Gypsum top dress amount

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Anyone know the amount of gypsum to use as a top dress amendment for Calcium deficiency? I’m at a friends and gypsum is what is on hand. Been a while but as I remember it’s about 1 tsp per gal of soil.
 
Anyone know the amount of gypsum to use as a top dress amendment for Calcium deficiency? I’m at a friends and gypsum is what is on hand. Been a while but as I remember it’s about 1 tsp per gal of soil.
1 to 2 teaspoons for calcium deficiency is what I found in an internet search. If its what you have on hand, it will work but it might take a little bit of time to become available. There's other things I would be reaching for first (powdered dolomite for example) if its on hand. It will also supply magnesium.

Personally, I use epsom salts during veg and cal/mag during flower. (There's even been times I've used both cal/mag and epsom salts during flower too.) For me, it's been the simplest way to avoid both calcium and magnesium deficiencies indoors.
 
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He has been using roots organic calmag liquid and epsom.
I switched from roots organic "dry amendments" because I struggled with similar issues to what you're describing. I'm using GH trio + epsom salts and calmag and I rarely see those issues anymore. I chalked it up to the organics not breaking down and becoming available soon enough. With that said, a nice round of beneficial microbes might improve his situation.
 
I used the RO dry stuff for one or two grows and found I was not quick enough to diagnose my plants to feed them properly without issues.
It seemed slow motion.
 
I switched from roots organic "dry amendments" because I struggled with similar issues to what you're describing. I'm using GH trio + epsom salts and calmag and I rarely see those issues anymore. I chalked it up to the organics not breaking down and becoming available soon enough. With that said, a nice round of beneficial microbes might improve his situation.
Great white was topped dressed earlier in week. Microbes are there.
 
Anyone know the amount of gypsum to use as a top dress amendment for Calcium deficiency? I’m at a friends and gypsum is what is on hand. Been a while but as I remember it’s about 1 tsp per gal of soil.
I use it in my mix at about 1tbs \ gal, I go by guess work and approximations , Promix, perlite, myco's, gypsom,azomite,worm castings. By doing that I don't need to feed for a month
1 to 2 teaspoons for calcium deficiency is what I found in an internet search. If its what you have on hand, it will work but it might take a little bit of time to become available. There's other things I would be reaching for first (powdered dolomite for example) if its on hand. It will also supply magnesium.

Personally, I use epsom salts during veg and cal/mag during flower. (There's even been times I've used both cal/mag and epsom salts during flower too.) For me, it's been the simplest way to avoid both calcium and magnesium deficiencies indoors.
yes that's me too although I don't add extra mag once I start with Cal/mag
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Saw this......

While gypsum can be used in certain situations to improve soil structure, most gardeners don't need to use it because it's often not necessary, can potentially strip essential nutrients from the soil, and may only be beneficial for very specific soil types like heavy clay with high salt content; for most gardens, adding compost or organic matter is a better option for improving soil health.

Reasons to avoid using gypsum in most gardens:
  • Unnecessary for most soils:
    Most garden soils don't have a significant need for the calcium and sulfur provided by gypsum, especially if you regularly amend with compost.

  • Potential nutrient depletion:
    Applying gypsum can leach out other essential nutrients like magnesium, potassium, and iron from the soil, leading to deficiencies.

  • Limited impact on soil pH:
    Unlike lime, gypsum does not significantly change soil pH, so it won't help if your soil is too acidic.

  • Slow acting:
    Gypsum works slowly, meaning you may not see noticeable improvements in soil structure for a long time after application.

  • Requires soil testing:
    To ensure gypsum is needed, always perform a soil test to check for calcium levels and salt content before applying
 
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