Carnivorous Plants/Flooding CP and Oxygen
few days ago I asked you if I could flood my Sarracenia while on leave for 3 days. You told me that due to high temperatures (90 F°) and stagnant water, roots might not be oxygenated enough and rot/die.
1.) Now my questions is, how would it be if I flood the plant to 2/3 and leave the upper 1/3 of the soil out of water? Would it change something? Is oxygen to the roots only transported via water or also with normal outside air via the soil?
2.) On the other hand, I have several 35 cm pots as seen on attached pictures with water reservoir. If I top water, water flows out from downside, all fine. However if I water from tray, the water cannot be absorbed. I guess since the drainage whole + water reservoir are taking several inches in height, the soil won´t be able to absorb it... I filled the whole from bottom with long dried sphagnum in the hope that capillary effect will take place, but instead it just stuck the whole, so when I water from top it won´t drain out anymore and remain stagnant too... Should I replace the long sphagnum with normal soil? Would it be better for capillarity?
I hope my question is easy to understand, if not I will take some pictures tomorrow for better explanation.
Thanks and good job on the latest July video, your plants look great!
Having pots just sit 1/3 of the way in water so that the upper 2/3's are above the water line is fine. That's what we do in our pools. It varies on water depth from pool to pool, but we try never to be more than half-way up the pot. In summer when we transplant plants, you can take see when the soil is dropped out that the part of the soil that is in the water is lighter colored and foul smelling. The plants won't grow their roots into that layer.
I would just avoid the types of pots you're showing altogether. These are designed for regular plants that want the soil just damp. To work around the chambers you have to place the pots deeper in the water, and you don't always know when the soil is getting water, especially when levels start getting low.
Here's a whole different alternative to watering when you're away. Set up a drip watering system. If you have a good garden center nearby they should carry some type of this, and they are not that expensive to set up. Here an example of a brand I use carried here in the US: http://www.raindrip.com/
What you would do is put out a main line from a faucet, then connect the smaller lines to each pot. They make either drippers or small sprinkler heads that attach to the smaller lines. You then put an electronic water controller at the faucet to come on at set intervals. You could still leave the plants in shallow water trays to catch runoff, and provide extra insurance against drying out. This system is great even when you're home, it just isn't very aesthetic. I use this on our Darlingtonia and love it.
The water lines and drippers tend to be very inexpensive, but where you should spend some money is on the controller. We've found ones made by Orbit to be reliable. Avoid the controllers that Rain Drip makes if you have that brand in Germany. All the other Rain Drip parts are great, just not the water controllers.