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Mag Deficiency, Ok To Foliar Spray During Week 4 Of Flower?

Hey guys,

I grow in soil 35% Perlite, 65% FFOF using AN nutes.

I have a magnesium deficiency showing on my leaves going into week 4 of flower. I've seen some sources say to foliar with water + Epsom salt or cal-mag. Just not sure if I should foliar this late into flower with buds.

Researching fixes I've seen remedies including flush (3x pot volume) to get ph right, just dose up Cal-Mag next couple of feeds, add epsom salt to feed, foliar with some epsom salt.

Any recommendations would be great thanks!
 
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Just mix it in water and water the plant with it. I water with calmag regularly. I wouldn't spray anything on buds. I'm about week 4 now. I feed calmag regularly. Every few feedings just to keep the levels up. I think plants want more calcium in flower. Epsom is straight magnesium. So if you are 100% sure it's mag deficiency you can use that. Other than that I'd give a calmag feeding not foliar.
 
Just mix it in water and water the plant with it. I water with calmag regularly. I wouldn't spray anything on buds. I'm about week 4 now. I feed calmag regularly. Every few feedings just to keep the levels up. I think plants want more calcium in flower. Epsom is straight magnesium. So if you are 100% sure it's mag deficiency you can use that. Other than that I'd give a calmag feeding not foliar.
Thanks, I dosed down my cal-mag first weeks of flower to try to max out my base and additives without going over 1200ppm. I'm think I'm paying for doing that now.

Last feed was yesterday in which I dosed the Cal-Mag at around 60% strength, when I was literally doing 25% thru the first 3 weeks.
 
Some additional info: I forgot to pH my water first feed of flower, I know that my non pHed nute feed is 5.9-6.0 so pH was a bit low for soil to start off. I normally pH my nute feed to 6.5.
 
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Im in soil and feed calmag regularly. Like 2-3 times a week. 1 ml in with my nutes. I have never checked ppm. Using advanced nutrients and ph comes out 6.4 like clockwork. I feed daily now and run clean water every 3-4 feedings. Plants are 34-45 inches 2-3 ft around in 3rd week flower and very healthy. Using bud blood at little over 100% directed dosage along with bud candy and rhino skin. I mix the rhino and bud candy in one batch and the bud blood n calimagic in a seperate batch. I use the hot stuff first then the candy and rhino skin. I do not overwater to where it comes out the bottom of my 5 gal buckets. They go dry daily. I'm new to indoor but the plants seem to love it.
 
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Why hit cal/mag when you're only magnesium deficient? There are plenty of products on the market that focus on magnesium and sulfur (two of tye catalysts for essential oil production in the flowering state) without the calcium.
 
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Some additional info: I forgot to pH my water first feed of flower, I know that my non pHed nute feed is 5.9-6.0 so pH was a bit low for soil to start off. I normally pH my nute feed to 6.5.
You've got 35% perlite which means you're 35% hydro 5.9-6.4 would likely be ideal in that mix. Make sure your meter is calibrated and back up your reading with a second trusted measuring device like say strips. 99% of nute deficiencies newer growers encounter aren't because of lack of anything. I guarantee every single macro/micro nute required by your plants is in the combination of salts you're throwing at them. It's just out of balance, be it ph or a salt build up. Too much of one salt interferes w another's uptake and a deficiency results. Getting everything back in check with heavy runoff of a nicely balanced mixture will get you back in check fastest. Frequent runoff helps keep imbalances from accumulating as plants will never use everything you give them, what remains accumulates causing imbalances. 1200 ppm is just unnecessary....Foliar feeds would be a bandaid to your situation not a fix. Don't get me wrong foliar feeds are great before bud set but anything you spray on buds will stay there. It is by no means all taken up and residue will remain. I'd prefer not to smoke calcium nitrate salt. Plus your problem likely resides in your medium. Good luck :)
 
That's exactly what i just did now! Week 4.5 flower and added Botanicare Mag 1.0% Water soluble solution. Its recommended as a great foliage spray additive. I sprayed the entire plant except direct on buds and then poured the rest in the soil post feeding. (foliage spray - 4 oz) (Poured other 26-27 oz in soil direct) (TOTAL-1L of PH'd water, 2ml Botanicare, 2ml/2ml part A/part B nutrients.) Had my outside fan on the plant when i sprayed it to make sure water didn't sit. Dried in 30 minutes and could see instant impact. Obviously not something you want to do often though because of mold and such but if you need it, get it. I am also using AN nutrients.
 

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