Alternate calcium source for plants

[DukeBoxer]

I've heard of using oyster shells now for a long time as a top dress for a calcuim source for paphs and mexipediums (maybe phrags too, but I'm not sure) but I was thinking to myself the other day...Why couldn't you use egg shells??? I'm sure that for some people they are easier to get a hold of than oyster shells and they do the same thing, break down over time releasing calcium into the substrate. I make a fermented tea called Kombucha that is very acidic (2.3 - 3 when finished) and I read also that you can add cleaned egg shells to it to bring up the ph. Anyone else have any ideas on this?

 

[bwester]

i used pelletized dolomitic lime. plants seem to love it

 

[NYEric]

Welcome from NYC!

 

[Rick]

I don't think its so much the calcium that the plants are after, but a buffering source to keep the potting mix pH from dropping too low. Egg shells are a pretty decent slow release Ca source, but a poor buffering material.

 

[practicallyostensible]

i used pelletized dolomitic lime. plants seem to love it

Now that's just clever. Where do you get it from?

 

[kentuckiense]

I imagine eggshell is fine as long as you wash it.

 

[biothanasis]

Wouldn't trimed bone of cuttlefish be ok for paphs? It is said to contain great amounts of Ca ...!!!!

 

[Rick]

Wouldn't trimed bone of cuttlefish be ok for paphs? It is said to contain great amounts of Ca ...!!!!

Its softer than oyster shell, so it may dissolve to fast if its ground too fine, but otherwise its the same as oyster shell in chemistry

 

[Ray]

I agree with Blake. Dolomitic lime - available in 50# bags at any lawn and garden store - is a good choice because it provides both calcium and magnesium.

Dolomite is also sold as a fish tank substrate for African cichlids, and has the advantage of being coarse chunks of "rock", as opposed to powder or pelletized granules (which are better than the powder), to kelp keep the medium open.

 

[CLMoss]

Hi All,

I must have forgotten that paphs may need a bit of extra calcium... Could that be the reason that some of my paphs have not bloomed in years?!!!

OK, you can get oyster shells (flaked) in just about any pet store. It is used as a source for calcium for small parrots. And it is cheap. I have a small container here (13.5 oz) that may have cost about $2.00. Also, the flakes look like they are the perfect size to add to any size media.

BTW (by the way), how much should you use to help these paphs get the proper amount of calcium? Just a sprinkle?

Thanks, Claudia