Potting Medium Experiments

Is anyone using home-made media?

I have noticed in my last sack of "big-brand" orchid potting medium that there were rocks and other ingredients that looked to me like the sweepings of the warehouse floor.

I know we use all kinds of non-soil potting media, such as those terra-cotta beads, but this felt to me like that company is taking advantage of us.

It also caused me to think a lot about the commercial bark media. So much of that looks like nothing more than smaller bits of the same bark that is used as mulch to discourage weeds that I decided to experiment a little.

I did have one of those pine trees that likes to shed flakes of bark in my yard at my old place, and it only took about ten minutes to gather a nice quart-size plastic sack-full. I crumbled that up and mixed it with some bits of charcoal and some of the store-bought mix, and those orchids definitely took off. Not a scientific sample, to be sure, but encouraging. I have to believe that the freshly-gathered bark has more nutrients natural to epiphytes than the ground-up processed bark flakes.

Now I have different pine trees available. These don't shed bark as nicely but they are a good source of dry twigs and needles. I gathered some of the needles and crushed them up by hand and am using them instead of coconut fibers for my flasklings. So far they look ok, but they have been in it only about two weeks.

The goal of mixing personalized orchid media is not for the purpose of nutrition for the plants.
Any of the materials used for orchid mixes are either inert or decompose at such a slow rate that they provide negligible nutrients to the plants. The primary source of nutrition for the plants will be from the sun and water, and supplemental fertilizers.

The main factors that are being controlled with these personalized potting mixes are moisture retention and air flow.
Some orchids prefer to stay moist all the time, requiring a mixture that retains water for a long time. Some orchids prefer to dry out quickly, requiring coarse potting media with plenty of air passages. And then there are a lot of orchids that prefer conditions in between the first two.
That, in combination with the grower's personal approach to watering/feeding schedules and local growing conditions, lends to quite a myriad of personalized orchid potting mixes.

The "all-in-one" mixes offered at general stores are a shotgun approach, intended to cover as much of the plants and growing conditions as possible. They may not be the best for your specific combination, but it is a sure bet that it gets the job done for majority of the growers if they choose it.

As you gain more familiarity with your specific orchids and what they want, you can then tailor your own personalized potting mix to achieve the best root zone for your individual plants. Get individual bags of homogenous potting mixes and create your own mix. If you have access to backyard potting supplies, then even better.

Nice post, John! I would only add that mixing your own medium over the store bagged versions can be fun. You get to tailor your mix to you own situation and it gives you the pleasure of knowing you have been successful in creating an environment where your orchid can thrive.

Cheers,
BD

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We could learn a lot from crayons: some are sharp, some are pretty, some are dull, some have weird names, and all are different colors....but they all exist very nicely in the same box. ...Hmmm? .

The medium you use can help you to give your orchids better care, too. I switched to those clay pellots and clear plastic pots (S/H system) because I am an overwaterer. Being able to see the moisture level in each pot has helped me control the urge to give the plants water. Now I can wait until they are dry, Knowing they haven't been dry too long. This is really helping my catts and phals. You can see that there are several factors to consider when choosing a medium for your plants. Have fun expirementing!

Here in florida the palm tree leavings, cut to size, do a fine job as well. They have this stringy stuff where branches have come off, under the leaves that works great. The dried out seed pods are great for mounting as well. Their wood is ridged and plants grab on fast. Again you cut them in sections the size you want. Screws go into all palm wood easily for hanging. You just soak the wood in a bug and fungus killer.
Connie

I have been an over-waterer, too, and I never thought of the fact that clear potting can help.... du-uh....

Connie-Jo, those seed-pod mountings sound interesting. You ought to consider putting some in auction for people who don't have access to that type of palm tree...

how do you guys all feel about coco coir? i've been using the pith for the veggies (basically in place of peat, mixed into the soil and pots along with compost...) and i love it... i've heard it's good for orchids but that's always from people selling it...
i wanted to switch my african violets to it but a bunch of people on my av board warned me off it for them, so i'm worried it'd hold too much water for orchids... thoughts?
i use a 'big brand' mix now and am not too pleased with it, actually i've tried three brands so far and had many issues. one didn't hold any water almost, the next was fine for the phals but seemed to get stuck to the catt roots (and there's still little bits on them cuz i absolutely could not get them off...) and the one i'm on now is ok but it's a lot of big peices and isn't doing a lot to hold the orchids in the pot...
otherwise d'you think those expanded clay pellets for hydro would work without a hydro system?

I think the clay pellots could be made to work with a non-hydro system. Probably be easier to go to the semi-hydro method, though. You soak the pellots overnight before using them. Hmmm! To water without the semi-hydro reservoir, maybe soak pot and all in a bucket of water/fertilizer for 10 minutes, then drain.Might have to "water" a couple of times a week. With the semi-hydro, I am watering about every 10 or 12 days for my catts, maybe every 7or 8 with the phals.

My vanda seedlings are set up in small pots with the LECA pellets without a reservoir. I water heavily once a week, and the misters take care of the humidity in between.

The vandas set up this way are performing much better than those that are naked (just plastic basket with nothing else) and those in small bark.
Cattleyas and hard cane dendrobiums should do well in this set up as well, as long as there is adequate humidity in between waterings.

I have quite a few Catts. in just the pellets not s/h the only thing I have found is the pellets will pick up heat when in the sun , also have a couple of Vandas in them .
I have been buying straight Orchid bark from a warehouse then mixing sponge rock and Hort. charcoal in it if desperate I get a bag of mix from a box store and mix it into the straight bark .
Cypress mulch works for Phals and others but is light have to put rocks in the bottom of the pot, have one plant in wine corks , Also used large landscape bark for Vandas it did not fall apart like the regular bark . Gin

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