Monitoring a Houseplant Shelf with a Phone

The setup

Four plants on a 2×2 KALLAX shelf: a Monstera deliciosa, a Pothos (Epipremnum aureum), a snake plant (Dracaena trifasciata), and a peace lily (Spathiphyllum wallisii). A mid-range Android phone (nothing special — a Redmi Note 11) in a simple wall-mounted clip, plugged in at all times.

One capture per plant every Sunday morning — four captures, takes about three minutes in total.

What it found

After six weeks, the chlorophyll index on the Pothos dropped steadily from 0.68 to 0.51. Without Sproutcast I probably would have noticed the yellowing in week four or five. The data showed it starting in week two.

The cause: the Pothos was behind the Monstera and was getting significantly less light than the other three plants. Moving it to the front of the shelf (and the Monstera to the side where it gets indirect sun) reversed the trend within three weeks.

The care log correlation

Once I noticed the drop in the app, I added a note in the care log — "Moved Pothos to front shelf, Feb 7". Looking at the metric chart now, you can see the exact inflection point. That kind of visible before/after is really satisfying.

What I don't bother measuring

The snake plant barely changes week-to-week — it is exactly as drought-tolerant as advertised. I dropped it to monthly captures and disabled the turgor alert (it goes below threshold whenever it is slightly dry, which is fine for this species). Sproutcast lets you configure alerts per-plant so the snake plant doesn't flood me with false positives.

Cost

Zero. The app is free. The phone was already mine. The KALLAX was already there.