Hausermann's answer on tightly packed sphagnum moss

[MateoinLosAngeles]

Hey all,

Who doesn't love to revisit the topic of tightly packed sphagnum moss? I emailed Hausermann and they were kind enough to explain their process. Below a copy/paste of their email:

Hi, right. That’s how most nurseries including us, get their plants from Taiwan. They come in
tight compact moss. Then we just fill in around the edges if needing a bigger pot. We water those about every 10 to 14 days from the top.

Many of our customers, like interior designers/landscapers, garden centers and flowers shops simply
prefer moss because it’s a lot less watering/care.

If plants originate from us we generally grow in a bark mixture like the Bellina you mention.

For those curious my original email:

Hey there!

I've purchased a bunch of orchids from you in the past year, and they generally always arrive in good condition and healthy.

Something I've noticed from you and other nurseries is that your Phals are potted in what seems like extremely packed sphagnum moss or some other moss. When I repot your plants, I noticed at the core of the root ball I could see the shape of the older container, so my understanding is that once your young plants outgrow their 2-3" containers, you repot them in 4" pots without removing the old medium, just packing fresh moss around them. This would mean that you only repot your orchids once, and based on the life of an orchid from youth to adulthood, your oldest media might be 3-4 years old and about 2 years for the newer one.

The exception to this would be the Phal. Bellina, which came in what seemed to be fir bark. Yet it was really wet bark.

I live in very dry LA, and finding suitable media to grow orchids comfortably is challenging. You and other nurseries follow this very packed moss strategy. Given the proper watering schedule and greenhouse conditions, your orchids grow very well in your possession, with significant root growth and very little rot, if any. Most orchid enthusiasts also speak well of the quality of your orchids and the very good prices, making us come back over and over again.

Could you expand a little bit on your decision to pot Phalaenopsis in tight moss and how you manage your watering schedule, watering technique, and water amount per plant?

Some of the info I've found suggests the tightly packed moss actually retains less water, letting the roots breathe more easily while retaining moisture for longer. Of course, I wouldn't try to replicate your techniques in the home condition as my humidity, temperature, and light will be different. But understanding the logic behind your growing technique might be extremely helpful to me.

Thanks!

[Clawhammer]

I am a proponent of tightly packed moss for phals. I think I will find more allies on this board than Facebook, where I was recently sharply in the minority in extolling the virtues of tightly packed moss.

Hauserman is a great company.

[My Green Pets]

I have been trying to figure out how to get cattleyas to grow in moss. chadwick and christofferson both use it. from the photos i see, it looks like the rhizome is completely under the moss so that the roots emerge while already in the moss. it seems like if the roots emerge above the moss, they won't go down into it. or they'll go down till they touch it, then stop.

[Dimples]

Even though I have indoor conditions that are not unlike a managed greenhouse (with lower humidity) and could probably make sphagnum moss work for me, it’s not what I want in a medium. I use it in addition to bark for plants that like staying more damp/wet, but I dislike the way it dries when used solo. It stays wet/damp for a long time, juuuuust begins to dry then bam, it’s bone dry and a PITA to rewet without leaving it soggy. In my space, bark is ideal. I can water it whenever I want and drying is more linear and predictable. If I ever get something that wants/needs soggy, swamp-like conditions, moss sitting in a shallow dish of water will be perfect.

[Clawhammer]

Originally Posted by Dimples

Even though I have indoor conditions that are not unlike a managed greenhouse (with lower humidity) and could probably make sphagnum moss work for me, it’s not what I want in a medium. I use it in addition to bark for plants that like staying more damp/wet, but I dislike the way it dries when used solo. It stays wet/damp for a long time, juuuuust begins to dry then bam, it’s bone dry and a PITA to rewet without leaving it soggy. In my space, bark is ideal. I can water it whenever I want and drying is more linear and predictable. If I ever get something that wants/needs soggy, swamp-like conditions, moss sitting in a shallow dish of water will be perfect.

I find the tighter it is packed, the more uniform the moisture/wicking, and the more predictable/linear the drying. I feel like I have a much better understanding of the moisture content in the middle of the pot, based on weight of the pot and consistency of wetness, with sphag as opposed to other media. I always use it with a terra cotta pot, and often with underneath heating.

[MateoinLosAngeles]

Originally Posted by Clawhammer

I find the tighter it is packed, the more uniform the moisture/wicking.

I started to pack my moss around the roots while leaving a "ball" of bark, charcoal, and perlite in the center of the pot, letting the stem sit on it. I water from below and let the sphagnum wick up. During summer in my dry climate watering from above and in big quantities (a half gallon drench per plant) still required weekly or twice a week watering.

Now, the reason why I started to keep the coarse mixture in the center was due to a past issue with stem rot. However, I've been hearing folks packing in tight sphagnum mentioning they can better control the moist uniformity of the medium. I've also heard other people suggesting to blend some coarse bark with the sphagnum and instead of layering just creating a uniform tight consistency, letting the bark "help" you not to overtighten...

I've been playing with different setups and so far I have to say semi hydroponics has worked great with Phals. Whereas my bark+sphagnum mixes have had mixed results. I've never had success growing in pure sphagnum but I wonder if I didn't pack it enough, or I packed it too much...

[Clawhammer]

I have had poor results with bark / sphag mixes, they retain a lot of water and take a long time to dry for me. Loose sphag in the mix holds multiple times its weight in water vs compressed sphag. Leads to the bark breaking down much quicker in my experience

[estación seca]

Yes. I heard a long lecture on growing in sphagnum. Tight packing is very important.

[Dusty Ol' Man]

I'm afraid I'm going to agree with Dimples on this one. I received a plant in tight packed sphag from a private grower. He took the time to explain his watering technique which I followed to the letter. After awhile of showing new growth the plant suddenly stalled. When I pulled it apart to check the roots I found the middle of the moss dry as a bone while the outer edges were still slightly moist. All the roots were dried out. If a grower has a handle on growing in moss, I say go for it. I'll stick to other media and methods. I grow few, select plants and any losses are big losses.

[Clawhammer]

Originally Posted by Dusty Ol' Man

I'm afraid I'm going to agree with Dimples on this one. I received a plant in tight packed sphag from a private grower. He took the time to explain his watering technique which I followed to the letter. After awhile of showing new growth the plant suddenly stalled. When I pulled it apart to check the roots I found the middle of the moss dry as a bone while the outer edges were still slightly moist. All the roots were dried out. If a grower has a handle on growing in moss, I say go for it. I'll stick to other media and methods. I grow few, select plants and any losses are big losses.

I don't understand how it is hydrodynamically possible for the middle to be bone dry while the outside is still moist.