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by db1 1721 days ago
I agree that watering only when the soil is completely dry is best. It's really hard to tell when that is with large plants thou. I have a massive monstera and a mid sized ficus. I can't pick these up to check their weight. Why are there no smart plant meters? Something I push into the soil and sends me a notification when the soil has completely dried out?

I've used those analog two prong moisture meters, but I'm looking for something that can just sit in the pot permanently..

6 comments

Moisture meters aside, I use plants as an example of the “expert problem”. Experts give advice that seems helpful, but only if you have intuition already.

“Completely dry” (or “plant is not hefty”) is not helpful to a beginner. There is basically a continuum of dryness, and with large plants, there’s a gradient as well (as you mention).

Paraphrased conversation I have had: “How much should I water this plant?” “Some, but not too much”

See also: cooking

>See also: cooking

Ah yes, the classic "bake 20-22 minutes, or until done."

It's like a conditional with "|| true"!

Just put a cable hanging from the leaf over a open circuit. when the leaf hangs the cable will descend and the circuit is closed. With a buzzer and a battery is all what you need.
Until you get the intuition of the soil, I would look at the plant itself. A plant drying out or in need of a good watering should show visible signs. I would google "thirsty <species>" to look for images of what a thirsty plant looks like of your species. In Monstera, google says a thirsty plant is one that is droopy and has yellow/"dry" spots on leaves that aren't near the bottom (ie. aren't being discarded as normal growth).
A convenient prong you can push into the soil is your finger - if it comes out with soil particles stuck to it, the plant doesn't need watering.
I do that quite a bit, but I have pots which are 12 inches deep. I want to know when the bottom has dried out.
There are, like the Xiaomi Mi Flora sensor (I think) or something like April Brother soil moisture sensor.

I have given up on those though because they're to expensive to put in every pot, and if they're not in every pot then I might as well manually check all the pots.

the two prong ones are resistive, and the exposed metal does indeed corrode quite quickly when in use.

there's also a single-prong capacitive type, only very marginally more expensive, with all metal parts covered in plastic film, which can sit in the soil indefinitely.