Switching to Semi-Hydro: a repotting pictorial

[Paphraguy]

Yes, most Phrag species like to be wet, so much that in nature they are at times completely submerged underwater in clean running water and not stale dirty standing water. The ones that don't like to be wet and soggy are the long petalled species.

[LJA]

One thing - the pot in the pictures shows holes all around. Unless you want to get soaked put holes only in one side. That way you can place the pot on a tray and catch the overflow.

That's exactly what I was going to say!

dosal, Sue, I'm sorry. I must be missing something.

The more holes you have drilled in the pot, the less water pressure you'll have at each hole when you water. If you put holes on only one side, each of those holes is going to spurt like a geyser when you fill up the pot with liquid.

With more holes all around, the excess water will be distributed evenly to all of them, resulting in less of a spray per hole, and a mess that's much more catchable in a drip pan if you're doing this indoors on fine furniture.

If you don't believe me, fill up a plastic cup sometime. Use a nail, and punch one hole in the cup, near the bottom. It'll spray really far. Punch five holes, each of those holes will spray, but to a much shorter distance. Punch twenty holes all around, and the water from each hole will come out just a dribble, even though a greater amount of water will be leaving the cup per unit of time than if you punched only one hole.

Try it. It's really true.

If you don't want to get soaked, drill more holes, the more the better, at the same level, all the way around. More holes all around won't spray remotely as far as a few on just one side, and you'll actually stay dry when you go to water your pot.

[LJA]

Once the roots grow down into the reservoir does that mandate promptly repotting into a larger container? I'm wondering what if the roots grow down into the reservoir in the center where you really can't see... Or is it no big deal...?

Maire, interesting question.

My experience tells me that orchid roots will grow into an environment where the orchid feels it will thrive best. For example, semi-terrestrial species will almost never put out aerial roots, even if the plants are completely overcrowded inside a pot. Similarly, roots growing into an environment that's not suitable will change their direction of growth to avoid that environment, and that includes an environment with way too much water.

If a root happens to grow into the reservoir of its own accord, it's because that's where it wanted to grow. No cause for alarm. A healthy orchid plant knows what it's doing. If, on the other hand, roots have completely filled up the container, looking like they're about to bust out, that's when it's time to repot.

All of this, of course, assumes that the plant is healthy, that the size and water retention of the medium is appropriate for the plant being cultivated, and that no roots were forced down into the reservoir during repotting. The media won't decompose, but healthy roots *will* fill up the pot. That's when you know it's time.

[dosal]

Actually, I did drill holes all around in the beginning. I ended up with a fountain. Now I drill or rather melt more holes in one side. You can also make more holes upward on the same side if you want more air ventilation.

[LJA]

dosal, have you found that the extra ventilation with more holes above the reservoir helps with this kind of growing? I would have thought that, as coarse as the media is, plenty of air would be reaching the roots as is.

[dosal]

I haven't put any holes above the initial drainage holes. I am simply repeating what I have heard could be done. It might help if you get rot in the roots. For instance I had a Phal that I repotted the other day and the roots were a stinking rotten mess below a certain point. I should add that I had quite a lot of moss growing on top of the LECA which would have cut off the air circulation. In this case extra holes would have been advantageous.

[LJA]

If that's the case, then there really *is* no way to tell when it's time to repot. Further, it seems then that this type of growing puts plants at a much greater risk of disaster.

So what's the advantage over traditional media and methods? Why all the hype?

[dosal]

Sorry I didn't get to this right away.
To me and to others the advantage in growing in LECA is that you can't overwater, repotting is a breeze as well. You re-use your old medium rather than getting new bark all the time. Many plants absolutely love the constant availability of fertilizer solution.
I know I am not going back to bark. I just have to be more attentive to keep moss from growing on the medium.
At present I am experimenting with Diatomite and so far my plants love this even more.

[LJA]

Sorry I didn't get to this right away.

LOL! No prob. (Though, had it been much longer, I would've started getting worried that I had run you off!!!)

So how *do* you tell when it's repotting time? With bark based, the medium gives me visual cues, but with something that doesn't decompose--especially if it's not potted in a translucent container--how do you decide?

Diatomite: I'm only familiar with that in powdered form. Are you sprinkling it in?

[dosal]

for Diatomite check out this link:http://diatomiteusa.com/shop.htm

When it comes to repotting in S/H I do when the roots outgrow the pot or when the plant grows over the rim. You can overpot without a problem. If you have a husky plant to start out with I would even recommend it. Don't forget the LECA can't decompose which is the main reason plants are being kept in tighter confines with bark.