When to use epsom salts in your grow?

[PipeCarver]

Hi, I've been reading some info on using epsom salts in your grow. Is it something to use on a regular basis or just when you see problems occur? Does anyone here use it regularly or sporadically? Is there a tell from your plants to when its needed? In flower or in Veg? so many questions any information would be great, thanks.

 

[az2000]

Hi, I've been reading some info on using epsom salts in your grow. Is it something to use on a regular basis or just when you see problems occur? Does anyone here use it regularly or sporadically? Is there a tell from your plants to when its needed? In flower or in Veg? so many questions any information would be great, thanks.

I would only use it in a soil grow if there were signs of magnesium deficiency. 1/4 tsp/gal for minor deficiency, 1/2 tsp/gal or significant def.

If your tap water had an imbalance of Ca & mg (which should be 2:1 to 4:1 ration, epsom salt could be used to balance that. If you used reverse-osmosis water which has almost no minerals in it, epsom salt and gypsum could be added to it to get a good ratio and about 150ppm before adding nutrients. But, it's more common to mix tap water into the RO water to get that (when people have very high ppm tap water).

People who grow using LED grow lights sometimes add mg to every feeding because they feel the light causes the plant to use more mg. I grew with such lights an never did that. It may depend on the light.

I made the attached PDF for myself (to reference when I need to use epsom salt or gypsum).

Hyroponics growers use epsom salt a lot. They calculate their nutrients using a free program called Hydro Buddy. They'll use raw products to get the percentages they need. Epsom salt is something they'll use to get where they want to be. In soil, it's expected Ca and Mg will exist in the soil (dolomite lime.).

 

[PipeCarver]

I would only use it in a soil grow if there were signs of magnesium deficiency. 1/4 tsp/gal for minor deficiency, 1/2 tsp/gal or significant def.

If your tap water had an imbalance of Ca & mg (which should be 2:1 to 4:1 ration, epsom salt could be used to balance that. If you used reverse-osmosis water which has almost no minerals in it, epsom salt and gypsum could be added to it to get a good ratio and about 150ppm before adding nutrients. But, it's more common to mix tap water into the RO water to get that (when people have very high ppm tap water).

People who grow using LED grow lights sometimes add mg to every feeding because they feel the light causes the plant to use more mg. I grew with such lights an never did that. It may depend on the light.

I made the attached PDF for myself (to reference when I need to use epsom salt or gypsum).

Hyroponics growers use epsom salt a lot. They calculate their nutrients using a free program called Hydro Buddy. They'll use raw products to get the percentages they need. Epsom salt is something they'll use to get where they want to be. In soil, it's expected Ca and Mg will exist in the soil (dolomite lime.).

Ya okay, so that's not unless theirs a need and not to use as some preventive problem solving super solution. Can it cause problems when used incorrectly? I'd read somewhere that it adds needed sulfur to flowering plants and it's not something that will cause problems if used. I use well water by the way.

 

[az2000]

Ya okay, so that's not unless theirs a need and not to use as some preventive problem solving super solution. Can it cause problems when used incorrectly? I'd read somewhere that it adds needed sulfur to flowering plants and it's not something that will cause problems if used. I use well water by the way.

Ca and Mg should be available together in a range from 2:1 to 4:1 (ca to mg). So, if you only use epsom salt as a preventative, you run the risk of creating an imbalance with calcium.

If I were going to feed Mg for sulfur, I'd add some gypsum to create the balance described in that PDF (my first post). Gypsum has sulfur too. So, you'd use less epsom salt that way, and create a better balance. (Or, just use a "calmag" product for convenience. I wouldn't. But... that's what most people do. Using epsom salt and gypsum is cheaper. You need a fairly accurate sub-gram scale, though.).

 

[Beachwalker]

Hi, I've been reading some info on using epsom salts in your grow. Is it something to use on a regular basis or just when you see problems occur? Does anyone here use it regularly or sporadically? Is there a tell from your plants to when its needed? In flower or in Veg? so many questions any information would be great, thanks.

You might want to search Jack's 3-2-1 recipe for more info on epsom salts, and it has other possible uses too. I also use it as a foliar spray with great success because it acts quickly at the first sign of a magnesium issue, and it also provides sulfur which some say helps bring out the scents in the finished bud, good luck

 

[Jimster]

I feel that it is not usually needed unless using RO/Distilled water, at least for soil growing. Hydro is a different beast altogether. Too much Cal-Mag can raise your Ph and cause lockouts... if used excessively. Wood ashes are a good substitute as they add a lot of minor nutrients, but like any addition, use with restraint and common sense. A tablespoon or two worked into the soil will provide most of what you need.

 

[PipeCarver]

Thanks ya'll I needed that!

 

[cemchris]

I use epsom all the way from veg to flower. Part of my Nute makeup.

 

[bluedabadee]

I use epsom all the way from veg to flower. Part of my Nute makeup.

Including the late flowering period? Thanks!

 

[NorGrower]

I just experimented with my own nutrient mix. A mix of Yara's Kristalom and Calcinit, and RawP and Epsom. Each substance's weight changing over the course of the grow. I used Epsom during week 0-8, assuming a 12 week grow.
I increased the amount of Epsom gradually from X to 2X from week 1 to 5 then back down to 0.8X week 8, then nothing for the remaining weeks.

Sadly, I don't have much to compare with but from what I could see, the plant thrived.

 

[JWM2]

I use Epsom salts as needed. I sometimes use it as a soil mix-in when transplanting and top dressing when I feel they need a decent boost. It’s pretty forgiving.

 

[cemchris]

Including the late flowering period? Thanks!

I run the same nutes all the way from start to finish. So yes if I'm not flushing I'm feeding, including epsom.

 

[oldskol4evr]

i find that the sulfur in it also helps adjust hard water ph, the magnesium is like drugs to your plants,you can over do it though

 

[Aqua Man]

yup I generally run a gram per gal and sometimes 2 gram per gal. I find cal mag and most nutrients to have a bit to much of a gap in ratio of cal to mag.