Adding calcium to orchids

[Kailyn]

hello all
I am wondering about ways to add calcium to your watering/fertilizing regime. most of what I read advises you to buy a fertilizer already containing calcium but I can't seem to find any and am not inclined to buy anymore types of fertilizer to try at the moment as I have at least 3 different kinds floating around under my sink... would crushed up human calcium supplement do anything? I've read about eggs shells but it seems pretty split opinions on if they work or not. One website said diluted milk but that seems like a rot invitation to me....suggestions?

[kindrag23]

I quite honestly broke down and bought a liquid calcium supplement and my plants seem to be so much happier ever since. I use magical liquid feed as an additive to my fertilizer regimen and have seen happier plants with almost no signs of bacterial/fungal issues since.

[isurus79]

Yep, Ca supplements are cheap and common at the store. Just be sure it is a Ca and Mg combo, not just Ca.

[Orchid Whisperer]

Another good calcium source is gypsum, 1 tsp. per gallon. You can usually buy bags of pelleted gypsum in lawn & garden centers. Plaster of Paris is gypsum that has had the water driven off by heating and could also be used. Gypsum also supplies sulfur.

I usually mix gypsum with an equal amount of Epsom salts in a gallon of water.

[Leafmite]

I add eggshells (they take a while to begin decomposing) and in the summer, I add powdered milk to the water. I also use an MSU formula fertilizer now and then. Calcium is very important. I lost a bunch of my cattleyas and a few others one year due to calcium deficiency (leading to black rot).
Pond stores often carry fertilizer for lilies and lotus which contain high amounts of calcium. There are many ways to get calcium to your plants.

[Bud]

I pound to small pieces some oyster shells and add it to the mix....I also crush with my bare hands fresh egg shells into smaller size to add to my orchid mix....they are deterrent for snails and slugs too....

[TOMMYMIAMI]

I use MagiCal by rec. from one of the members here, and my Catts that has never bloomed before are blooming this year, some even second time!

[tucker85]

Don't be too worried about it. Most tap water contains calcium. If you use tap water to water your orchids they're probably getting enough calcium. If you use rain water or RO water, then you should look for a fertilizer that contains calcium or use a calcium/magnesium supplement.

[Orchid Whisperer]

Tucker, the Ca and Mg can vary quite a lot, depending on where you are and the geology beneath your feet. In Florida, you have a lot in your water almost everywhere. Here in northeast Georgia, we are pretty Ca and Mg deficient.

The good news is that if you are on city water, the water department should test the water supply and can probably provide test results if you ask.

[Polarizeme]

Be careful when adding Ca & Mg to your fertilizer. I've always watered with one or the other, but not at the same time (fertilizer and Ca Mg).