Show HN: Xenolab – Rasp Pi monitor for my pet carnivourus plants

54 malux85 17 5/10/2025, 8:58:27 PM github.com ↗

Comments (17)

teruakohatu · 2h ago
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.
darreninthenet · 1h ago
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

dfc · 46m ago
Water butt (noun) - British: a large container for collecting or storing a liquid (such as rainwater)

This is so much better than "rain barrel".

teaearlgraycold · 46m ago
Depends on your tap water. Hetch Hetchy water has worked perfectly for me for years.
nwellinghoff · 2h ago
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.
barbazoo · 1h ago
If it’s the water, could it help to let it stand for a while? I do that to get rid of the chlorine.
lagniappe · 1h ago
Many American cities use chloramine, which requires something like Sodium thiosulfate, but then you're left with Ammonia, which may or may not be desired.
malux85 · 2h ago
I think it's something in our water, I have to give them purified water which I buy.
floam · 2h ago
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!

chneu · 1h ago
This setup would take like 10 minutes in Home Assistant.
asmodeuslucifer · 1h ago
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 · 2h ago
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 · 2h ago
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 · 1h ago
Great work! It would be interesting to have a side by side comparison with a plant grown without monitoring.
giuliomagnifico · 3h ago
Impressive work for monitoring some plants! I hope they don’t bite you :)
omneity · 1h ago
The “torque” of these plants is very low usually. You barely feel the pressure.

Source: My finger, unscathed after an encounter with a Dionaea.

cactusplant7374 · 2h ago
That’s really cool. Thanks for sharing.