Adding Chalk to Paph mix for lime needs

[kaarthiik]

Hi Guys,

I would like to know if we can cad add Chalk to Paphs as supplement for lime ? Just got the idea that Chalk is a form of limestone.

In my area, I cannot get a horticulture grade lime to add, I had to import but it would take time.

For now I am adding some Egg shell powder (done by me).I add a pinch to two for a plant of BS (not big plants, medium) Is this enough?
I use MSU as fertilizer at 70 PPM N - 3 to 4 times a week.

Please also suggest any other easily available supplements for lime.


Thanks,
Kaarthiik

[WhiteRabbit]

[Paphluvr]

As this article from Wikipedia states, it depends on what you mean by chalk. Natural chalk should work.

Chalk - Wikipedia, the free encyclopedia

[Ray]

If you are using the 13%N MSU formula, at 70 ppm N 3-4x/week, you are providing plenty of calcium and magnesium already.

[katrina]

I might be wrong here but it seems to me that when paphs grow on limestone (in nature) they are getting very, very minute amounts of the limestone (and all associated properties of the rock) over a long period of time but putting chalk in the mix might give them a higher dose of whatever is in that rock and at a faster rate that what they would get just growing on the rock. Maybe?

In the US most aquarium stores have Limestone for tank set ups...is that something that you might be able to find locally? You could get some smaller pieces and put some in the pot (or break some up to put in the mix) w/your paph medium...it would add weight to the pot and I would think it would be more naturalistic in break down vs adding chalk. Maybe? Just a thought.

BTW...not all paphs are going to appreciated added lime or cal-mag. As a matter of fact, some won't do well at all in the higher PH condition created by the addition of limestone.

[kaarthiik]

Thanks a lot for all your replies.

I meant natural chalk, I felt that my paphs are getting lesser limestone supply as I have seen slow growth, adding egg powder I felt something improved.

And when I checked my old medium (all stone mix) of concolor - pot broken, I seen many white pebbles (50% to 60% media) when scratched I felt it was like chalk so got the idea of chalk.

I tried local aquarium stores, they dnt have lime.. Need to search, I feel it is easier to import oyster shells.

[hagfish]

You may be growing your concolor like I grow my niveum. I think both are in the brachypetalum group and are small, thick leaved plants adapted to higher light. The source of my lime is ordinary limestone gravel. Niveum supposedly grows on old limestone outcrops yards from the sea and many of these may be ancient coral deposits. As noted, coral chunks are available in aquarium shops. Larger pieces can simply be broken up into chunks under an inch in size. I mix limestone and humus and it suits my plant just fine. Since they are so exposed and grow in rock cracks, I think they must get lots of air movement around the roots. I have my plant in a small plastic container in which I have melted a series of holes. Chalk is lime powder and probably won't facilitate the porosity of the medium as well as something chunky could. I've had concolor before but I can't remember what I had it potted in.

[NYCorchidman]

I agree with what Katrina said.

While many paphiopedilum species live on rock outcrops, that doesn't mean they need tons of Ca and Mg. Even the categorizing paph according to their preference of acidic or basic substrate is actually misleading. That was not based on the observation of their culture, but rather based on the pH of the substrate they were found growing on, then added note on habitat condition, which many of them include limestone outcrops. hence the wide spread notion of adding extra lime on the mix.

If you are already fertilizing them with well balanced fertilizer containing enough Ca and Mg, and the pH of your potting mix is not on either extreme, then you should not worry.

I would say anything between pH 6.5-7.2 (approximate) should work for any plants including orchids regardless of their "preference" if that really exist, with of course the exceptions of odd examples of plants that really do need certain extreme pH to grow properly.

None of the paphiopedilums fall under any of that exception.

Too much and too little of lime may adversely affect plants as a result of interaction with fertilizers. hence the above mentioned pH range for pretty much any plant is safe.

[kaarthiik]

Thank you all..

I learnt nice things, and my worry of Ca is reduced.. NYCrochidman.. Thanks again.

I have Niveum too.. hagfish.. I think I was giving bit lesser light.. I would elevate the pots. Might it could be the reason.

I have concolor in humus and some limestone pebbles .. I have niveum in sphag moss and clay pieces with egg shell powder added. It seems I am giving bit lesser lights to these Paphs.. will elevate them to little more light and would post the results.

OB has wonderful and helpful people

Cheers,
Kaarthiik