Questions about my watering and fertilizing schedule.

[Hamlet]

Hello dear slipper experts,

I didn't know whether to post this in the newbie section or here, but as it is more of a general culture question, I decided to post it here.

I've read a lot about watering and fertilizing, but it still remains the most problematic aspect of orchid culture to me. Here is how I currently water and fertilize my slippers:


Phragmipedium:

Watering: RO water mixed with tap water, between 30-60 μS, I keep my Phrags wet and water them every two to three days, when it's hot in the summer, daily.

Fertilizing: RO water mixed with fertilizer up to 100 μS every other or every third watering, usually about once, sometimes twice a week.

All my Phrags stand in about 1/2 inch/1cm of water, with the exception of popowii, which does not stand in water and which I only water when the medium starts to dry. Same schedule all year.


Paphiopedilum:

Watering: I treat these like my Phalaenopsis: RO water mixed with tap water, between 100-150 μS. I water when the medium starts to dry, about two to four times a week. I keep the medium moist, but not wet.

Fertilizing: RO water mixed with fertilizer, between 250-300 μS, every other watering, so once or twice a week.

I have mostly Parvisepalum and Sigmapetalum alliance Paphs. Seedlings and mature plants are treated the same.

• Am I correct in assuming that Paphs have no winter rest, so I can use the same schedule all year? One species I am not sure about is micranthum. I have read conflicting info, some say this species needs a dry winter rest with reduced watering and no fertilizer and others say it doesn't. Which should I believe?
  
  
• Some weeks when I am very busy, some of my Paphs get quite dry or the medium almost dries out completely before I get to water them. Does this hurt the plants?
  
  
• I switch back and forth between two fertilizers: NPK 17-7-8 and NPK 20-5-10. Are these suitable for slippers?
  
  
• Is my watering and fertilizing schedule fine, what could I improve, or what am I doing wrong?

I am sorry for all the questions, but I promise that I have used the search function extensively. Still, I am unsure if my methods are the right ones.

Thank you in advance for any replies.

 

[NYEric]

Some Paphs prefer cooler/drier winter to initiate blooming. It is better not to let the roots dry out. Questions about fertilizing here can get you shot!

 

[Justin]

it all sounds good. Paphs can dry out occasionally with no problem, but if they get bone dry too frequently you will have problems. Maybe add moss to the mix to retain more moisture.

 

[Erythrone]

IMO, many Phrags are heavy feeder compared to Paphs. Most of mine are now fed with 300 μS/cm with each watering, and I water several times a week. And I grew some plants with much more fertilizer for years (Grande, Jason Fischer, Autumn Fire, Evening Blaze).

But some dislike it (popowii, fischeri, besseae flavum, some fischeri hybrids. Hanne Popow). I fertilize them with a solution wich is less than 80 μS/cm

 

[troy]

I give phals 1/4 of the fertilizer that paphs receive other wise the roots burn and keep the ph at 6.5 no higher alot of paphs are rock dwellers

 

[Stone]

I would just say that you can't treat all Paphs as one group. For example, a P lowii is as different to a P micranthum as a Cattleya is to a Masdevallia.
I think it is especially important to distiguish between the ''island'' species and the ''continental'' species when it comes to watering. That is the first group are very seasonal and the second are not.

 

[Brabantia]

I give phals 1/4 of the fertilizer that paphs receive

Is it not the contrary?

 

[Hamlet]

Thanks for the replies.

IMO, many Phrags are heavy feeder compared to Paphs. Most of mine are now fed with 300 μS/cm with each watering, and I water several times a week. And I grew some plants with much more fertilizer for years (Grande, Jason Fischer, Autumn Fire, Evening Blaze).

But some dislike it (popowii, fischeri, besseae flavum, some fischeri hybrids. Hanne Popow). I fertilize them with a solution wich is less than 80 μS/cm

That's interesting, I always read that you should be very careful to not over-fertilize Phrags as they are very sensitive to salts and the leaves get brown easily from fertilizer or water that is not pure enough. My vendor said the same. But I only have Hanne Popow, schlimii, besseae, kovachii x schlimii and popowii, most of which you said dislike heavy feeding, so confusion averted for now. =)

I would just say that you can't treat all Paphs as one group. For example, a P lowii is as different to a P micranthum as a Cattleya is to a Masdevallia.
I think it is especially important to distiguish between the ''island'' species and the ''continental'' species when it comes to watering. That is the first group are very seasonal and the second are not.

Thanks for the tip, though reading through the data sheets on slipperorchids.info (seems to be the most comprehensive source I could find on this topic, are there others?) it seems that continental Paphs from China and Vietnam (basically all Parvis) have more pronounced dry periods in the winter months than those from islands like the Philippines? I guess I should be extra careful to not overwater during the winter and keep Parvis like micranthum a little drier? I have micranthum albescens and eburneum and I really don't want to kill them and try to get them to flower, and from what I read a winter rest is needed to initiate spiking. The albescens form seems hard to find so I want the one I have to survive and thrive.

It's very interesting to hear different imput and how other growers water and fertilize, but the more I read the more confusing and complex it gets! Phrags seem to be the most straightforward so far, it's hard to overwater plants that like to be wet always.

 

[Stone]

Thanks for the replies.



That's interesting, I always read that you should be very careful to not over-fertilize Phrags as they are very sensitive to salts and the leaves get brown easily from fertilizer or water that is not pure enough. My vendor said the same. But I only have Hanne Popow, schlimii, besseae, kovachii x schlimii and popowii, most of which you said dislike heavy feeding, so confusion averted for now. =)



Thanks for the tip, though reading through the data sheets on slipperorchids.info (seems to be the most comprehensive source I could find on this topic, are there others?) it seems that continental Paphs from China and Vietnam (basically all Parvis) have more pronounced dry periods in the winter months than those from islands like the Philippines? I guess I should be extra careful to not overwater during the winter and keep Parvis like micranthum a little drier? I have micranthum albescens and eburneum and I really don't want to kill them and try to get them to flower, and from what I read a winter rest is needed to initiate spiking. The albescens form seems hard to find so I want the one I have to survive and thrive.

It's very interesting to hear different imput and how other growers water and fertilize, but the more I read the more confusing and complex it gets! Phrags seem to be the most straightforward so far, it's hard to overwater plants that like to be wet always.

I have read that armeniacum, emersonii and delenatii do not like to dry out even in winter. ( there may be others ) Experience is always the best teacher. Specific info is always hard to find. I agree it gets confusing but as always you have to learn everything you can about a particular subject before you can ''forget the rules'' and experiment. If you do it the other way round you will fail
I got a flask of eburneum about a year ago. They really struggled for a while but now they are booming. What have I done differently? I don't really know. Maybe kept them a bit wetter?

 

[Stone]

But some dislike it (popowii, fischeri, besseae flavum, some fischeri hybrids. Hanne Popow). I fertilize them with a solution wich is less than 80 μS/cm

80uS/cm I think is 0.08 dS/m? If thats right, its almost nothing at all! Even my pure rainwater has a higher EC. I can't believe that these species can't handle at least 0.3 dS/m

 

[Erythrone]

80uS/cm I think is 0.08 dS/m? If thats right, its almost nothing at all! Even my pure rainwater has a higher EC. I can't believe that these species can't handle at least 0.3 dS/m

Under my conditions, in Summer, they don't like fertilizer at all.