Foliar spray VS Cal/mag

I’m just about to wrap up my first ever (successful) grow. If everything goes well in the next month I should be able to say I finally grew cannabis. At this point I’m lucky to be able to say anything with all the damn mistakes I made. That being said, one big mistake I made was mistaken cal/mag deficiency with over/under watering. I know I know, classic noob mistake. But I’ve learned.

When I was finally able to get the cal/mag deficiency under control, I could have kicked myself because just last week I had something arrive which could have saved me some trouble. The foliar CarbCal spray from Xtreme Gardening. However, I started to question if a foliar spray is a good substitute for a Cal/Mag mix like Bush Dr or Roots Organic Cal/Mag.

My question is, can you skip a Cal/Mag feeding for a foliar spray and is it enough to focus on one and not the other?

I.E. If you use a Cal/Mag mix do you still need a foliar spray OR can you use ONLY the foliar spray in absence of the Ca;/Mag mix?
Will the Calcium still reach every part of the plant or where it’s needed or is that done ONLY thru root zone application?

Thanks in advance for the read.
Everyone have yourselves a GREAT week.

Calcarb is just calcium carbonate so it wouldn’t be a substitute for cal mag. Although you can use cal mag as a foliage spray. But you’ll want to avoid any foliar spray in flower.


Foliar feeding gives quick application of the Ca Mg where it is immediately available but be careful during flowering as powdery mildew can take hold or can have issues with light burn depending on your lights.

Feeding Ca Mg with water feed is somewhat slower (depends on product used) and will provide the needed nutrients too.

You can do both but I would recommend primarily mixing with water and feeding.

Pictures would help us help you better diagnose things

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I didn’t consider the other minerals and nutrients when referencing the spray. Good call pointing it out. I think I’m going to try the spray on my “Rags” seeds and use the Cal/Mag mix as a regular feeding when going from Veg to Bloom. I don’t want to chance hurting decent ILGM seeds. I’ll experiment on the street rags seeds.

I bought myself Roots Organic Cal/Mag. Havn’t used it yet buy based upon what I’ve read, it’s one of the dependable go-2’s. I got that, Rhino skin and Dolomite Lime.

I have Ocean Floor by FF and I know there isn’t an active culture of Myzo fungus, unlike Happy Frog. I want to be able to add the Myco as soon as possible to get the ball rolling. My thinking is if I’m able to use the Great white or Xreme Gardening prior to seedling, add the Mycos chum to feed the microbes, THEN plant the seedling. I’ll have a nice colony of fungi and bacteria waiting for the roots.

Is this just wishful thinking or can it be done?
Also, is it safe to pH adjust Myco chum or is it meant to be applied as is?

I recommend a plant therapy spray if you use the foliage method to remove powder mildew.

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I use great white and have never needed anything more than just sprinkling it in the transplant hole and on the root ball during transplant.

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Any updates on your plants I’m looking to for a leaf spray.

The old batch was a hit and miss but I didn’t end up using any Foliar spray.
I ended up using a Cal/mag mix in my watering schedule. Turned out pretty
good. This is my newest grow and it’s going great so far.

Gorilla Glue times 2 - Beginner / Grow Journals - I Love Growing Marijuana Forum by Robert Bergman

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