Overwatering in Orchiata Bark?
 

Hi guys, I recently repotted some of my orchids in 100% Orchiata bark. However, I've found that the bark mix dries out pretty fast and unevenly due to the side holes. Roots on the sides of the pot will dry out super quickly, and I find myself flushing water through the pot twice a day.

I'm currently using the "Power" size, 3/8” to 1/2" bark. Will this constant watering rot the roots in the middle of the pot?

How big is the pot? If the pot is too large for the plant, you can still keep the middle too wet. Unless you live in the desert, in the summer, I doubt that you need to water that often. Depending on plant/pot size, every two days is probably sufficient, certainly once a day is plenty even in the hottest, driest weather. Water doesn't rot roots, lack of air rots roots. So stick your finger into the middle of the pot, and feel how wet it is or isn't.


Even if the bark at the outer edges feels dry, you still have humidity within the pot from that damper parts. And "humid air" rather than "sopping wet" is the goal.

The pot is about 5 inches in diameter.

The middle of the pot is definitely still wet when I water. Unlike moss, I thought that bark retains air pockets, so I wasn't sure if the roots in the middle would still rot or not.

I think reduce the watering frequency a bit. The bark does contain air pockets, so it is harder to overwater, but not impossible. Don't worry about some drying around edges - that's actually ideal. Every 2-3 days should be plenty of water for most genera.

Don’t forget the cell morphology.

If the roots that are staying wet grew in that environment, they should be fine. If they grew in drier root zone conditions, then you started watering that heavily, they may succumb.

I'm with Roberta. From what you describe, it seems like watering every other day should be sufficient. And you can perhaps cut that back over time as your plants adjust to the new medium. I think you have gone from sphagnum moss to Orchiata? So it's normal that you will now have to water more often. All of mine are in Orchiata, and I water anywhere from two to three times a week, depending on the plant and the humidity in the house.

I know what you mean when you say the roots next to the sides of the pot will look silver pretty quickly after watering. My pots have side holes, too. So I generally go by the weight of the pot to determine if it needs water. I don't use a scale, I just know from longtime experience when the pot is getting dry all the way through.

Also, many of my Phals have aerial roots and/or roots close to the top of the pot. If it's been more than a couple of days since I've watered, but the pot still feels like it's got moisture in the middle, I will simply mist all the external roots I can see. Plus, I mist them every time I water, anyway, since I like the aerial roots, and if I don't they will dry up quickly in my home.

Every bark product I've used is hydrophobic at first, with orchiata being no different. I don't add additional water during the initial period after potting so that the new roots are "incentivized" to search for water and extend. I don't know if this is actually what happens, but I haven't seen negative effects from my orchids sitting in drier than normal media for a few weeks.