Show HN: Xenolab – Rasp Pi monitor for my pet carnivourus plants
13 comments
·May 10, 2025teruakohatu
darreninthenet
Just to reiterate what's already been said - don't use tap water. We have a carnivorous plant expert/dealer local to us and he just collects and uses rainwater, as he says tap water will kill them.
Simple waterbutt attached to the drain pipe off the guttering and you get infinite free water for them
barbazoo
If it’s the water, could it help to let it stand for a while? I do that to get rid of the chlorine.
nwellinghoff
Its the water. I have a ro/DI system and use that water. All of the cool low nutrients species have been living for years no problem.
malux85
I think it's something in our water, I have to give them purified water which I buy.
floam
I bought a Venus fly trap about 10 years ago, and recall wanting to stick some RGB LEDs on an “Arduino or something” to get them to turn on and off in sync with the sun. I was hung up on the idea that this is in my windowsill, so the data on sunrise and sunset I could get from a photoresistor. It would also monitor moisture.
This is so cool!
asmodeuslucifer
I have some venus fly traps, they are suspended from the side a of a fish tank with the bottom of their container in the (presumably nutritious for them) fish water. Unrelated to blackrabbit17s setup, home assistant controls the lights and pumps.
aucisson_masque
I can appreciate the engineering but damn this look extreme.
My carnivorous plants are by the window and I water them once in a while, never had issue.
I thought about automating water supply but even me, a geek, realized it would be a waste of time.
anfractuosity
You might also be interested in this - https://docs.backyardbrains.com/retired/experiments/Plants_V... where they monitor the electrical spikes of the traps.
You can also apparently electrically trigger the closing of fly trap - https://www.tandfonline.com/doi/full/10.4161/psb.2.3.4217
omneity
Great work! It would be interesting to have a side by side comparison with a plant grown without monitoring.
giuliomagnifico
Impressive work for monitoring some plants! I hope they don’t bite you :)
omneity
The “torque” of these plants is very low usually. You barely feel the pressure.
Source: My finger, unscathed from a Dionaea encounter.
cactusplant7374
That’s really cool. Thanks for sharing.
I need this! I am struggling to grow carnivorous plants in New Zealand. I think I am giving them what they supposedly need but I just can’t win.