Feeding the Masdies
 

Since many years I search on the Net what is a good regime for feeding the Masdevallia.
I read the most various opinions and often very diverging.
This last in date from a renowned producer (on its site):
"Fertilizer: as with most orchids the mantra is “weekly, weakly”. We fertilize once a week at a low rate of 100 parts per million nitrogen".
Is that a low rate ??
If the maths are correct this mean 750 to 850 ppm of total salts (in function of the percentage of Nitrogen in the fertilyser). It seems to me a little bit high :).
On Wiki I read: They should be fertilized with a half-strength mixture of a balanced fertilizer once a month and a high nitrogen fertilizer can be used for single applications in the spring and fall.
How high is a full strengh ??
Here in Belgium a nursery recommend 65 ppm N from a 13_3_15 Ca Mg one time per week. I have tested ... roots burn!
So in touch with your experience can you recommend me a level of feeding and a frequency which would be completely allowable to feed Masdevallia without the risk of burning roots or seeing appearing black stains on leaves. Thank you in advance.

That does seem high to me, too. I only have a couple of Masdies, and am still working out the fertilizer, but what I have mostly read here seems to be about 1/4 strength (of more typical "feeders", I guess).

Hopefully more experienced Masdie growers will chime in.

Apparently I have sixty-four of them now. Just came home with a couple today and decided to count.

Anyway they are super light feeders. I use K-lite (12-1-1-10Ca-3Mg) like I do on all my other orchids. I do it once every two weeks or so, at about 60ppm.

I also foliar feed them KelpMax every two/three weeks (separately) and feel like this is an awesome thing for them. I've pulled plants out of their pots after having them for a few months under this regimen and can see the difference right in front of me with root quality.

Note - I have two mounted Masdies, and probably six or so that are still left in bark from when I bought them, but all the rest are in premium NZ Sphag in clay pots.

I only have one Masd and when I first had it I fed it too much. It got 3 spindly flowers. Last spring after reading that some people use slow release fertilizer, I put just a little around the plant. It looks very healthy but hasn't bloomed yet, so I'm not sure of the results.
This one is Andean Prince. I'm not sure that it is a good bloomer.

I feed every other week 1/2 strength year round. In the winter the feedings are spread out a little more due to the humidity and the moisture retention from the cooler temperatures.
I'm trying some slow release on some of the plants to see how they fare.

I put a little slow release on mine last year and it grew well but still hasn't bloomed. I don't know if it is just the particular masdie I have, but I haven't been too pleased with it. It hasn't bloomed well. I also have to constantly watch for scale.

I've had good luck with masdies although I had to give them to a friend with a greenhouse to foster for me when I moved to being a snowbird in Costa Rica and couldn't ask my sons to care for them over the winter. I fertilized 1/2 strength every other week or 1/4 strength weekly.

Thank you all for your responses. But ... for me when you speak strength for a fertilyser that say nothing for me if you are not saying me how many is the full strenght and which fertilyser you use. For me a 13/3/15 (or other)
at a concentration of 0.5 gr/L it is more eloquent.

It's impossible for everyone to do the math for each other, as so many products are different.

Here, you can use Ray's calculator to determine what works for you:

Fertilizer PPM Calculator

I don't have any masdevallias. I have many cattleya, and various phalaenopsis, paphiopedilum etc. I use RO water with added nutrients at every watering. The concentration of added nutrients is usually in the range of 100 ppm to 300 ppm. 100 ppm equals 0.1 gram per liter.