Need some guidance with watering dendrobium

[jomtos]

Hi all

I've been looking for information about how to water dendrobium. For example with Phals the color of the roots will tell you when you need to water or the leaves (but this one is too extreme or maybe even dehydration but you get the point. ) or when they had enough but with dens i cannot find that kind of information yet.

Photos for reference.

[aliceinwl]

Watering depends on the type of Dendrobium. If yours is a Dendrobium phalaenopsis type, I try to water mine whenever the substrate approaches dryness without letting it dry out completely.

[Ray]

They key to watering orchids is to make sure the roots have plenty of AIR along with water. If that thing is potted entirely in those granite pebbles, you can probably water frequently with impunity.

[SouthPark]

Originally Posted by jomtos

For example with Phals the color of the roots will tell you when you need to water or the leaves (but this one is too extreme or maybe even dehydration but you get the point. ) or when they had enough

Hi there jomtos. One thing to think about here is ----- colour of roots doesn't necessarily tell us when we should water the orchid. This is regardless of whether we can see the surface roots and cannot see roots embedded underneath the surface of the growing media.

As you're using regular rocks for growing your orchid - which is actually ok ------ ie. just need to have a workable watering schedule --- then just make sure your pot has very good drainage holes at the bottom, dump lots of water through that rocks media every morning ---- and (if you want) every evening too. Regular rocks won't be holding water anywhere near as well as say scoria rock. But at least - for regular rocks (that you're using) - it's generally ok to dump water into there as much as you want.

Just make sure you have good air-movement around the plant ----- avoid still-air environments.

[jomtos]

Thank you so much for all the answers.

They came in rocks so I'm gonna leave them in rocks.

I used phals as example since looking at the roots you can tell whether they need water or not( if you're using clear pot). I thought with dens you could do the same.

I just don't wanna kill them by overwatering.

[SouthPark]

Most welcome jomtos. I've stayed away from clear pots, as they tend to allow light in, which then seems to promote algae growth, which then leads to other things.

I reckon that 'overwatering' is a term that should be associated only with the growing media and environment condition inside the pot. This is for cases where we just have a pot and media like rocks, scoria, leca or something.

If the growing media is a kind that can become saturated with water for 'some period of time' (which can sometimes also be linked to poor drainage of a particular pot having not enough draining holes), and the water trapped in the media is unable to move much or at all, then water can stagnate inside the pot ---- stagnate around the roots - oxygen/air content becomes low. If this happens, roots don't get the air or oxygen that they require to survive - and those roots can then degrade and rot ----- preventing the plant from getting water into it.

So - to avoid issues with roots (and plant) ----- ensure:

1. Good air-movement (around leaves, stem, roots, media), which usually allows satisfactory water movement (and hence oxygen in the water to move and get constantly supplied to the roots) if the chosen media and chosen pot allows for it. Avoid still air environment.

2. A pot that has good drainage holes.

3. A 'suitable' growing media is used that allows the grower to keep to a particular watering schedule (including amount of water to apply during each watering).

4. Knowing how much water should (or can be) applied for a particular workable growing media and/or pot-media setup.

[jomtos]

@southpark

Thank you for always taking your time to help others. I'm always learning from your posts.

I'll try my best to maintain those conditions.

[Roberta]

Originally Posted by jomtos

They came in rocks so I'm gonna leave them in rocks.


I just don't wanna kill them by overwatering.

That's the great thing about rocks ... pretty impossible to overwater, since there's no water retention, just surface area that gets wet and then dries. The roots are getting "humid air" which is what they want.

[jomtos]

Originally Posted by Roberta

That's the great thing about rocks ... pretty impossible to overwater, since there's no water retention, just surface area that gets wet and then dries. The roots are getting "humid air" which is what they want.

Here in DR almost 95% of the time when you buy a Dendrobium they come in rocks, phals in coconut husk or tightly moss (bad quality). Vandas in hanging basket. Cattleya in moss and so on.