How much calcium and magnesium?

[Ray]

That's interesting. Is that Greencare-produced product?

Back to an earlier of your comments, if you are using the MSU Well Water formula, they do not add calcium or magnesium to that formula, so maybe the RO formula would be a better choice.

[silken]

Originally Posted by Ray

That's interesting. Is that Greencare-produced product?

Back to an earlier of your comments, if you are using the MSU Well Water formula, they do not add calcium or magnesium to that formula, so maybe the RO formula would be a better choice.

Ours is a GreenCare product. We buy two formulas (RO/rain and well/tap water). Our society buys them in larger quantities and then re-packages in smaller containers for our members. Around here, we don't have a lot of supplies so I and another society member are in charge of sourcing and ordering supplies for our society.

I have both versions because I used to water with rain water, but it was too much trouble collecting enough to last me all winter for 150 orchids in our climate. I believe the well/tap water form has 2% calcium and some magnesium but not sure although I did see it listed at one time.

Since I've been adding a Cal/Mag liquid in small amounts to my watering, I see a marked improvement so I will carry on as I have been doing. I occasionally change fertilizers too just to cover all my bases.

[Ray]

Well, 2% Ca is certainly more than your plants are getting from even the MSU RO formula (which my observations say is enough), and probably the cal/mag supplement, as well - although that sounds like a VERY high level for ground water - most are well under 100 ppm.

[silken]

Originally Posted by Ray

Well, 2% Ca is certainly more than your plants are getting from even the MSU RO formula (which my observations say is enough), and probably the cal/mag supplement, as well - although that sounds like a VERY high level for ground water - most are well under 100 ppm.

I meant the analysis of the well/tap water form of MSU says 2.0% calcium content and the RO/rain water version of MSU is 8.0% calcium

[Ray]

I stand corrected!

I started carrying the stuff when it was first released, and at that time it contained no calcium. It must have changed somewhere along the way, as I just looked at a label from my latest shipment, and it does, indeed, contain 2% Ca.