The moisture meter chart

Your meter says 40%. Which of your plants actually needs water?

Drag the needle to whatever your own meter reads, tell it what the pot is filled with, and every plant in our dataset sorts into thirsty, fine, or too wet. Works off whatever your meter prints — percent, a 1–10 probe, a 1–4 dial or a 1–3 chart. Every number free.

Plant Tender plant-tender.com/moisture-meter-chart

0100

Your meter reads 40%

Tell us the mix and the pot and every number below shifts to match — a cheap probe reads differently in chunky bark than in dense soil.

Water these 3

below the number they want

Leave these alone 34

inside their healthy band

Too wet for these 7

wetter than they tolerate

These are conductivity probes, not moisture sensors: fertiliser salt reads as wet, air pockets read as dry, and two meters in one pot disagree. Treat every number here as a band, and trust the direction it moves over a week more than any single reading.

Every species in our dataset, on every meter scale in circulation — and what the mix does to the number. Nothing here is gated.
what the meter we recommend prints …in chunky mix …in dense soil, shallow pot 1–10 probe 1–4 dial 1–3 chart At your reading
African VioletStreptocarpus ionanthus 35–65% 25–55% 45–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
AlocasiaAlocasia amazonica 40–68% 30–58% 50–78% 4–7 2–3Moist to Wet 2–3Moist to Wet In the healthy band
AloeAloe vera 10–35% 0–25% 20–45% 1–4 1–2Dry to Moist 1–2Dry to Moist Wetter than ideal
AnthuriumAnthurium andraeanum 38–68% 28–58% 48–78% 4–7 2–3Moist to Wet 2–3Moist to Wet In the healthy band
Areca PalmDypsis lutescens 38–68% 28–58% 48–78% 4–7 2–3Moist to Wet 2–3Moist to Wet In the healthy band
Arrowhead PlantSyngonium podophyllum 32–62% 22–52% 42–72% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Baby Rubber PlantPeperomia obtusifolia 20–50% 10–40% 30–60% 2–5 1–3Dry to Wet 1–2Dry to Moist In the healthy band
Bird of ParadiseStrelitzia nicolai 35–65% 25–55% 45–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
Boston FernNephrolepis exaltata 45–75% 35–65% 55–85% 5–8 2–4Moist to Soaked 2–3Moist to Wet Thirsty
BromeliadGuzmania lingulata 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
CalatheaGoeppertia orbifolia 42–70% 32–60% 52–80% 4–7 2–3Moist to Wet 2–3Moist to Wet Thirsty
Cast Iron PlantAspidistra elatior 22–55% 12–45% 32–65% 2–6 1–3Dry to Wet 1–2Dry to Moist In the healthy band
Chinese EvergreenAglaonema commutatum 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Chinese Money PlantPilea peperomioides 28–58% 18–48% 38–68% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Christmas CactusSchlumbergera truncata 25–55% 15–45% 35–65% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Corn PlantDracaena fragrans 25–55% 15–45% 35–65% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
CrotonCodiaeum variegatum 38–65% 28–55% 48–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
Dragon TreeDracaena marginata 22–50% 12–40% 32–60% 2–5 1–3Dry to Wet 1–2Dry to Moist In the healthy band
Dumb CaneDieffenbachia seguine 35–65% 25–55% 45–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
EcheveriaEcheveria elegans 8–30% 0–20% 18–40% 1–3 1–2Dry to Moist 1Dry Wetter than ideal
English IvyHedera helix 32–62% 22–52% 42–72% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Fiddle Leaf FigFicus lyrata 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Heartleaf PhilodendronPhilodendron hederaceum 28–58% 18–48% 38–68% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
HoyaHoya carnosa 20–50% 10–40% 30–60% 2–5 1–3Dry to Wet 1–2Dry to Moist In the healthy band
Inch PlantTradescantia zebrina 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Jade PlantCrassula ovata 10–35% 0–25% 20–45% 1–4 1–2Dry to Moist 1–2Dry to Moist Wetter than ideal
KalanchoeKalanchoe blossfeldiana 12–38% 2–28% 22–48% 1–4 1–2Dry to Moist 1–2Dry to Moist Wetter than ideal
Maidenhair FernAdiantum raddianum 50–80% 40–70% 60–90% 5–8 3–4Wet to Soaked 2–3Moist to Wet Thirsty
MonsteraMonstera deliciosa 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Moth OrchidPhalaenopsis amabilis 20–50% 10–40% 30–60% 2–5 1–3Dry to Wet 1–2Dry to Moist In the healthy band
Norfolk Island PineAraucaria heterophylla 35–65% 25–55% 45–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
Parlor PalmChamaedorea elegans 35–65% 25–55% 45–75% 4–7 2–3Moist to Wet 2Moist In the healthy band
Peace LilySpathiphyllum wallisii 40–70% 30–60% 50–80% 4–7 2–3Moist to Wet 2–3Moist to Wet In the healthy band
Ponytail PalmBeaucarnea recurvata 10–35% 0–25% 20–45% 1–4 1–2Dry to Moist 1–2Dry to Moist Wetter than ideal
PothosEpipremnum aureum 25–55% 15–45% 35–65% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Prayer PlantMaranta leuconeura 40–70% 30–60% 50–80% 4–7 2–3Moist to Wet 2–3Moist to Wet In the healthy band
Rubber PlantFicus elastica 28–58% 18–48% 38–68% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Snake PlantDracaena trifasciata 12–40% 2–30% 22–50% 1–4 1–2Dry to Moist 1–2Dry to Moist In the healthy band
Spider PlantChlorophytum comosum 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
String of PearlsCurio rowleyanus 8–30% 0–20% 18–40% 1–3 1–2Dry to Moist 1Dry Wetter than ideal
Umbrella PlantSchefflera arboricola 28–58% 18–48% 38–68% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Weeping FigFicus benjamina 30–60% 20–50% 40–70% 3–6 2–3Moist to Wet 1–2Dry to Moist In the healthy band
Zebra HaworthiaHaworthiopsis attenuata 8–30% 0–20% 18–40% 1–3 1–2Dry to Moist 1Dry Wetter than ideal
ZZ PlantZamioculcas zamiifolia 12–40% 2–30% 22–50% 1–4 1–2Dry to Moist 1–2Dry to Moist In the healthy band

Why this is a dial and not a table

Because the question people actually have is not "what should a monstera read". It is "my meter reads 40%, in chunky aroid mix, in a ten-inch pot, four days after I watered it — do I water it again?" That question has four variables, and the honest answer changes when any of them changes.

Every moisture chart on the internet answers the first question. It is the easier one, and it is the one that is nearly useless standing over a pot with a probe in your hand. So this page answers the second one, and the price of that is that you have to move something.

The meter scales, and why nobody prints all of them

There is no standard. The digital four-in-one we recommend prints a percentage — the display reads MOIST 48%, with the % sign on it, alongside a soil temperature and a light reading in lux. That is the scale this page leads with, and it is the scale our dataset is defined on.

Other meters do not agree. Plenty of probes print a bare 1–10 sweep with no units at all. The Luster Leaf-style analog dial prints a needle across four labelled zones — dry, moist, wet, soaked. The one competing chart in this niche uses 1–3. If you are holding one of those, the number on your meter and the number in most charts are not the same kind of thing.

None of them are calibrated to anything, ours included. They are galvanic probes: two dissimilar metals, a current between them, and an arbitrary scale silk-screened on the housing — a percent sign is a unit, not a calibration. So the table above prints every band on all four scales, which is the only way to make one number usable to someone holding a different meter — and it is the reason to treat any conversion as a band rather than an equals sign.

What your soil does to the number

This is the part every other chart omits, and it is larger than the difference between many species.

The counterintuitive one is that the height of the saturated zone is set by the soil's particle size, not by the pot's dimensions — which is why the same mix at the same probe depth reads high in a short pot and low in a tall one. Pick your mix and depth in the dial above and every number on the page shifts accordingly.

Fertilizer and tap-water mineral buildup also read as "wet" — if a pot never reads low, suspect salts before you suspect the plant.

How to take a reading that is worth comparing

Roughly two-thirds of the way down the pot, midway between the stem and the rim, angled slightly away from the centre. Push it in slowly — a probe that hits a root reads the root. Read it after about a minute, not instantly. Then take the next reading in the same spot, at the same depth, with the same meter, or the two numbers are not comparable to each other and none of this applies.

Wipe the probe dry afterwards. These things corrode, and a corroded probe reads low and then stops reading at all. That is not a defect; it is how a galvanic cell works.

Common questions

What should a moisture meter read for houseplants?

There is no single right number, which is why this page is a dial rather than a figure. Most foliage houseplants want water somewhere between 20% and 40%, but a snake plant wants to get down near 10% before you touch it and a fern is unhappy below 40% — a threefold difference between two plants on the same shelf. Set the dial above to your own reading, on whichever scale your own meter prints, and the whole dataset sorts itself around it.

My meter reads 1–10 and this chart says percent. How do I convert?

Pick your scale in the dial and every number on the page switches. Percent is the scale this page leads with because it is what the digital four-in-one we recommend actually prints — a percentage with a % sign next to it — and it is the scale our own dataset is defined on. But plenty of probes print something else, so every band here is also given on the 1–10 probe, 1–4 dial and 1–3 chart — including the analog dial's DRY/MOIST/WET zones. Do treat the conversion as a band rather than a point equivalence: these are conductivity probes with arbitrary printed scales, and no two manufacturers calibrate the same.

Why does the same plant need a different reading in different soil?

Because the meter is not measuring water. It is measuring how easily a current crosses between two dissimilar metals, and how easily that happens depends on what is touching the probe. In a chunky bark or aroid mix the probe is bridging air pockets as often as soil, so it reads about ten points low. In dense potting soil in a shallow pot the probe tip sits inside the permanently saturated zone at the bottom, so it reads about ten points high. Same plant, same true moisture, different number — which is why the mix and pot selectors move every value on this page.

Why does my moisture meter always read wet?

Fertilizer and tap-water mineral buildup also read as "wet" — if a pot never reads low, suspect salts before you suspect the plant. A pot that never drops below the middle of the scale is usually telling you about mineral buildup or about drainage, not about water. Flush the pot thoroughly, wait a week, and watch whether the number moves at all — a reading that will not fall is a different problem from a reading that falls slowly.

Is a cheap moisture meter accurate enough to trust?

Not in absolute terms, and spending more does not fix it — these are all unpowered galvanic probes, and two of them in the same pot routinely disagree by ten points or more. What a cheap probe is genuinely good at is relative measurement: the same meter, in the same spot, in the same pot, read over several weeks, tracks that pot drying out reliably. That is why this page ends where it does — one reading cannot be trusted, and how fast the pot dries out can.

Do I have to give you an email address to get the chart?

No. Every number is on this page, in the table, free, uncounted and unwalled. Copy it, screenshot it, print it, repost it. The one thing we do ask an address for is the printable one-page version — a sheet laid out to be taped inside a cupboard door — and that is a format, not data: there is not a single figure on it that is not already above. The competing chart in this niche gates the numbers themselves. We are not going to.

One reading can't be trusted. How fast the pot dries out can.

Everything above is one argument. A single number off a cheap conductivity probe is not a measurement — it is a data point with a large error bar, and the size of that error bar depends on your mix, your pot, your fertiliser habits and how old the probe is. This page exists to make that error bar visible rather than to pretend it away.

What survives all of it is the direction of travel. The same meter, the same spot, the same pot, read over a few weeks, tells you how fast this specific plant in this specific room actually dries — and that is the thing that answers "do I water it", which no chart on any website can do for you.

Scan it instead of squinting at it

Plant Tender reads your meter from a photo, remembers what each pot read last time, and turns the readings into how fast each pot actually dries out — then tells you water or leave-it-be, plant by plant. Free for your first 3 plants, and it works with the meter you already own.

Try it free Don't know the plant? Scan it

Every number here comes from Plant Tender's per-species dataset (version 3), which is version-controlled and changes through a reviewed commit rather than an edit nobody sees — internal:plant-tender-team (published horticultural consensus; soil temperatures re-baselined to root zone at v3; founder-reviewed, not horticulturist-verified). It is the same data the app itself uses to judge a reading, which is deliberate: a chart that disagrees with the product it advertises is worth nothing.