Swiss cheese vine

Swiss cheese vine: how do you recognise it?

Habit

Climbing or trailing plant with thin stems and aerial roots; stems up to 2–3 m indoors.

Leaves

Heart-shaped to oval, 10–25 cm, fresh green and thin, with a row of oval holes either side of the midrib.

Roots

Ordinary roots in the pot and aerial roots on the stem, which it uses to cling on.

Flowers

A typical arum flower with a spathe and spadix, but it rarely flowers indoors.

Sap

Contains calcium oxalate crystals, which irritate the mouth and throat if eaten.

Plants: March–May · Pruning: March–April

Why grow it?

• Striking leaves full of holes, even on young plants.
• Fast-growing, as a climber on a moss pole or as a trailing plant.
• Easy: tolerates a bright spot without fierce sun and the odd missed watering.
• Cuttings root readily in a glass of water.
• More compact than the big Swiss cheese plant, so it suits a smaller room too.

Swiss cheese vine: where does it grow best?

• Bright light to partial shade, out of fierce midday sun: a spot 1–2 m from an east- or west-facing window is ideal.
• Warm, ideally 18–25 °C and never below 12 °C; no draughts or cold window panes in winter.
• Open, airy houseplant compost mixed with bark or perlite, so water never sits around the roots.
• Higher humidity helps: it does well in a bathroom with daylight or grouped with other plants.

Light

Bright, out of direct sun

Potting soil

Multi-purpose compost or airy, humus-rich compost

Acidity

Acid or neutral

Watering

Moderately

Size

2 m tall, 0.5 m wide

Temperature

Minimum 12 °C

Goes well with

• Pothos: Another fast climber or trailer with the same care needs.
• Philodendron: Likes the same light and warmth; together they make a lush green corner.
• Boston fern: Fine, fresh fronds as a contrast, and together they raise the humidity.
• Calathea: Patterned leaves beside the holey foliage, for a spot out of direct sun.

Swiss cheese vine: when and how to plant it?

Plant in March–May.

1. Repot in spring, from March to May, every one or two years or when roots grow out of the pot.
2. Choose a pot one size larger, with a drainage hole.
3. Use an airy mix: houseplant compost with a third bark, coir or perlite.
4. Put a moss pole or climbing support in the pot before the plant, so you do not damage the roots.
5. Set the plant at the same depth as before, tie the stems loosely to the pole and push the aerial roots into the moss.
6. Water, let it drain well and keep it out of the sun for a week.

Care

Watering

Water when the top 2–3 cm of compost is dry; less in winter. Never leave water in the saucer.

Feeding

From April to September, half-strength houseplant feed every two to four weeks.

Humidity

Mist the leaves now and then or stand the pot on a tray of wet clay pebbles.

Support

Tie new stems to the moss pole and keep the moss damp so the aerial roots grow into it.

Leaves

Wipe the leaves with a damp cloth; clean leaves catch more light.

Tip: Give it a moss pole to climb: climbing stems produce bigger leaves with more holes than trailing ones.

Swiss cheese vine: when to prune it?

Pruning months: March–April.

When: Not needed, but in March–April you can shorten stems that are too long or bare.

How:

• Cut just above a node, where a leaf joins the stem; new growth starts there.
• Use the pieces you cut off as cuttings.
• Remove yellow and damaged leaves along the stem.
• Wear gloves: the sap can irritate the skin.

Caution: The sap irritates skin and eyes. Wash your hands after pruning and keep the trimmings out of reach of children and pets.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings in water

Cut a piece of stem with at least one node, ideally with an aerial root and a leaf. Stand it in a glass of water in good light; after 2–4 weeks it has roots and can be potted up.

Cuttings in compost or moss

Lay a cutting with a node in moist, airy cutting compost or sphagnum moss, under plastic and warm (20–25 °C).

Swiss cheese vine: how does it get through the winter?

• Houseplant: keep it warm in winter, ideally above 15 °C and never below 12 °C.
• Light levels drop: move it a little closer to the window, but not against a cold pane.
• Water less and do not feed from October to March.
• Do not stand it above a radiator: the hot, dry air causes brown leaf edges and red spider mite.

Diseases and pests

• Yellow leaves: Usually too much water or a pot that stays too wet, sometimes with root rot. Let the compost dry out more and repot into an airy mix if the roots are brown and soft.
• Brown leaf edges: Air too dry or too little water. Move it away from the heating and raise the humidity.
• Small leaves without holes: Too little light or no support to climb. Give it more light and a moss pole.
• Red spider mite and thrips: Fine speckling or silvery patches on the leaves, sometimes webbing. Rinse the plant in the shower and repeat after a week.

Through the year

• January: Little water, no feed. Away from the radiator.
• March: Prune and take cuttings. Repot if needed.
• April: Prune if still needed. Repot. Start feeding.
• May: Repot. Tie new stems to the moss pole.
• June: Growing. Feed and water when the surface is dry.
• July: Take cuttings. Wipe the leaves. Watch for red spider mite.
• August: Feed. Keep the humidity up.
• September: Last feed.
• October: Water less. Choose a brighter spot.
• December: Resting. Little water, no cold draughts.

Edible and useful

Not edible. All parts of these houseplants of the arum family are poisonous: the sap is full of needle-shaped crystals (calcium oxalate) which, when chewed, at once cause burning pain and swelling of the lips, mouth and throat, with drooling and sometimes vomiting. Most at risk are cats, which like to chew trailing stems and leaves, dogs, and young children playing on the floor. Hang climbers and trailing plants out of their reach, clear up cut stems and cuttings straight away, and do not put a glass of cuttings in water where a cat drinks from it. Wear gloves when pruning and repotting, do not rub your eyes, and wash your hands afterwards. If your cat or dog drools or its mouth swells, call your vet. If any is swallowed, call a poison centre (in Belgium 070 245 245) or your doctor at once.

Did you know?

• Nobody knows for certain why the leaves have holes. One explanation is that they let more light through to the leaves below.
• The species is named after Michel Adanson, an 18th-century French botanist.
• Young plants have different leaves from mature ones: the higher it climbs, the bigger and more perforated the leaves become.