So I have a cheese hybrid plant that is showing a magnesium deficiency. It started with yellowing veins. I foliar fed the plant with 1tsp per gallon of epsom salt. I thought it was getting better because I didn't see any signs on the newer growth but now some of the veins are turning brown so I think it's getting worse. I had another strain in the same soil that was showing the same problem and I foliar fed that one and the problem stopped no browning on the veins looks good now. I think my soil is deficient in magnesium. I use Spartans agricultural lime because that's what my local hydro store offered it's 30% calcium and 3% magnesium. My question is should I start watering with 1/2 teaspoon of epsom every water now to supplement the low magnesium in the soil?
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Agricultural lime and epsom salt
- Thread starter bigjdawg
- Start date
mg deficiency responds well to foliar spraying. make sure you disolve the mg in a couple tbl spoons of warm water to get the mg to disolve better. use a drop of dishsoap in the sprayer to allow a thorough leaf coating. good luck. if its a mag deficiency, you'll notice the improvement in a couple days. because calcium and iron can sometimes look the same as mg deficiency, you may want to foliar with botanicare's cal-mag w/ iron. good luck
As always pics will help a great deal. May also be wise to post this in the infirmary.
How much lime did you mix into the soil or did you top dress? Brown veins doesn't ring a bell for me regarding magnesium deficiency but maybe I have never seen it that severe!
How much lime did you mix into the soil or did you top dress? Brown veins doesn't ring a bell for me regarding magnesium deficiency but maybe I have never seen it that severe!
I used 1 cup per cf mixed into the soil. Probably won't be able to post pictures till later tonight. It's like brown spots on the veins. I had two different strains showing the same starting problem of light green/yellowing veins. The kush I foliar sprayed doesn't look any worse new growth looks good. The cheese plant I sprayed to and it didn't improve its slowly getting worse on the leaves that were already affected.
No I'm using lc's soiless mix
5 parts peat
3 parts perlite
2 parts worm castings
1 cup agricultural lime
I'm using it with the guano tea
1/3 high n guano.... I'm using sunleaves sumatran 8-3-1
1/3 cup seabird guano 12-11-2
1/3 cup worm castings
1tsp maxicrop 1-0-4 per gallon
1tsp of molasses per gallon
All ingredients added to 5 gallons of water and brewed with air pump for 24hrs. I have used the tea twice one time in Veg and 4 days ago when I switched to flower. I sprayed 1 tspn epsom when I first saw the problem and then a few days later sprayed with plain water maybe I should give it time but like I said my kush plant stopped progression on the leaves and looks the same as when the problem started. The leaves on the cheese look like their getting worse on the affected leaves.
5 parts peat
3 parts perlite
2 parts worm castings
1 cup agricultural lime
I'm using it with the guano tea
1/3 high n guano.... I'm using sunleaves sumatran 8-3-1
1/3 cup seabird guano 12-11-2
1/3 cup worm castings
1tsp maxicrop 1-0-4 per gallon
1tsp of molasses per gallon
All ingredients added to 5 gallons of water and brewed with air pump for 24hrs. I have used the tea twice one time in Veg and 4 days ago when I switched to flower. I sprayed 1 tspn epsom when I first saw the problem and then a few days later sprayed with plain water maybe I should give it time but like I said my kush plant stopped progression on the leaves and looks the same as when the problem started. The leaves on the cheese look like their getting worse on the affected leaves.
biggreg
Member
Peat has a variable lime requirement. A standard recipie will not produce a standard soil.
Usually 3 to 4 grams of lime per liter but can go up 15 for really broken down muck.
The castings are another variable product. No recipie works every time.
A ph meter and some distilled water will tell you
Usually 3 to 4 grams of lime per liter but can go up 15 for really broken down muck.
The castings are another variable product. No recipie works every time.
A ph meter and some distilled water will tell you
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It sounds like the one plant (cheese) may be suffering from a calcium lockout.
If you're using tap water as your water source it could be loaded with calcium bicarbonate which would begin to lock out a bunch of other elements within your soil mix because it will cause your soil pH to rise above ideal levels.
The other plant, indeed, sound as if it's suffering a Mg deficiency.
If you're using tap water as your water source it could be loaded with calcium bicarbonate which would begin to lock out a bunch of other elements within your soil mix because it will cause your soil pH to rise above ideal levels.
The other plant, indeed, sound as if it's suffering a Mg deficiency.
That is not yellowing veins. That is intervein yellowing > for future reference.
Yes, castings can be very variable. Unfortunately there are some organically certified castings (from African and European big worms) which have been restricted to a diet of certified organic peat and wheat which have in my experience and a couple of growing associates experience come with a fungal pathogen, resulting in leaf spot (rust).
The certifiers should loosen this so worms get a variable diet.
Here is what the cheese looks like. I think it's just a bad magnesium problem and I think I let it get worse because I sprayed with epsom salt and thought one spray would be enough and didn't see the deficiency move to new growth so I thought it was fixed but then the leaves that were affected started looking like this
Attachments
I don't think it would be calcium lockout because I've used the same soil mix and water for the last year. The only thing I changed was i went from the blood bone and kelp recipe to the guano tea recipe. I just think the agricultural lime is lacking on magnesium because it's 30% calcium and 3% magnesium. I know dolomite lime is 22% calcium and 11% magnesium but I couldn't find pulverized dolomite lime anywhere. The grow store said the agricultural lime should be fine
That does look like magnesium deficiency! Especially if it starts low down.
If you were going to bake a cake and couldn't find baking powder but someone told you baking soda should be fine...
When a plant is lacking magnesium the fan leaves point up like they are "praying for magnesium". A teaspoon of Epsom salts and water poured into the soil would show an improvement in a few days if there was a magnesium deficiency.
I think you have something else going on.
Sativas are finicky eaters in my experience and difficult to grow. I hope you have some mothers growing and are taking careful notes.
Burn1
i would have to agree with the calcium statement. Looks like you had an initial surge of P then mg got locked out along the way. mg is required for proper uptake of P. Is your soil crusty? if so a good liquid calcium, i use age old brand, usually does the trick and keeps things productive.
