How to Identify a Houseplant You Inherited, Bought Unlabelled or Forgot

Somebody gave you a plant. Or you bought one labelled "green plant, 12cm". Or you inherited a houseful of them and nobody wrote anything down.

Knowing the species is not trivia. A calathea and a snake plant sitting on the same shelf want almost opposite treatment, and treating either like the other kills it within a couple of months. So it is worth ten minutes.

Start with growth habit, not leaf shape

Most people begin by comparing a leaf to photos, which is slow because thousands of houseplants have broadly similar leaves. Habit narrows things much faster.

• Trailing or climbing vine. Pothos, philodendron, hoya, string of hearts, tradescantia, ivy, syngonium.
• Upright single stem with large leaves. Monstera, rubber plant, fiddle leaf fig, dieffenbachia, dracaena.
• Rosette, leaves radiating from a central point at soil level. Bromeliad, echeveria, haworthia, African violet, bird's nest fern.
• Clump of upright blades from the soil. Snake plant, spider plant, aspidistra, chlorophytum, dracaena varieties.
• Fronds. Ferns and palms. Ferns unfurl from a coiled fiddlehead, palms do not.
• Thick fleshy leaves or stems. Succulents and cacti.

Then check three things on the plant

Leaf arrangement. Do leaves come off the stem in opposite pairs or alternate one at a time? Most houseplants alternate, so opposite arrangement is immediately informative.

Sap. Break a leaf stalk. Milky white sap points at the fig family or euphorbias. Clear sap is most other things. Wash your hands, since several of these irritate skin.

Stem texture. Woody, fleshy, or a soft green vine. Aerial roots along the stem point at climbing aroids like monstera and philodendron.

The six groups people confuse

1. Pothos vs heartleaf philodendron. Pothos leaves are thicker, slightly waxy, with an asymmetric base. Philodendron leaves are thinner, softer, more evenly heart shaped, and new growth emerges wrapped in a papery sheath called a cataphyll. Pothos has no cataphyll.Check for the sheath
2. Monstera deliciosa vs adansonii. Deliciosa is large with splits that reach the edge. Adansonii is smaller with holes that stay enclosed inside the leaf.Do the holes reach the edge?
3. Snake plant vs dracaena. Snake plant blades are thick, stiff and rise straight from soil level. Dracaena has a visible woody stem with softer leaves along it.Is there a stem?
4. ZZ plant vs philodendron. ZZ leaflets are thick, glossy and stiff, arranged along a wand-like stalk that arches from the soil. Nothing else in a normal collection looks quite like it.Feel the thickness
5. Calathea vs maranta vs stromanthe. All are prayer plants that fold up at night. Maranta leaves lie more horizontally with rounded ends, calathea stands more upright, stromanthe usually has pink or red undersides.Look underneath
6. Sago palm vs a real palm. Sago is a cycad, not a palm, with stiff sharp leaflets and a squat pineapple-like trunk. It is also seriously toxic to dogs, unlike true palms.Worth getting right

What to photograph if you are using an app

The single biggest factor in whether you get a correct identification is the photo, not the app.

1. One leaf, flat, against a plain background. A hand, a sheet of paper, a wall. Not against the rest of the plant.Contrast
2. The stem junction, so leaf arrangement and any sheath or aerial root is visible.The attachment
3. The whole plant in its pot, so growth habit is clear.Habit
4. The leaf underside, which is where colour, hairs and venation often differ between lookalikes.Underside
5. Flowers if there are any. Flower structure is the most reliable feature in botany and beats leaves every time.If flowering
6. Daylight, no flash. Flash blows out the surface texture the identification depends on.Light

Two things that will trip you up

Juvenile leaves. A young monstera has solid heart shaped leaves with none of the splits it is known for. Plenty of climbing aroids look nothing like their mature form for the first couple of years.

Cultivars. Variegated, dwarf and coloured varieties are bred to look different from the wild species. A Philodendron Birkin looks nothing like a wild philodendron, and a variegated monstera can confuse an identification that would be trivial on a plain green one.

Why it changes what you do

Once you have the name, everything else follows. Watering, light, whether it wants humidity, whether it is safe around a cat, whether it likes being pot bound. Those answers differ enormously between plants that sit next to each other in the same shop.

Take the two most common shelf neighbours as an example. A snake plant wants to dry out completely, tolerates a dark hallway and rots if you are attentive. A calathea wants consistently moist soil, filtered water and humidity, and browns off if you forget it once. Same shelf, same shop, opposite instructions.

Photograph a leaf with the stem visible and Identium will name it, tell you whether it is toxic to cats and dogs, and build a care schedule for that species rather than for houseplants in general.