OnMySill

Button Fern / New Zealand Button Fern

Pellaea rotundifolia

description

Button Fern is a compact fern with small round leaflets along dark wiry stems.

benefits

  • Low—light tolerant
  • Pet-friendly, non-toxic to animals
  • Suitable for containers

How to care for Button Fern

sunlight

In New Zealand, Button Fern grows in sheltered, filtered light rather than open sun. Give it a bright spot with softened light indoors.

Bright indirect light

Place near an east or north-facing window, or a few feet back from a brighter window. This supports compact, healthy fronds without overheating the foliage.

Medium indirect light

It tolerates a moderately lit room, but growth will be slower. Move it closer to the window if new fronds are sparse or stretched.

A sheer curtain is useful at sunny windows: it keeps the light bright while protecting the delicate leaflets.
Avoid hot, direct midday sun, which can scorch and crisp the fronds.

watering

Let the potting mix dry slightly between waterings. Button Fern is less thirsty than many ferns and is more likely to suffer from constantly wet soil than a short dry spell.

Spring to early autumn

Water thoroughly about every 7-10 days in bright, warm conditions, letting excess drain away. Check first: water when the top 1-2 inches of mix feel dry and the pot is noticeably lighter.

Winter and low light

Growth slows in cooler, dimmer months, so watering may be needed only every 2-3 weeks. Let more of the mix dry, but do not leave the root ball bone dry for long.

Use the pot weight as your guide: a light pot needs water, while a heavy pot still has moisture below the surface.

These timings are starting points. A small terracotta pot, warm room, or airy mix dries faster, while low light, a large pot, and dense soil keep moisture longer.

Never leave the pot standing in water, as soggy roots can quickly lead to rot.

humidity

Preferred humidity

40-60%

Native to New Zealand’s relatively dry, sheltered forest and rocky habitats, Button Fern is more forgiving of average home air than many ferns. It is usually comfortable at 35-60% humidity, but appreciates a little extra moisture when heating or air conditioning is running.

Crisp brown leaflet edges and curling fronds usually mean the air is too dry, especially if the compost is not dry.

How to increase humidity

  • Group it with other plants or use a small humidifier nearby.
  • Keep it away from radiators, heating vents, and strong air conditioning.
  • Use a pebble tray with water beneath the pot, keeping the pot above the waterline.

temperature

Preferred temperature

16-24°C (60-75°F)

Winter minimum

10°C (50°F)

Native to New Zealand, Button Fern prefers mild, steady indoor temperatures. Keep it away from hot radiators and air conditioning, which can dry and stress the fronds.

Place it in a room that stays above 10°C (50°F), especially near windows in winter.
Cold drafts and sudden temperature drops can cause fronds to brown or shed.

nutrition

March - August

Feed about once a month while new fronds are appearing, using a balanced liquid houseplant fertilizer diluted to half strength. Do not feed in autumn and winter unless the fern is still growing actively in warm, bright conditions, then feed no more than every 6-8 weeks.

Nitrogen

Nitrogen supports the Button Fern's fresh green fronds. A gentle, regular dose of balanced fertilizer is enough, as heavy feeding can scorch its fine roots.

Apply fertilizer to already moist soil, then occasionally flush the pot with water to prevent fertilizer salts from building up.

soil

Light, humus-rich, free-draining soil

Button Fern has fine roots that dislike sitting wet, but it also dries out faster than many ferns. Use a quality indoor potting mix loosened with perlite or pumice and a little fine bark, so it holds some moisture while excess water drains freely.

pH 6,0 - 7,0

This is slightly acidic to neutral. Most standard houseplant mixes are suitable. Avoid strongly acidic mixes made for acid-loving plants, and refresh compacted soil when repotting.

Choose a pot with drainage holes, and do not pack the mix down tightly around the roots.