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is this a cal, mag, zinc or some other deficiency

jackspratt61

Active member
Your soil pH is 5.4-5.7? That looks a lot like what I get for K deficiency.

If you water pH is high due to carbonates and you pH it down that should free the carbonate metals as long as your pH is low enough and you wait until all the bubbles are gone (12-24hrs) As long as CO2 is being relased the pH is changing.

If you are like me and have you soil overloaded from carbonates then there should little need for Ca and Mg as long as you nute pH is low and you don't keep adding more.

I've gone all rain and all well and 50/50 as far as water and still get the K def though a lot as my ignorance and the nutes I used. Still using a higher K nute and rain water with lower pH the problem persist unless I hammer it with KCl.

Mg shows up between the veins and is easily fixed. Ca shows up at the growing tips as yellow also easily fixed, K shows up at the margin and not easily fixed. That's my experience with high CO2 so it's exaggerated I guess.
What are you using for a P amendment?
 

Three Berries

Active member
Are you using dolemite?
I add some in the beginning and later in veg. Here's the current soil recipe with ProMix BX.

Soil mix per plant, 3 gal of ProMix Mx. 1 pt perlite. 2 qt worm casing. < for seed starting.

1 cup DS limestone. 3 Tbls 2K2MgSo4 <added for soil after transplant

5.5 oz of water to saturate 16oz cup of dry soil.

I didn't do much run off until three weeks into flower and found high pH. Two of the plants don't seem to mind at 7.1 or so but one does. It was way higher at 7.7 and now 6.8 but the damage is done.
 

jackspratt61

Active member
I add some in the beginning and later in veg. Here's the current soil recipe with ProMix BX.

Soil mix per plant, 3 gal of ProMix Mx. 1 pt perlite. 2 qt worm casing. < for seed starting.

1 cup DS limestone. 3 Tbls 2K2MgSo4 <added for soil after transplant

5.5 oz of water to saturate 16oz cup of dry soil.

I didn't do much run off until three weeks into flower and found high pH. Two of the plants don't seem to mind at 7.1 or so but one does. It was way higher at 7.7 and now 6.8 but the damage is done.
I was interested in promix until a friend got some of their organic mix that tested high in na. What was the starting ph for your promix?
You're mix is loaded up front with close to 2000ppm mg with those amendments not adjusting for cec. That's alot.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
here is today's pic... i do have a bottle of cal-mag from foxfarms, but will this lower the ph??? keeping in mind that my water is 7.5- i watered on wed and the soil is still moist today with a ph of 5.4-5.7 n yes i am growing under a mars fce8000.... thanks
My soil will show a pH of under 4 when it is growing and the microbes are happy. I call that 'sparking', and I think it is the ions exchanging and messing with the pH probe. When the soil has no root activity the pH is almost 8. The water I pH down to 6.3, and check / adjust that twice a day as it tends to go up.

I recommend pH the water to 6.3, make sure it is 70-75*F, add a little cal-mag and epsom salts. That is the reservoir. Take water from there and add microbes, enzymes, humic and fulvic acids, and top water the soil. Let nature have a chance, and quit with all the ferts and nutes. Make sure the air is circulating inside and being refreshed. Temps 75*F humidity 50%.

Things should do just fine.
 

blondie

Well-known member
Wood ash increases PH and gives nutes the plant can use. I’ve added a tablespoon of semi hardwood ash to my two gallon watering can at times and had no adverse reaction. Matter of fact, my ka5h seemed to like it. You really don’t need tons of nutes. Stopping for a while might be a good idea.
 

Three Berries

Active member
I was interested in promix until a friend got some of their organic mix that tested high in na. What was the starting ph for your promix?
You're mix is loaded up front with close to 2000ppm mg with those amendments not adjusting for cec. That's alot.
Not sure of the pH as in veg I never ran to run off. The BX runs out of nutes after about two weeks and is way short on any Ca. Only time I've had a Mg issue is when I just did two waterings with straight rainwater on my current grow. I get too much sulfur though in the past treating with the langbeinite and little success, I add a 1/4 tsp of epsom to a gallon of nutes.
 

jackspratt61

Active member
Not sure of the pH as in veg I never ran to run off. The BX runs out of nutes after about two weeks and is way short on any Ca. Only time I've had a Mg issue is when I just did two waterings with straight rainwater on my current grow. I get too much sulfur though in the past treating with the langbeinite and little success, I add a 1/4 tsp of epsom to a gallon of nutes.
all the mg is giving you trouble with k later on when the plant needs it. ca/mg about 10-12:1 in your media is good target. can't get there with dolemite.
 

zachrockbadenof

Well-known member
Veteran
My soil will show a pH of under 4 when it is growing and the microbes are happy. I call that 'sparking', and I think it is the ions exchanging and messing with the pH probe. When the soil has no root activity the pH is almost 8. The water I pH down to 6.3, and check / adjust that twice a day as it tends to go up.

I recommend pH the water to 6.3, make sure it is 70-75*F, add a little cal-mag and epsom salts. That is the reservoir. Take water from there and add microbes, enzymes, humic and fulvic acids, and top water the soil. Let nature have a chance, and quit with all the ferts and nutes. Make sure the air is circulating inside and being refreshed. Temps 75*F humidity 50%.

Things should do just fine.
i have foxfarms cal-mag, and i have epsom salts, as well as a bag of dolomite lime...

i am 'confused'
so my water out of the tap is 7.5... i left some water out for about18hrs, just checked it, and the temp shows 64F , n the ph went up to 7.9... as we say ... what the fuk...

so my water out of the tap is 7.5
when i mix the water n nutes, it drops to 4.4
when i add a teaspoon of baking soda (just a test, i won't use it on the plants) to 65oz of the nute mix, the ph is 7.5
when i check my soil, the ph is 5.4-5.6 depending on the plant, and thats after water only


so if i wanta get the ph somewhat over 6 , do i add some lime... epsom salt... cal-mag... or buy a bottle of ph up??

other then the bit of rust on a couple of the plants, all of em look good, buds r fattening up... its only 25day ,
 

jackspratt61

Active member
i have foxfarms cal-mag, and i have epsom salts, as well as a bag of dolomite lime...

i am 'confused'
so my water out of the tap is 7.5... i left some water out for about18hrs, just checked it, and the temp shows 64F , n the ph went up to 7.9... as we say ... what the fuk...

so my water out of the tap is 7.5
when i mix the water n nutes, it drops to 4.4
when i add a teaspoon of baking soda (just a test, i won't use it on the plants) to 65oz of the nute mix, the ph is 7.5
when i check my soil, the ph is 5.4-5.6 depending on the plant, and thats after water only


so if i wanta get the ph somewhat over 6 , do i add some lime... epsom salt... cal-mag... or buy a bottle of ph up??

other then the bit of rust on a couple of the plants, all of em look good, buds r fattening up... its only 25day ,

i have foxfarms cal-mag, and i have epsom salts, as well as a bag of dolomite lime...

i am 'confused'
so my water out of the tap is 7.5... i left some water out for about18hrs, just checked it, and the temp shows 64F , n the ph went up to 7.9... as we say ... what the fuk...

so my water out of the tap is 7.5
when i mix the water n nutes, it drops to 4.4
when i add a teaspoon of baking soda (just a test, i won't use it on the plants) to 65oz of the nute mix, the ph is 7.5
when i check my soil, the ph is 5.4-5.6 depending on the plant, and thats after water only


so if i wanta get the ph somewhat over 6 , do i add some lime... epsom salt... cal-mag... or buy a bottle of ph up??

other then the bit of rust on a couple of the plants, all of em look good, buds r fattening up... its only 25day ,
For now go with calmag since ph is low. K should begin being raised now too. I'd go with neutral ph to favor k,ca,mg uptake.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
I have two 100 gallon tubs of soil that I recycle. The soil in my current run may have had two bags of supplements, and maybe a bag of dolomite lime put in thinking it hadn't been replenished. The soil is unbalanced but the plants are getting used to it. When I started I was using oyster shell powder and ag lime to get the pH up.

I think of living soil as being like a supermarket, and the microbes are the shoppers. They take stuff off the shelves and give it to the cashier (roots) as the plant requires. Microbes are the key, and fungus too. You want organic goodness going on in the soil. Filter the chlorine out of your tap water and have a reservoir and bubbler to further air it out..

The pH in my water reservoir will increase as time goes by because I have a fish tank bubbler in there. Maybe CO2 is changing the pH, I dunno, but it goes from 6.3 to 6.7 overnight. I lower the pH with a little pH down, and later it will be up again. This is feed day. I will draw 2 gallons, mix up a batch of top-feed solution, and add 1/2 gallon flowering period goodness to the shelves of the soil supermarket. That is a once-a-week treat.
 

zachrockbadenof

Well-known member
Veteran
hey.... i watered the plants on tues very heavy, n they now again need water- i received a 2nd ph probe today, and it says 7.4 on the water , while the 1st one says 7.5- so they are close.. i will check the ec and now the runoff ph today...

i just added some foxfarm cal-mag 1/2 teaspoon to a 1/2 gallon of water, the the ph went down from 7.5 to 7.2, so no great drop- i will now water the plants n check the runoff and report back...
 

zachrockbadenof

Well-known member
Veteran
every plant got about 60/70oz of water with a 1/2 teaspoon of cal-mag

i am using '2' diff ph meters

ec ph in runoff ph in soil
headbanger 200-300 6.7-6.9 5.2-5.3
sd kush 200 6.5 4.7-5.0
purplepunch 2520 5.6-6.1 4.7-4.9
runtz 1550 5.6-6.1 5.1-5.3
sour diesel 420-560 6.1-6.5 4.7-5.1
bx3 700-840 6.3-6.5 5.3-5.5
tha melon 700 6.4-6.6 4.6-5.0

to me.... knowing very little, apparently the ec's on some are low, and a couple are way high. the ph in the runoff's look close ... i am not sure of what to make of the soil ph's...
comments??
 

linde

Well-known member
here is today's pic... i do have a bottle of cal-mag from foxfarms, but will this lower the ph??? keeping in mind that my water is 7.5- i watered on wed and the soil is still moist today with a ph of 5.4-5.7 n yes i am growing under a mars fce8000.... thanks
No don't use cal mag that will create more problems. Just flush with the tap water if you don't have regular pH up. Lime will work but probably take too long. Like I said earlier you have nutrient buildup in soil lowering the pH. Give them a heavy flush to remove excess nutrients. Buy some pH up to keep around
 

zachrockbadenof

Well-known member
Veteran
No don't use cal mag that will create more problems. Just flush with the tap water if you don't have regular pH up. Lime will work but probably take too long. Like I said earlier you have nutrient buildup in soil lowering the pH. Give them a heavy flush to remove excess nutrients. Buy some pH up to keep around
toooo late as i used a bit, but tomm i will flush the shit out of em... i just ordered a bottle of ph up.... thanks
 

linde

Well-known member
toooo late as i used a bit, but tomm i will flush the shit out of em... i just ordered a bottle of ph up.... thanks
I noticed that after I posted. Lol my bad ....ya that cal mag won't be absorbed when the pH is that low. It'll just build up in the soil like the nitrogen did. Then you'll be up a creek without a paddle. A good flush does wonders. I just ordered another quart of pH up myself. Your tap water is high enough pH it should correct the problem with a couple good flushes or atleast get the plants going in the right direction.
 

TanzanianMagic

Well-known member
Veteran
i have foxfarms cal-mag, and i have epsom salts, as well as a bag of dolomite lime...

i am 'confused'
so my water out of the tap is 7.5... i left some water out for about18hrs, just checked it, and the temp shows 64F , n the ph went up to 7.9... as we say ... what the fuk...

so my water out of the tap is 7.5
when i mix the water n nutes, it drops to 4.4
when i add a teaspoon of baking soda (just a test, i won't use it on the plants) to 65oz of the nute mix, the ph is 7.5
when i check my soil, the ph is 5.4-5.6 depending on the plant, and thats after water only


so if i wanta get the ph somewhat over 6 , do i add some lime... epsom salt... cal-mag... or buy a bottle of ph up??

other then the bit of rust on a couple of the plants, all of em look good, buds r fattening up... its only 25day ,
The water may not have a lot of buffering capacity, which is good after you get the medium's pH right. Actually that's probably not bad. I would just let the nutrients' pH adjust the water to 7.0 and not use pH down.

Lime is best mixed with the soil. So when you're potting up that's a solution.

The way to get the pH right is to mix 2 tablespoons of magnesium lime/Maerl per gallon of soil (2 tablespoons for soft water) into the new soil, soak it for at least a day and then transplant.

The pH to go for is 7.0, not just over 6. If you want the fast growth mobile nutrients N, P, K and Mg to be easily absorbed, you have to stay away from the low pH's.

Too high locks out micronutrients and some secondary nutrients which show in the growing tops. So if that starts to happen, you'll know it's too high. What is the right range also depends on which medium you use. In soil, it's 7.0.
 
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