Houseplant · Asparagaceae
Asparagus Fern
Asparagus aethiopicus
Soft, feathery, and almost impossible to kill as long as you don't drown it.
Bright indirect
Every 7–10 days
50–77°F · 10–25°C
USDA 9–11
Overview
The asparagus fern looks every bit the delicate fern, with soft, feathery sprays that arch and tumble over the side of a pot. It isn't a fern at all. It belongs to the asparagus family, and those feathery 'leaves' are actually flattened stems called cladodes doing the work of leaves.
As a houseplant it asks for very little. It grows fast, takes bright indirect light, and stores water in tuberous roots that let it ride out a missed watering far better than a true fern would. Give it a warm spot and a pot that drains, and it fills out into a lush green cloud.
The one catch is the berries. In summer it sets tiny white flowers that turn into bright red fruit, and those berries are the main reason to keep it away from pets and small children. The sap can also irritate skin, so it pays to wear gloves whenever you prune it back.
Care
The short version: bright indirect light, water once the top few centimeters dry out, feed monthly through spring and summer, and keep the berries away from pets and kids.
Light
Give it bright indirect light for the fullest, densest growth. It will get by in partial shade or a little direct sun, but too little light leaves it thin and stretched, while harsh midday sun scorches the fine foliage.
Water
Keep the soil lightly moist while it's growing, but let the top few centimeters dry out before you water again. The tuberous roots store water, so they rot in a pot that stays soggy. Ease off through the winter when growth slows.
Soil
Plant it in a well-draining, fertile potting mix rich in organic matter. A slightly acidic pH of 6.0 to 6.8 suits it, and good drainage is what keeps those tubers from sitting wet.
Temperature
It's happiest between 50°F and 77°F (10°C to 25°C). It has no tolerance for frost, so keep it indoors or move it inside well before the first cold nights.
Humidity
Average room humidity, around 40% to 60%, keeps it looking its best. In very dry air the tips can brown, so group it with other plants or set it near a tray of water if your home runs arid.
Feeding
Feed once a month from spring through summer with a balanced water-soluble fertilizer cut to half strength. Stop feeding in fall and winter while the plant is resting.
Pruning
Cut yellowed or dead stems off at the base to keep it tidy, and trim back leggy growth to push out denser, fresher fronds. Wear gloves, since the foliage and sap can irritate skin.
Repotting
Move it up a pot size every 1 to 2 years, ideally in spring. You'll know it's overdue when the tuberous roots shove up above the soil, push through the drainage holes, or start to crack the pot.
Size & spacing
Indoors it reaches about 12 to 24 inches (30 to 60 cm) tall and spreads 24 to 35 inches (60 to 90 cm) wide, so give it room to arch out without crowding its neighbors.
Troubleshooting
Almost every problem with this plant traces back to water or light. Brown and crispy usually means too dry, yellow and dropping usually means too wet, and pale and stretched means it wants more light. Match what you see below and the fix is rarely complicated.
Yellowing fronds that drop their needles
Most of the time this is root rot from soil that stays too wet, since the tuberous roots store their own water and resent a soggy pot. Too little light or the natural aging of old stems can do it too. Let the top few centimeters dry before you water again, move the plant into brighter indirect light, and cut any fully yellow stems off at the base.
Fix:
- Allow the top few centimeters of soil to dry before rewatering
- Improve drainage and ensure the pot has open holes
- Move to a brighter spot with bright indirect light
- Remove fully yellowed stems at the base
Brown, crispy fronds shedding their needles
This is drought stress, often after the tubers dry out completely, sometimes made worse by hot dry air or harsh midday sun. Lift the pot; if it feels feather-light and the soil is bone dry, that confirms it. Soak the pot from the bottom to rehydrate it, move it out of direct sun into bright indirect light, and trim the browned stems.
Fix:
- Rehydrate by deep watering or bottom-soaking the pot
- Move out of harsh direct sun into bright indirect light
- Raise ambient humidity to around 40-60 percent
- Trim off browned stems
Thin, stretched stems with washed-out color
Pale, leggy growth means the plant is reaching for light it isn't getting, and a missed feeding through the growing season makes it worse. Look at the brighter side of the plant: if those stems stretch toward the window, low light is the cause. Move it somewhere brighter, feed monthly with diluted balanced fertilizer in spring and summer, and prune the leggy stems to push out denser regrowth.
Fix:
- Relocate to brighter indirect light
- Feed monthly with diluted balanced fertilizer in spring and summer
- Prune leggy stems to stimulate bushier regrowth
Toxicity
This is a toxic plant, and the bright red berries are the real hazard. They hold steroidal compounds called sapogenins that cause vomiting and stomach upset if eaten, and the sap can leave skin red and itchy after repeated contact. Keep it up out of reach of pets and children, and clear away any fallen berries.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
The ASPCA flags this plant for cats. Eating the bright red berries brings on vomiting, belly pain, and diarrhea, and brushing against the foliage over and over can leave the skin red and irritated.
Dogs Moderate
Dogs react much the same way. A mouthful of berries leads to vomiting and a sore stomach, while repeated contact with the sap can flare up as an itchy rash.
Horses Caution
The same steroidal saponins that trouble cats and dogs would unsettle a horse, so keep grazing animals away from the berries and foliage even though horses rarely seek the plant out.
Rabbits Caution
Don't offer any part of this plant to a rabbit. The saponins in the berries and stems aren't safe for a small grazer, and there's nothing here worth the risk.
Livestock Caution
Cattle, goats, and sheep can pick up the same stomach upset from the saponin-laden berries and foliage. Fence it off from pasture where animals might browse it.
Birds Caution
Birds eat and spread the red berries in the wild, which is how this plant turns invasive, but the fruit can still irritate a pet bird's gut. Keep cage birds away from it to be safe.
People Caution
No part of this plant is meant to be eaten, and the berries can cause stomach pain and diarrhea if a child swallows them. The sap stings bare skin too, so wear gloves when you prune or repot.
Wear gloves when pruning or repotting, as the sap and foliage can trigger allergic dermatitis with repeated skin exposure.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
A few named forms turn up in garden centers, and they differ mostly in how the fronds are held. These are the ones worth knowing.
'Sprengeri'
This is the classic Sprenger's form most people grow indoors, with loose, arching, feathery stems that spill over the edge of a pot.
'Myersii' (foxtail fern)
The foxtail fern trades the arching sprays for dense, upright, plume-like fronds that really do look like a row of fox tails.
'Cwebe'
Its arching stems push out coppery-bronze new growth that settles down to green as it matures.
How to propagate
Making more asparagus ferns is easy, and the simplest route is to split a plant you already have when you repot it in spring.
DivisionEasy
Spring, ideally at repotting time · 2 to 4 weeks
Division is the easy way, and spring at repotting time is the moment to do it. Lift the whole plant, then cut or simply pull the tuberous clump into sections, each with its own roots and a few stems, and pot them up on their own. Each piece settles in and starts growing within 2 to 4 weeks.
SeedModerate
Spring · Several weeks to germinate, months to fill out
Growing from seed takes patience and is best started in spring. Clean the seed out of the ripe red berries with gloves on, since the fruit irritates skin, then sow it in a warm, moist mix. Expect several weeks to germinate and a good few months before the seedlings fill out, and the results come up slower and patchier than division.
Myths
Asparagus fern is a true fern that reproduces from spores.
The name and the feathery look fool people, but this is not a fern at all. It's a flowering plant in the family Asparagaceae that makes flowers, berries, and seeds, and those soft feathery 'leaves' are really flattened stems called cladodes.
Like a real fern, it wants constantly wet soil and deep shade.
Its tuberous roots store their own water, so the plant shrugs off a dry spell far better than a true fern would. It also wants bright indirect light, not deep shade, and soggy soil is the fastest way to rot it.