Magnesium Question

[Simpleton]

Is there a process that makes magnesium available in the soil from the degradation of organic matter? What I mean is, does a basic bagged soil (I use SuperSoil), without an added mag source, have the potential on it's own to provide mag from it's organic material?

Does it need to be added to an organic flowering mix?

If so, what would be a good source?

If using Epsom salt in solution, how often and what concentrations should be used?

Thanks

 

[quadracer]

Yeah, that is the process. Magnesium becomes available when organic material breaks down. Soils should have magnesium contained in it, but adding some compost or kelp will ensure there is enough.

Here is a little info from an organic gardening book on magnesium:

"Another element needed in much larger quantities as phosphorus. It is also a constituent of cholorophyll so a deficiency causes yellowing, which starts between the veins of the leaves. The deficiency generally affects older leaves first.

"A Magnesium deficiency is sometimes caused by plants not being able to take up magnesium from the soil, perhaps because there is too much potassium present. This can also happen if the soilk structure is poor if there is insufficient organic matter in the soil.

"Treating a magnesium deficiency: Apply a dressing of seaweed meal, liquid seaweed, or liquid animal manure."

 

[Suby]

I generally nip the whole magnesium and calcium thing in the butt by using dolomite lime at 2TBS per gallon of soil mix.
If you didn't use it then epsom salts apllied as a foliar at 1TSP per gallon of fresh water can also be a good alternative.

As quadracer posted above magnesium is made available organically when any organic compound that contains magnesium in your soil mix is broken down.
Use the powdered dolomite and the above rate and kiss your worries goodby

Peace
Suby

 

[BurnOne]

Epsom salts doesn't have any calcium in it. Use dolomite.
Burn1

 

[Simpleton]

I used oyster shell lime.

Will this have the same effect?

 

[BurnOne]

Simpleton-
No. Oyster shell lime will not provide the magnesium that dolomite will. It will provide calcium. I'm not sure if it's as much as dolomite though.
Burn1

 

[Suby]

I used oyster shell lime.

Will this have the same effect?

You can use half dolomite and half oyster shell if you like.

S

 

[muddy waters]

half oyster shell half dolomite might even be a better bet, as i've been reading that it is preferable to have a little bit more calcium than magnesium in the substrate. when i see red petioles and the like i usually just go with the foliar spray mentioned above using epson salts and a little bit of molasses as a sticker/spreader.