suitable medium for Onc tsiku marguerite

[Fran20]

Just curious-- would using small lava rock exclusively be a suitable medium for a blooming size Onc tsiku marguerite? Or would it damage the relatively thin roots?

[Leafmite]

When I had a collection of large Oncidiums many years ago, I grew them in red lava rock and they did great. The trick is that when the visible roots turn white, wait a day or two, then soak them until the roots have once more become green.

I just bought a little Oncidiium Twinkle and I plan to move it to small lava rock this spring/summer.

[Fran20]

Thanks for the info!

[lolaebola1]

Hi My name is Teri and have a question about using a lava rock for my Onc Tsiku. How to you attach the roots to the rock? I have seen videos using a type of glue but that doesn't sound right to me. Any help is appreciated.

[fishmom]

Welcome, lolaebola1! I'm not sure just what you are asking. Are you planning to mount your Onc. on a large lava rock? Or are you using smaller pieces of rock as a planting medium in a pot ? Either way, the roots will attach themselves as they grow. In a pot, no attachment is required as the roots will work their way into the spaces between the rocks. If you are mounting, there are many ways other than glue to hold a plant in place; using monofilament or panty hose material are some that are popular. A search for mounting methods will give you more ideas.

[SouthPark]

I also grow my Oncidium orchids in lava rock (aka scoria). If it turns out that the oncidium hasn't got enough roots for getting firmly anchored to the scoria media, then you can always use a wooden skewer placed into the scoria, and use a plant garden tying strip (or anything else that works for tying) to gently couple the plant to the wooden skewer. This can be done until some of the roots do their natural thing - which is to eventually attach themselves to the rock. It takes time for this to occur. When enough roots become naturally attached to the rock, you can then either choose to remove the skewer/tie, or just leave the skewer/tie in place (ie. you can remove at any time).

Damage to roots can always naturally occur. We always try to minimise or avoid damage. But even if there is some damage, then the damaged regions will generally seal up by themselves.

[Roberta]

Potential root damage from handling, along with the fact that they tend to be specific to their medium, both are major factors behind the "pot when you see new growth/roots" advice. When the plant is actively rooting losing one or two isn't going to matter much. And the new roots will make themselves at home in the new medium. When mounting, that's even mroe important ... older roots will keep the plant hydrated, but only the new ones will grab a mount. If potting, the old roots have a better chance of keeping the plant hydrated while the new ones are growing, and they help to anchor the plant in place. It is super-important to make sure any newly potted or mounted plant is held firmly in place - any movement (like from wind) can cause the delicate hairs on the growing root tips to be damaged and stop growing. So don't be shy about staking (or firmly tying a mounted plant)