Dialing In MEGA CROP for Auto's

[pop22]

There is very little nutrient in most organic potting soils unless your using something like Fox Farms, etc that is loaded with organic nutrients. I've never had an issue. Note also that I use recycled soil from my pots. I don't flush either, yet I've been using the same soil for years.

Thanks Pop22! the ability to hold onto nutrients isn't something I considered. I'll up it to 600 for a week and see what happens.

With regards to the soil you're using. Were/are you not concerned with the soil already having enough nutrients that adding MC from the start is pushing the plants too hard in the beginning, at least during veg?

 

[pop22]

I dispute this feeding schedule thing. Having grown in auto pots for a few years then back to regular pots, I've found no evidence or need to feed on a schedule. I feed every watering without issue. it make a big difference when your not over feeding to begin with. I feed at the same ppm from start to flower. I don't give water between feedings for this reason and after almost 4 years of using MC, I have found no justification for using a feeding schedule. I feel feeding schedules introduce more problems than they cure, and are really nothing more than make work IMO. I The only change I make is upping the ppms in flower.
I will concede that you may be on to something with the sulfur, however, is it a deficiency or lock out? very little sulfur is needed by plants.

You need to be flexible a bit with your fertigation schedule in soil and pe
at of course hydro is every time. A good starting point for soil is weekly and for peat 2 times a week.

I am fairly certain I have run down the out of balance element in MC and it is not calcium it is sulfur. I am in the process of verifying this. I am willing to go out on a limb based on Bro-science. I have no sign of out of balance in my current grow as I have corrected for this. Here is the results of mathematical extrapolation from the Guaranteed Analysis.

3.5g MC v2. in one gallon of RO water. 500 - 600 PPM total is a good level for Autos. The Phosphorous is a bit too high but cannabis can tolerate up to about 100 without issues if everything else is good. Magnesium is barely in the green and sulfur is deficient.

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If you add a gram of Cal-Mg the total PPM is too high and sulfur is still deficient.

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If you add .5 gram of Magnesium Sulfate (Epsom Salt) You get a winning balance with the MC v2. You can use this in starting water up to about 200 PPM without calcium issues but it will be high.

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[Mañ'O'Green]

Ok right, so stick to around 500-550 MC (as I've done in the past with "better" success in past grows) but toss in 100PPM of epsom to round out the sulfur deficiency, right?

No not 100PPM of Epsom Salt ONE HALF OF ONE GRAM. Weigh it out, 3.5 grams of MC V2 in one gallon of water. Get a gram scale. It makes that much difference.

You only fertilize soil once a week. If you are growing in soil I recommend you go TLS and forget salt fertilizers all together. You fertilize Peat when it needs water like this - fertilize, PH water only, PH water only, PH water only, Repeat. Then monitor the plants to add a water only day or subtract one.

 

[jdm61]

No not 100PPM of Epsom Salt ONE HALF OF ONE GRAM. Weigh it out, 3.5 grams of MC V2 in one gallon of water. Get a gram scale. It makes that much difference.

You only fertilize soil once a week. If you are growing in soil I recommend you go TLS and forget salt fertilizers all together. You fertilize Peat when it needs water like this - fertilize, PH water only, PH water only, PH water only, Repeat. Then monitor the plants to add a water only day or subtract one.

So if I am following the directions on the bag as far as grams per gallon with the two-part megacrop, how many times should I be feeding a week? I’m up to almost 3/4 of a gallon of water per day with my Mexican Airlines plant. 1 m tall at 37 days and I would call it early flower because it has pubes everywhere. 3 gallon rain science bag. Lately I’ve been feeding it about a half gallon of pH water or feed in the morning in a quart in the evening. I’ll give it to half-gallon before I turn the lights off for five or six hours. Right now I’m doing the 2.5 g of part a and part B for late veg/early flower. The bag says go to 1.8 g of part B and 4.5 g apart a per gallon for full flower. Plus I have my bag up bud explosion.

 

[4d-Rock]

@BCBUDY you are missing the point about balanced nutrients. 3.5g MC with .5g Epsom Salt is where they are in balance. When you go with more they will be out of balance again.

I’ve seen people supplement with epsom and I have tried adding a bit here or there but I might have to try it for an entire run.

So if 3.5g MC and 0.5g Epsom is balanced per gallon. Do you scale each down proportionally for the earlier Veg, like when I’m starting at 1g or 2g per gallon MC, should I be including like .1 or .2g epsom or whatever the actual calculation works out to?

 

[Mañ'O'Green]

So if I am following the directions on the bag as far as grams per gallon with the two-part megacrop, how many times should I be feeding a week? I’m up to almost 3/4 of a gallon of water per day with my Mexican Airlines plant. 1 m tall at 37 days and I would call it early flower because it has pubes everywhere. 3 gallon rain science bag. Lately I’ve been feeding it about a half gallon of pH water or feed in the morning in a quart in the evening. I’ll give it to half-gallon before I turn the lights off for five or six hours. Right now I’m doing the 2.5 g of part a and part B for late veg/early flower. The bag says go to 1.8 g of part B and 4.5 g apart a per gallon for full flower. Plus I have my bag up bud explosion.

No the dirrections on the bag do not work for autos. What are you growing in?

I’ve seen people supplement with epsom and I have tried adding a bit here or there but I might have to try it for an entire run.

So if 3.5g MC and 0.5g Epsom is balanced per gallon. Do you scale each down proportionally for the earlier Veg, like when I’m starting at 1g or 2g per gallon MC, should I be including like .1 or .2g epsom or whatever the actual calculation works out to?

No you cannot scale down the MC it must be at about 3.5g to have a balance of N-P-K. You see how N and Ca are out of balance at 2g.

Mix it at 3.5g to .5g and then dilute it with water to get the PPM you want. This will keep it in balance.


People I need to know what you are growing in and which version of MC you are using! State it each time you have a question. It is just too hard to try to hunt that stuff down.

 

[elcoloan]

If you add .5 gram of Magnesium Sulfate (Epsom Salt) You get a winning balance with the MC v2. You can use this in starting water up to about 200 PPM without calcium issues but it will be high.

My Espom salts are 16% Mg - 13% S, would you mind putting these numbers in your spreadsheet to see how many gr i should be using at 3.5g of V2, please?

 

[Mañ'O'Green]

My Espom salts are 16% Mg - 13% S, would you mind putting these numbers in your spreadsheet to see how many gr i should be using at 3.5g of V2, please?

You will want to use .35g of that Epsom Salt.

 

[GeorgeCloney]

Mango,...explain it by ppm ratio...
most are lost with grams..

 

[4d-Rock]

No you cannot scale down the MC it must be at about 3.5g to have a balance of N-P-K. You see how N and Ca are out of balance at 2g.

Mix it at 3.5g to .5g and then dilute it with water to get the PPM you want. This will keep it in balance.

People I need to know what you are growing in and which version of MC you are using! State it each time you have a question. It is just too hard to try to hunt that stuff down.

Well that’s if you leave the epsom at 0.5g. It would be out of balance if you didn’t reduce the epsom by the same percentage.
What I was thinking is that if 3.5g/gal MC v2 1-part plus 0.5g/gal Epsom is considered balanced. Then say when I feed my 2 week old seedling at a lower dosage, I mix 2g/gal MC with 0.289g/gal Epsom. This would maintain the same ratio of nutrients at a lower strength. But doing a full strength mixture and diluting it to the required ppms would achieve the same.

I use a concentrated solution of MC since I often am making small batches. Since the dry mix can cause imbalance with the larger chunks.

Also, have been using Pro-mix HP.