18-18-18 FERTILIZER PROPER USE

[lemonchan]

well.... i recently bought a reallllyyy goood fertilizer... but... im afraid to use it wrong.

its called KRISTALON... its not american.... (because... im not american...)

its 18-18-18-3

and i got.... a masdevallia vetichana

a cattleya rex

an encyclia who is about to die...a cymbidium who was recently repotted as well... and many epidendrums

every what time should i use the fertilizer and what ratio should i use.

[Donald]

I am baffled as to what the last number (3) signifys.

[Pilot]

Me, too...I don't know what the last number is. Lemonchan, don't take my advice as THE way to do this but when it comes to fertilizing orchids, go weak. At 18 across the board, I would use no more than 1/4th of the recommended dose per the manufacturers instructions. In fact, you may want to go even weaker at first and gradually up it to 1/4th the strength.

I personally use a liquid fish fertilizer that is already half-strength by comparison to stronger fertilizers (such as 16-59-16 that I use for my heavy flowering or fruiting plants like my apple trees, plumeria etc that require loads of phosphates). By using a weak fertilizer I can cut it in half and not worry about burning the plant.

I'm brand new to orchids myself so please take my suggestions with a grain of salt. But you have to remember that your orchid should also be in a medium that is quickly and freely draining-- so really, if you do fertilize and water the plant it shouldn't be sitting in water full of fertilizer. Plus, if you pay close attention to the medium, such as the bark, if you are putting too much in, you'll see the salt appear on the bark (this is how I watch the fertilizer level for some of my amaryllis bulbs). If salt appears or there is crusty white stuff forming on the bark, flush it with clean water.

[camille1585]

The 3 is for magnesium, it's the fourth 'major' element and plants need it for blooming. I know that in France it is common to see it on the labels of commercial fertilizer formulations. If you look, many fertilizers we use don't have Mg mentioned on the label (I use Pokon orchid fert, and there's no Mg)
'Weakly weekly' is the best way to fertilize, meaning that you should fertilize every watering, and water with clear water every 4-5 waterings to leach slat build ups in the pots. For most orchids you want to shoot for about 125ppm N each watering, so with this fertilizer you need to add about half a teaspoon per gallon.

For the masdie you need to give much less than that, as they don't tolerate salts very well. A friend on OB gave me advice from a masdie grower. Water frequently with pure water, and fertilize about once a month at 80-100ppm N. With your fert that would be a bit less than half a teaspoon per gallon

[rogerman]

I use 21-21-21-te. "te" stands for trace elements. I fertilize once a week at the ratio of 1 tablespoon per four gallons of fresh water.
I have no problems whatsoever with burning of leaves and the plants are doing extremely well.

[lemonchan]

3 corresponds to trace elements

[camille1585]

Originally Posted by lemonchan

3 corresponds to trace elements

Are you sure? To double check what I wrote, I just dug out my old lecture notes from fert management classes, and found that the 4th number (when there) is magnesium, just like I originally wrote in my post. Unless this only applies to France...

[learning2letgo]

Wow! Camille, you are chock of full of useful information! Quite informative, you are my dear...

[lemonchan]

thanks camille, it may work for some fertilizers... but the last number is stated as trace elements XD thanks for the info tho!