Sphag - how wet is too wet?

[ldaniels]

I've recently potted up some cattleya and dendrobium seedlings from both compots and a flask.

I layered their pots with a few styrofoam peanuts first, then some cattleya mix and finally sphag.

My question is about the sphag...I always seem to cause rot with this stuff!!! Obviously I've kept it too wet in the past. So how does this stuff work?

Do you let it dry out completely before you water/spray it? do you spray to keep it at a constant "just wet" feel?

Help!? please

[Bill U.]

I normally avoid sphag anywhere near my catts. I just find that it stays too wet for my conditions. But I think when using it as a topping to help keep things relatively moist, that you should be keeping it just barely damp and letting almost dry out.

I am not entirely sure, but I do know that while they are still seedlings, you don't want to keep things too damp. Maybe try using the skewer method for the centers? That way you can tell if the center is staying really damp or wet and hopefully tailor things to dry up before any rot sets in?

[ldaniels]

oh great idea, Bill U! I need to find some skewers

[kindrag23]

I use it here in Texas because this time of year its usually hotter then hot so it helps me out by staying a little wetter than bark or lava rock. In the winter I dont water very much if at all with my plants so it works out for me as well. I would definitely use the skewer method it will be good since these guys are small and you dont want them rotting. Good luck on your flask babies!

[MrHappyRotter]

I'm not trying to ask a stupid question here, but if you know you have problems with sphag and plants potted with sphag in your care are prone to rot, then why are you even using it in your mix?

There are some reasons someone would use it in their mix. First, it's moisture retentive, so it's good for dry climates, for people who can't or don't water much, and for plants that need to stay hydrated at all times. Second, it's acidic, so it helps keep the pH around the roots lower. Third, in some places, it's cheap and more readily available than more appropriate constituents.

I obviously don't know your situation, but I don't really think any of those cases apply. So, I guess what I'm saying is, unless you've got a good reason to use sphag, and knowing that it doesn't work well in your growing environment, maybe consider not using it.

[ldaniels]

kindrag23- I wish I had the humidity you have in TX!

MrHappyRotter - not a stupid question at all I should have posted that the reason I went with the sphag (even though my history with it is horrible) is because this is my first venture with seedlings and from everything I've read and all the postings I've found, sphag seemed to be the best way to go to help the little ones along.

This is really the only reason I'm using it! I'm able to tend to them every day, so it isn't a matter of not being able to water them. The climate here is dry but I'm keeping these indoors, so it's not for the humidity/dryness factor.

I really just thought that the moistness would help nurture their little roots to grow! Maybe once I see their roots starting to take off, I'll remove the sphag on the top and replace with more cattleya mixture medium.

[lilol]

I don't like sphag in pots. Only on mounts.

[WhiteRabbit]

I don't do tiny seedlings (because it's hard for me to get the watering right; they don't leave any room for error) - but I do always use skewers to judge media moistness. I thinks the tiny babies should be nearly dry before watering, but not allowed to sit dry for long.

[Leafmite]

I've grown a few tiny seedlings in the past with success by using plastic Vanda baskets with a layer of NZ sphagnum moss. I kept the moss moist but there was plenty of air to the roots to prevent rotting. That is just one way to grow those tiny seedlings....
As for the other orchids, I use moss for some of the orchids that need more moisture but usually as a top layer with the bottom being red lava rock and, always, in a net/basket pot. The only exception are mounts and the bulbo (a shallow pan with a two inch layer of moss).

[james mickelso]

Instead of a top layer of moss I would shred the moss into small lengths and mix it in with the other media. Placing a layer on top won't really keep the media underneath as damp as you might think. Using it as part of the media will keep it damp all the way through the entire pot and if the media is coarse enough, the media will all dry out roughly at the same time. After learning to used moss correctly I have come to use it more and more with good results. The drier your environment, the more moss you use in your mix. The wetter your environment, the less you use. I now use it on certain cattleya. Most all of my phals have at least some moss in the mix or straight moss on around half of them. Remember that seedlings have no room for error. they have no reserves of moisture. So hydration is paramount. I would even go so far as to put some systemic fungicide/bactericide in the water you use once a month to stop any infection before it starts.