Old World Climbing Fern (Small-leaf Climbing Fern) care

Light

Bright but filtered. Old World Climbing Fern burns within days in unfiltered south-facing summer sun, and stops growing within months in deep shade. Thrives in bright, filtered light and can tolerate partial sun. In its native and invasive range it grows in full sun to partial shade. Indoors, a south- or west-facing conservatory is ideal. If you only have a south window, set the plant back 1.5 m or hang a sheer curtain — both knock the intensity down into the right range.

Watering

Watering old world climbing fern: when the top 2-3 cm of soil is dry, roughly every 5-7 days. The number that matters isn't the day of the week — it's how dry the top 2-3 cm of the pot feels. A finger in the soil tells you more than a watering app. After every watering, tip the saucer. Requires reliably moist conditions but tolerates brief dry spells better than many ferns. Water thoroughly and allow excess to drain. Consistent moisture promotes vigorous growth.

Soil and pot

Old World Climbing Fern grows best in fertile, moist, free-draining mix. A general-purpose potting mix enriched with leaf mould or composted bark works well. Slightly acidic to neutral pH (5.5–7.0) is suitable. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Old World Climbing Fern sits happiest at around 50-75% humidity and 18-30°C (64-86°F). Tolerates moderate household humidity better than most climbing ferns. Higher humidity promotes lusher growth. Mist occasionally in dry indoor conditions. If you keep the room above 18 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed old world climbing fern sparingly. Apply a balanced liquid fertiliser at half strength every 2-4 weeks during the growing season. This is a fast-growing species that benefits from regular feeding in containers. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on old world climbing fern in the Growli community. Each is annotated with the most common cause so you know where to start.

• Invasive escape risk — This species is a serious invasive pest in Florida and other warm, humid climates. Only grow in closed, controlled environments outside its native range.
• Rampant growth — Can quickly overwhelm a support structure. Prune back regularly to keep the plant to a manageable size.
• Spider mites — Prone in hot, dry conditions. Maintain humidity and treat with neem oil or insecticidal soap at first sight.
• Root-bound stress — Container plants become root-bound quickly. Repot every 1-2 years into a larger container with fresh mix.

Companion plants

Old World Climbing Fern pairs well with Heliconia, Strelitzia, Philodendron, and Plumeria. These are species with similar light and water needs, so you can group them in the same room or on the same shelf and water as a batch.

Propagation

Propagate from spores on moist sterile substrate at 22–26°C; spores are produced abundantly. Rhizome division also works well in spring. Note: do not spread spores or divisions in Florida or warm humid outdoor environments. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Old World Climbing Fern is pet-safe. Lygodium microphyllum is not listed by the ASPCA as toxic to dogs or cats. Like most true ferns, it is regarded as non-toxic; no harmful compounds specific to this species have been identified. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Old World Climbing Fern deep-dive guides

Every aspect of old world climbing fern care, each with its own calibrated guide:

• Common old world climbing fern problems & fixes
• Old World Climbing Fern watering schedule
• Old World Climbing Fern light requirements
• Best soil mix for old world climbing fern
• Old World Climbing Fern fertilizing guide
• When to repot old world climbing fern
• How to propagate old world climbing fern
• How to prune old world climbing fern
• What's eating my old world climbing fern?
• Old World Climbing Fern growth rate & size
• Old World Climbing Fern cold hardiness
• Old World Climbing Fern temperature & humidity
• Is old world climbing fern toxic to cats & dogs?
• Is old world climbing fern toxic to cats?
• Is old world climbing fern toxic to dogs?

Featured in these plant shortlists

Old World Climbing Fern qualifies for 10 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best pet-safe houseplants — Houseplants the ASPCA lists as non-toxic to cats and dogs — every one verified against the ASPCA toxic and non-toxic plant list.
• Best plants for a north-facing window — Houseplants for a north-facing window: bright, even, indirect light and no scorching direct sun. Each pick verified against its documented light needs.
• Best trailing & climbing houseplants — Vining and trailing houseplants for shelves, hanging pots, and moss poles — selected by growth habit.
• Best humidity-loving houseplants — Houseplants that thrive in a bathroom, kitchen, or by a humidifier — selected by documented humidity preference.
• Best pet-safe trailing & hanging plants — Trailing and climbing plants the ASPCA lists as non-toxic to cats and dogs — safe for shelves and hanging pots in a pet home.
• Best pet-safe plants for bright light — Non-toxic to cats and dogs and happy in a bright, sunny spot — safe plants for your best-lit windowsill.
• Best pet-safe large indoor plants — Big, floor-standing houseplants the ASPCA lists as non-toxic to cats and dogs — a statement plant that is safe around pets.
• Best fast-growing houseplants — Houseplants documented as fast or vigorous growers — quick to fill a pot, cover a pole or trail down a shelf.
• Best cat-safe plants — Houseplants the ASPCA lists as non-toxic to cats (and dogs) — safe greenery for a home with a curious cat.
• Best dog-safe plants — Houseplants the ASPCA lists as non-toxic to dogs (and cats) — safe greenery for a home with a curious dog.
• Browse all 30 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Old World Climbing Fern is also commonly called Small-leaf Climbing Fern or Climbing Fern.

• Antigonon leptopus care — light, water and common problems
• Dypsis Madagascariensis care — light, water and common problems
• Ravenea Glauca care — light, water and common problems
• All 11687 plant care guides in the Growli library