How When & Why do you apply Epsom Salt

Owl Mirror · Sep 5, 2009

I have heard in a few conversations that if you have a magnesium deficiency you can spray a solution of Epsom Salt & water on the plant as a curative. I searched for specific information on how to concoct and apply this but, haven't found much direct info.
I thought I would create a thread for discussion of this topic.

What does Magnesium deficiency look like?
What method is best to apply this solution?
What exactly is this Epsom salt doing for the plant?

Tony Aroma · Sep 5, 2009

Funny, somebody just asked me in my grow diary why I use epsom salts. My answer was because they provide magnesium and sulphur. That would be the answer to your third question.

As far as what a magnesium deficiency looks like, check out the infirmary forum where there is a sticky with picts of all kinds of deficiencies.

As far as how to apply it, I mix 1/2 tsp per gallon of soil when preparing my soil. You can also dissolve it in water and use in your regular waterings or as a foliar spray, although I've never tried either of those as I've never had a magnesium deficiency AFAIK. Check out the organics forum for more info on using epsom salts.

Owl Mirror · Sep 5, 2009

Tony Aroma said:
Funny, somebody just asked me in my grow diary why I use epsom salts. My answer was because they provide magnesium and sulphur. That would be the answer to your third question.

As far as what a magnesium deficiency looks like, check out the infirmary forum where there is a sticky with picts of all kinds of deficiencies.

As far as how to apply it, I mix 1/2 tsp per gallon of soil when preparing my soil. You can also dissolve it in water and use in your regular waterings or as a foliar spray, although I've never tried either of those as I've never had a magnesium deficiency AFAIK. Check out the organics forum for more info on using epsom salts.

Hi Tony, are you saying you mix this salt directly in your soil ?
I had only heard of spraying it on the leaves.
How else can it be beneficial for growing our plants ?

Tony Aroma · Sep 5, 2009

Owl Mirror said:
Hi Tony, are you saying you mix this salt directly in your soil ?

Yes, that's exactly what I said.

How else can it be beneficial for growing our plants ?

Besides providing necessary magnesium and sulphur, I don't know. Epsom salts are just magnesium sulfate, so they really don't do much else other than acting as a source of those two elements.

Look up magnesium sulfate in wikipedia -- they describe its use and they even mention it in reference to growing cannabis.

MobbDeep · Sep 5, 2009

1.magnesium deficiency looks like all the leaves turn light green,BUT the VEINS are still dark green..this starts at the bottom of the plant,and quickly works its way up..cannabis uses high levels of magnesium..slow growth,light green leaves,and slight curling of the leaves UP indicate mag def..some call this "praying for magnesium"..http://www.gardenscure.com/420/attachments/nursery-reference/216711d1192608047-revised-complete-guide-sick-plants-ph-1134magnesium-1.jpg

2.always use as a spray..mixing in soil,or using as soil drench doesnt work as fast,and can do more harm than good..mix 2 teaspoons per water bottle filed with HOT WATER..to dissolve the epsom salts better and evenly..thougroughly spray plants,especialy the bottom of the leaves,during lights off..or during the cool temps..as temps get higher,the stomata close to prevent excess water loss

3.Store bought epsom salt is pure,uncut magnesium sulphate..it is a VERY fast acting remedy for mag deficiencies..it is a very valuable thing to have for the cannabis grower,and can be bought in walgreens or any pharmacy store..in the medicine aislt,as people use it for thier stomachs..

Owl Mirror · Sep 5, 2009

MobbDeep said:
1.magnesium deficiency looks like all the leaves turn light green,BUT the VEINS are still dark green..this starts at the bottom of the plant,and quickly works its way up..cannabis uses high levels of magnesium..slow growth,light green leaves,and slight curling of the leaves UP indicate mag def..some call this "praying for magnesium"..http://www.gardenscure.com/420/attachments/nursery-reference/216711d1192608047-revised-complete-guide-sick-plants-ph-1134magnesium-1.jpg

2.always use as a spray..mixing in soil,or using as soil drench doesnt work as fast,and can do more harm than good..mix 2 teaspoons per water bottle filed with HOT WATER..to dissolve the epsom salts better and evenly..thougroughly spray plants,especialy the bottom of the leaves,during lights off..or during the cool temps..as temps get higher,the stomata close to prevent excess water loss

3.Store bought epsom salt is pure,uncut magnesium sulphate..it is a VERY fast acting remedy for mag deficiencies..it is a very valuable thing to have for the cannabis grower,and can be bought in walgreens or any pharmacy store..in the medicine aislt,as people use it for thier stomachs..

Thanks MobbDeep, so "2 teaspoons per water bottle" and spray the plant just prior to lights out.
Is it better to spray the top of the leaves or try spraying the underside of the leaves ?
Is this to be used only as a remedy or is it used consistently throughout the grow ?
Should you avoid spraying BUDs ?

geopolitical · Sep 5, 2009

I use a dose of 1/2 to 1 tsp per gallon dissolved into warm water.

For foliar spray I add just a tiny drop of soap to the whole thing and shake like hell right before spraying. I've used "wetting" agents in the past but our current dish soap is nontoxic and the plants seem to do well with it. Generally though I'll use it as a soil drench.

Adding correct amounts of dolomite lime or fertilizing with a complete fertilizer will eliminate most of the need to do this however.

Spraying buds will do them no harm as long as your humidity isn't too bad and they dry quickly.

Owl Mirror · Sep 5, 2009

Tony Aroma said:
Yes, that's exactly what I said.

Besides providing necessary magnesium and sulphur, I don't know. Epsom salts are just magnesium sulfate, so they really don't do much else other than acting as a source of those two elements.

Look up magnesium sulfate in wikipedia -- they describe its use and they even mention it in reference to growing cannabis.

Thanks Tony!

(magnesium is an essential element in the chlorophyll molecule).

http://www.epsomsaltcouncil.org/

MobbDeep · Sep 5, 2009

OWL MIRROR...

epsom salt is BEST used as a very fast acting remedy..but you can DEF benefit from folair feeding it about once per week..YES pay sepcial attention to the bottom of the leaves,as that is where most of the stomata is located..and do it either at light off,or a minute of two before the lgihts go off..you can certainly spray buds,but I wouldnt spray ANYTHING to my buds..just focus on the leaves,as I doubt there are ANY stomata on the buds,just the leaves..

i dont reccomend using as a soil drench,as this can cause problems..

another GREAT foliar feed that i use is maxicrop lqiuid seaweed..this is a MUST HAVE for folair feeding to cannabis..

LolaGal · Sep 5, 2009

Splurge and buy some CalMag Plus instead. Works much better.

epsom SALT and plants don't get along as well.

Alittle Cal Mag and no deficiencies in the first place. Preventative maintainence.

HortProOrganics · Sep 5, 2009

LolaGal said:
Splurge and buy some CalMag Plus instead. Works much better.

epsom SALT and plants don't get along as well.

Alittle Cal Mag and no deficiencies in the first place. Preventative maintainence.

In large amounts, yes, I agree, it can inhibit production, and can increase, if not used correctly, problems. In large scale applications, and provided the preservation of the micro-life underneath the top soil as well as the plants vascular system, Epsom salts can help a great number of plants and their needs. Run on sentence, I apologize though. I also agree, CalMag and other products within the limestone realm may offer better results.

Magnesium helps with the Chlorophyll production and maintenance, as well as cellular health. Increased flower production may be influenced, but it not a typical supplemental tool. High flowering or fruiting plants like Rosa, Cannabis, Vaccinium, Capsicum, Rubus, etc. etc. will all benefit from mag supplements, within reason

Sulfur, without writing a book, is responsible for overall growth of the plant, reducing environmental stress, and helping increase pest and disease resistance.

I apply once every 2 to 4 weeks, when needed, but I have a great deal of magnesium and sulfur ingredients within my living soils and teas.

LolaGal · Sep 5, 2009

sulphur def. is extremely rare in cannabis.

Mag. def can be prevented by watering with CalMag Plus once or twice during veg.

A quart will last a hobby grower for a long time.

(It's really BRAWNDO, sshhh don't tell anybody

We all know BRAWNDO's got what plants crave.... )

MobbDeep · Sep 5, 2009

HOTPROORGANICS excellent point..epsom salt should be considered for organic grows,as magnesium sulphate is essentially pure salts..such as any mineral nutrient..it can harm the microbial life in the soil..on top of that,it can alter ph,and do more hram than good when applied as a root drench,,but when applies as folair feed..theres no chance of doing harm..

i always keep some epsom salt around..and give them a good foliar feed..its very beneficail during both veg and flower..especualy during veg..

HortProOrganics · Sep 6, 2009

I totally agree with the foliar feeding, don't get me wrong at all. I do, when its necessary, but I also find that deficiencies in soil systems can always be prevented by good microbial life surrounded with micro-nutrients and other flora.

ibjamming · Sep 6, 2009

If you lime the soil...or top dress with it...you're adding "natural" Cal/Mag. Why buy a more expensive product when you don't have to? Mix dolomite lime with your soil from the beginning and you won't have to worry about it. It also neutralizes ph to close to 7 as a bonus.

Hydropimp · Sep 6, 2009

I did add lime to the soil and still got mag def does any1 use it in every watering? or only when feed?

Owl Mirror · Sep 6, 2009

LolaGal said:
Splurge and buy some CalMag Plus instead. Works much better.

Sure but, can you help me decide what I should do without this month?
Should I not buy lunch meats or that extra TV dinner?
Maybe I could just not buy my medicines, that might equal the cost of this CalMag Plus.

LolaGal · Sep 6, 2009

Owl Mirror said:
Sure but, can you help me decide what I should do without this month?
Should I not buy lunch meats or that extra TV dinner?
Maybe I could just not buy my medicines, that might equal the cost of this CalMag Plus.

I would do without whatever it took, so I did not lose my valuable crop of MJ, which probably will pay you back 1000000 the cost of the $20 bottle of CalMag.

It's like comparing a candle to a searchlight..... they both light up the dark.

My MJ plants deserve the 14 cents worth of CalMag I use on them during their lifetime.

Sure, go ahead and use cheap Epsom Salts on yer grow!

I was trying to help ya! Put those salts dirrectly into the soil like you have been told and you will have trouble.

Ever read in the Bible where they didn't want thiings to grow? They salted the ground.

So do without that baloney sandwich if that is what it takes... your plants will pay you back for it.

MobbDeep · Sep 6, 2009

which is why i told him not to use as a soil drench..imho using cal mag plus is a simply luxury and simply not nesscecary,dedending on which fertilzier you use,there is planty cal-mag..however IF you get a deficiency,then simply use epso salts to fix it..so hard work,no $30 a bottle,why spend that when you can get PURE magnesium sulphate for like 3 dollars that you can buy in ANY store,and will last SEVERAL grows..

like i said,maintain your plants healthy with a weekly folair feeding of epsom salts..DO NOT use as a soil drench man..like lolagal said,this is pure salt basically,and can def harm your plants if used as a soil drench..just foliar feed..then wash the leaves with a foliar feed with pure water..

Owl Mirror · Sep 6, 2009

MobbDeep said:
which is why i told him not to use as a soil drench..imho using cal mag plus is a simply luxury and simply not nesscecary,dedending on which fertilzier you use,there is planty cal-mag..however IF you get a deficiency,then simply use epso salts to fix it..so hard work,no $30 a bottle,why spend that when you can get PURE magnesium sulphate for like 3 dollars that you can buy in ANY store,and will last SEVERAL grows..

like i said,maintain your plants healthy with a weekly folair feeding of epsom salts..DO NOT use as a soil drench man..like lolagal said,this is pure salt basically,and can def harm your plants if used as a soil drench..just foliar feed..then wash the leaves with a foliar feed with pure water..

It does make sense that it is the leaves which need the trace amounts and not the entire root system. The reason I started this discussion is because I was grocery shopping and noticed the container of Epsom Salt on the shelf. It was under $3 so I bought it. If anything, I can soak my tired and cramped feet ;>}
I had remembered people mentioning this solution yet, when I did a search didn't find any good discussions on it's use. Just a few honorable mentions of being used.

I haven't had many problems so far, knock on wood.
Now I know that having this cheap product available, if the problem arises I can simply give the plant a few spritz before she goes to bed and hope she feels better in the morning ;>}

Thanks !

btw lola, I realize there are all these products for sale. I simply can't see spending $30-120 on all those chemicals and preparations if I can go down to my favorite hardware store and pick up stuff that works just as well.

Then again, I'll probably never achieve perfection in my growing skills and style.
I'm still learning and I hesitate spending $30 on a bottle of something, only to use a few times when I can spend $3 and use it or not.

If I spent $30 and never had the need to use the contents of the bottle, I would not be happy.
This way I have a $3 container sitting and, I just might soak my feet some night.
Can't do that with CalMag, or can you ?

I'm sure it's a great product and, it might even make the plants that much better through the investment but, I'll pass for now.

How When & Why do you apply Epsom Salt

Active member

Let's Go - Two Smokes!

Active member

Let's Go - Two Smokes!

Member

Active member

Vladimir Demikhov Fanboy

Active member

Member

LolaGal

Member

LolaGal

Member

Member

Active member

Active member

Active member

LolaGal

Member

Active member