1-4.4-7)
GH Flora Bloom (0-5-4)
GH Maxi Bloom (5-15-14)
GH Floranova Bloom (4-8-7)
Dyna-Gro Bloom (3-12-6)
Fox Farm Tiger Bloom (2-8-4)
Awsome Blossums


Dr. Hornby’s Iguana Juice Bloom (4-3-6)
Advanced Nutrients Mother Earth Bloom (.5-1.5-2)
Fox Farm Big Bloom (.01-.3-.7)
Earth Juice Bloom (0-3-1)
Pure Blend Bloom (2.5-2-5)
Pure Blend Pro Bloom (2.5-2-5)
Buddswell (0-7-0)
Sea Island Jamaican Bat Guano (1-10-0)
Indonesian Bat Guano (0-13-0)
Rainbow Mix Bloom (1-9-2)
Earth Juice Bloom (0-3-1)
BIO BLOOM (2-6-3.5)
AGE OLD BLOOM (5-10-5)

Any of these will cure your phosphorus deficiency. Affected leaves will not show recovery but new
growth will appear normal.

Now if you added to much chemical ferts and or organics,( which is hard to burn your plants when
using organics) You need to Flush the soil with plain water. You need to use 2 times as much water
as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use
10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

Note: Blood Meal, Dried Blood, Guanos, Kelp Meal, Cotton Seed Meal, Peat Moss,
Sulfur and fish meal are all acidic and can bring your ph down, so if you add these please monitor
your ph when using those.

Note: Bone Meal, Rock Phosphate, Wood Ashes pretty much all ashes, Shellfish Compost and Crab Meal are
all alkaline and can make your ph go up, so if you add any of these please monitor your ph.

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I’ll always defer to @garrigan62

It was these leaves, and the lack of “crispyness” that made me think a cal-mag deficiency.


And that 's what makes the world spin.
But Calcium Deficiency is more spotty kinda like these pic’s




These are all Calcium Deficiency’s

Of course the more I consume, the more things get fuzzy. I also thought potassium def.

He might have a lock out, which could compound issues. I guess I’ll wait to see what his runoff reveals.

Thank you, as always, for superior knowledge.

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Your very knowledgeable your self my friend and i’m fuzzy all the time…lmao