Houseplant · Asparagaceae
Foxtail Fern
Asparagus densiflorus 'Myers'
Hand it bright indirect light and a pot that drains well, and the foxtail fern shoots up plumes that look like green bottle brushes.
Bright indirect
Every 7–10 days
50–77°F · 10–25°C
USDA 9–11
Overview
The foxtail fern catches nearly everyone out with that name. It has this soft, feathery look, yet it's not a fern in the slightest. It sits in the asparagus family, and rather than spreading by spores, it flowers, sets small red berries, and grows from seed. The 'Myers' form pushes up stiff, upright plumes that taper to a point, each one a chunky green bottle brush.
So what makes it such an easy houseplant? It comes down to the root. Tucked under the soil are fleshy tuberous roots that hold onto water, which means the plant takes a missed watering in stride far better than most. Give it bright indirect light, a pot that drains freely, and it asks for little else. Let it go and the clump fills out wide and lush, and that's exactly why it does so well in a hanging basket or up on a stand where the plumes can spill over the edge.
There are a couple of catches to know about, though. The whole plant is mildly toxic to cats and dogs, those bright berries most of all, and the sap can leave bare skin itchy. In frost-free spots it also slips out of gardens and naturalizes, so it's really one to keep potted and out of reach instead of turned loose in a warm-climate bed.
Care
The short version: bright indirect light, a pot that drains freely, and water only once the top few centimeters of soil have gone dry. Feed it monthly through spring and summer, keep it warm, and split it up whenever the tuberous roots start heaving it out of the pot.
Light
Set it in bright indirect light, the sort you get near a window that catches sun without the harsh midday glare hitting it. It handles partial sun and a touch of shade fine, but skimp on light and the plumes turn thin and pale while new growth crawls.
Water
Hold off watering until the top few centimeters of soil have dried, which usually works out to every 7 to 10 days. Those tuberous roots keep their own reserve, so a bit of drying between drinks actually suits it, whereas soil that stays wet rots the roots. Back off through winter as growth winds down.
Soil
Pot it up in a well-draining loamy potting mix that lets water pass through instead of pooling. Aim for a pH between 6.0 and 7.0, right around neutral, and it'll be content. Good drainage counts for more than anything here, because waterlogged roots are the quickest way to kill it.
Temperature
Regular room warmth of 50°F to 77°F (10°C to 25°C) is right where it likes to be. It can't take frost, so in winter keep it well back from cold windowsills and any chilly drafts.
Humidity
It's happiest with moderate humidity, somewhere around 40% to 60%, though it's not picky and gets on fine in average indoor air. Notice the plume tips browning in a dry, heated room? Just raise the humidity nearby.
Feeding
Feed it monthly from spring through summer using a balanced water-soluble fertilizer while it's actively growing. Ease off through the cold months when growth stalls, and rinse the pot out every so often so feeding salts don't collect.
Pruning
Snip spent or yellowed plumes off right at the base to keep the clump tidy and coax out fresh upright growth. Worn or damaged stems can be cut back hard in spring to give the plant a reset. Wear gloves while you're at it, since the sap can irritate skin.
Repotting
Repot it every 2 to 3 years, or earlier once those swollen tuberous roots start pushing the plant up and out of its pot. Roots circling the container and water racing straight through without soaking in are two more giveaways. Spring's the moment for it, and it often pairs up with dividing the clump.
Size & spacing
Indoors it climbs to 24 to 35 inches (60 to 90 cm) tall and spreads even wider, 3 to 4 feet (90 to 120 cm) across. Leave the clump plenty of room so the plumes can arch out freely, which is just why it works so well on a stand or in a hanging basket.
Troubleshooting
A foxtail fern lets you know something's off through its plumes well before the rest of it struggles. Yellowing, dropping, and brown tips each call for a different fix. Find the one that matches what you're seeing below and sort it before it spreads.
Plumes going yellow all over
Nine times out of ten, overwatering is what's behind this. Wet soil wears on those tuberous roots until the plumes lose their color, though a spot that's too dim or a plant that's short on food can look the same. Wait until the top few centimeters of soil have dried before your next watering, shift it somewhere brighter, and pick the monthly feeding back up once things are growing again.
Fix:
- Allow the top few centimeters of soil to dry before watering
- Move to a brighter spot with bright indirect light
- Resume monthly feeding during the growing season
Little needle leaves dropping everywhere
When a foxtail fern dries out too far, it drops its fine cladodes to save itself, and a quick move or a cold draft can set off the same shedding. So give it a good drink and get into a regular watering habit. Keep it clear of drafts and heat vents, park it in bright indirect light, and the mess tapers off.
Fix:
- Water thoroughly and maintain a consistent moisture cycle
- Keep the plant away from cold drafts and heat sources
- Provide steady bright indirect light
Crispy brown ends on the plumes
Usually it's dry air doing this, but soil that runs bone dry or a stash of leftover fertilizer salts can burn the tips just as easily. Bump up the humidity around it and hold the soil evenly moist while it's putting on growth. And now and then, run plain water through the pot to rinse away the salts that pile up from feeding.
Fix:
- Raise humidity around the plant
- Keep soil evenly moist during active growth
- Flush the soil periodically to leach excess salts
Toxicity
This really isn't a plant for growing where pets can reach it. The sap and those showy red berries are the problem, and the ASPCA has it under Asparagus Fern as toxic to cats and dogs. The same sapogenins are why you'll want to keep it from horses, rabbits, and grazing stock too. People aren't meant to eat any of it either, the berries are mildly poisonous, and the sap can bring up a rash, so glove up whenever you prune.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
The ASPCA flags the sapogenins here as toxic to cats. If yours snacks on the red berries, expect vomiting, an upset belly, and runny stools, and repeated rubbing against the foliage can leave the skin red and sore.
Dogs Moderate
It goes for dogs just like it does for cats. Berries that get chewed bring vomiting, diarrhea, and abdominal pain, and brushing up against the cut stems over and over can set off an itchy dermatitis.
Horses Caution
Nobody's logged a horse-specific case, but the same sapogenins that turn pet stomachs make this one worth keeping horses clear of. Don't give one the chance to graze the foliage or nose up the fallen berries.
Rabbits Caution
Count it out for rabbits too. Those berries and the sapogenin-loaded tissue can upset the gut, so park the pot and any dropped fruit somewhere they simply can't get to.
Livestock Caution
Goats, sheep, and cattle run into the very same toxin if they reach the foliage or the ripe red berries. Fence it off, or set it where the animals have no way to browse it.
Birds Caution
Out in the wild, birds eat the berries and scatter the seeds no worse for it, which is exactly how the plant gets loose, but you don't want a nosy pet bird picking at the fruit. Play it safe and keep it away from cage birds.
People Caution
None of this plant is for eating, and the red berries are mildly poisonous going down, so keep kids away from them. Handling the stems and sap without gloves can leave a rash, so slip some on before you prune or repot.
Wear gloves when pruning or repotting, as repeated skin contact with the sap can cause allergic dermatitis.
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
Two forms of Asparagus densiflorus show up going by the asparagus fern name, and honestly they couldn't grow more differently. Once you know which you've got, you'll know whether it stands tall or trails down.
Asparagus densiflorus 'Myers'
Here's the real foxtail, sending up dense, upright plumes that narrow to a tip and look for all the world like a bottle brush.
Asparagus densiflorus 'Sprengeri'
This is your run-of-the-mill asparagus fern, tumbling out in loose, arching, trailing stems rather than the stiff upright plumes you get on 'Myers'.
How to propagate
There are two ways to end up with more foxtail ferns: the fast one is splitting an existing clump, and the slow one is sowing the seed from its berries.
DivisionEasy
Spring or early summer at repotting · 4 to 8 weeks
Want the simple route to more plants? Division is it, and it lines up perfectly with a spring or early summer repot. Slide the plant out of its pot, then cut the fat tuberous clump into pieces, checking that each one takes some stems and some roots along with it. Pot those pieces separately and they'll get comfortable over the next 4 to 8 weeks.
SeedModerate
Spring · Several weeks to germinate, months to reach size
Seed is the patient person's method. Come spring, glove up and work the seed out of the ripe red berries, since the fruit can bother your skin, then tuck it into a warm, moist mix. Germination tends to drag on for several weeks and come up in fits and starts, and it's months more before those seedlings amount to much.
Myths
The foxtail fern is a true fern.
The name throws people off. It isn't a fern at all, it's part of the asparagus family, Asparagaceae. True ferns get around by spores, while this one flowers, sets red berries, and comes up from seed.
Because it's a fern, it must be safe around pets.
It's not a fern, and it's not safe either. The ASPCA has it under Asparagus Fern as toxic to cats and dogs, with the berries upsetting stomachs and the sap raising an itchy rash. So keep it well clear of anything that likes a chew.