epsom salt or dolomite lime
- Thread starter carokann
- Start date
Pon De Floor
Active Member
if you're going for a calmag solution, then dolomite would be the way.
epsom salt is just the fastest absorbing for magnesium from what i understand.
epsom salt is just the fastest absorbing for magnesium from what i understand.
Yes. I use both and it works quite well.
In the future though, mix them into the soil before use. Both work much, much better that way. Both are slow release and take a while to start working.
Epsom Salts is a good quick source of Mg if needed, but the lime and greensand will do better for you in the long run.
Wet
Not at all if you don't go crazy with it.
I'm running LC's soiless mix #1 and add blood, bone, kelp, greensand and dolomite lime. The basic mix is peat moss, perlite and worm castings.
A very good 'water only' mix that isn't as hot as super soil.
Wet
Cann
Well-Known Member
oyster shell flour > dolomite
gypsum > epsom salts...and yes I know that gypsum is calcium sulfate whereas epsom salts are magnesium sulfate...but IMO Mg is very rarely a problem..plants need much more Ca than Mg.
for long term soil applications dolomite is preferred, but indoors where soil will be recycled and reamended I prefer oyster shell...less chance of overdoing it with the "liming" agent.
also rock dusts can be your friend in large amounts - quality rock dust will contain all the nutrients you need at low levels. this includes things like Ca and Mg...
my 2 cents = stay away from dolomite, bone, and blood meal - lean towards oyster shell, rock dusts, alfalfa meal (for N), and kelp meal for trace minerals. theres a lot of ways to f*** up with dolomite, blood meal and the like.
oh yeah and "Ca/Mg issues" are rarely actually Ca or Mg....in my opinion
gypsum > epsom salts...and yes I know that gypsum is calcium sulfate whereas epsom salts are magnesium sulfate...but IMO Mg is very rarely a problem..plants need much more Ca than Mg.
for long term soil applications dolomite is preferred, but indoors where soil will be recycled and reamended I prefer oyster shell...less chance of overdoing it with the "liming" agent.
also rock dusts can be your friend in large amounts - quality rock dust will contain all the nutrients you need at low levels. this includes things like Ca and Mg...
my 2 cents = stay away from dolomite, bone, and blood meal - lean towards oyster shell, rock dusts, alfalfa meal (for N), and kelp meal for trace minerals. theres a lot of ways to f*** up with dolomite, blood meal and the like.
oh yeah and "Ca/Mg issues" are rarely actually Ca or Mg....in my opinion
Rising Moon
Well-Known Member
Commonly over looked sources of minerals can be found at health food stores and pottery shops...
Never buy bottled Cal/Mg again...
French Green Clay Mineral Content
Rhassoul Clay Mineral Content
Use as a foliar at 1 tea spoon per gallon.
Never buy bottled Cal/Mg again...
French Green Clay Mineral Content
Rhassoul Clay Mineral Content
Use as a foliar at 1 tea spoon per gallon.
AliCakes
Well-Known Member
Epsom salt is a great fast acting magnesium supplement, but it will raise the salt content of the soil. Too much salt will kill your micro cultures in the soil - this will drastically effect nutrient uptake by your plants. Most of the soil is not bio available to the plant without the help of the micro flora and fauna.
Dolomite lime is simply a high magnesium limestone. While it does contain a lot more magnesium than calcitic lime, it is still often nearly half calcium carbonate and WILL RAISE YOUR PH. If you are using the ground up version, it often raises pH drastically. While nature does buffer the pH somewhat, this takes time.....lots of time. Don't let people fool you into believing that pH doesn't matter. Plants cannot uptake nutrients outside of a certain pH window. This is true in organic and conventional gardening, whether you are growing flowers, vegetables, or cannabis.
Having said that, I have both on hand, but my main magnesium supplement is homemade vermicompost - green leafy vegetables are full of magnesium. A worm bin is truly a gardeners best friend. Use the amendments you want, but try to understand what it is that you are putting on your plants and how it works with and against the natural environment you are trying to create.
Cann is also a vermicomposter - which is why he says magnesium isn't an issue. People who pull plants from their soil and do not replace the ingredients removed often do have magnesium issues.
Rising Moon is dead right using mineral clays instead of the more common supplements. I have not personally used them, but biologically - they are better choices than the epsom salts or dolomite ever could be.
Dolomite lime is simply a high magnesium limestone. While it does contain a lot more magnesium than calcitic lime, it is still often nearly half calcium carbonate and WILL RAISE YOUR PH. If you are using the ground up version, it often raises pH drastically. While nature does buffer the pH somewhat, this takes time.....lots of time. Don't let people fool you into believing that pH doesn't matter. Plants cannot uptake nutrients outside of a certain pH window. This is true in organic and conventional gardening, whether you are growing flowers, vegetables, or cannabis.
Having said that, I have both on hand, but my main magnesium supplement is homemade vermicompost - green leafy vegetables are full of magnesium. A worm bin is truly a gardeners best friend. Use the amendments you want, but try to understand what it is that you are putting on your plants and how it works with and against the natural environment you are trying to create.
Cann is also a vermicomposter - which is why he says magnesium isn't an issue. People who pull plants from their soil and do not replace the ingredients removed often do have magnesium issues.
Rising Moon is dead right using mineral clays instead of the more common supplements. I have not personally used them, but biologically - they are better choices than the epsom salts or dolomite ever could be.