A Masterful Guide to the Asparagus Fern (Asparagus setaceus)
Welcome to the wonderful world of Asparagus.
No, not that Asparagus, you silly goose - I’m talking about the Asparagus setaceus – commonly known as the Asparagus Fern.
This beautiful tropical plant is one of my all-time terrarium favourites. I love its luscious, long, and looming fern-like fronds, and I positively relish how simple it is to care for.
Now, before I get carried away – let’s break down what we’ll cover in this guide.
I will be detailing an explosively comprehensive look into the family of Asparagus – covering everything from its geography and history to its basic and advanced care requirements.
I will also share my expert tips and tricks for getting the most out of Asparagus setaceus and its cousin, Asparagus plumosus, in your tropical closed terrariums.
AND, I will answer all of your most commonly asked questions, including common troubleshooting tips.
So, shall we all take a breath…and…begin!
Quick Guide
- Understanding Asparagus setaceus
- Characteristics and growth patterns of the Asparagus fern
- Why is the Asparagus fern such a great houseplant?
- How to Care for the Asparagus fern
- Advanced Care for the Asparagus Fern
- Is the Asparagus fern safe for pets?
- Terrariums and Asparagus Ferns
- Why you should use Asparagus ferns in your terrariums.
- Plants to pair with Asparagus spp.
- How to Use an Asparagus Fern in Your Terrarium
- More on the Asparagus Fern
1 | Understanding Asparagus setaceus
1.1 | Characteristics and growth patterns of the Asparagus fern
Swinging into the spotlight, not from the canopy but from the lush underbrush of Southern Africa, is our feathery friend: Asparagus setaceus.
This plant brings a dramatic flair to any setting it graces.
Known to the layman as the Asparagus Fern, this is not a true fern; this plant is a master of disguise – for its ferny fronds, in fact, belong to the lily family, who knew?!
- setaceus thrives as a climber in its native habitat, using its long, twining stems to reach the sun through the dense undergrowth.
In your home, it assumes a more domesticated persona, often draped elegantly in hanging baskets or cascading gracefully from a mantle with a myriad of fine, needle-like leaves.
Break down:
The plant's soft leaves, which resemble the delicate structure of ferns, are actually modified stems called cladodes.
These cladodes cluster along the creeping stems, creating a thick, lush, visually striking and inviting appearance.
Thanks to its vigorous climbing habit, Asparagus setaceus can reach lengths of several meters in the wild.
When kept in check within the confines of your home or a terrarium, it behaves more like a contained waterfall of green, adding height and texture to your indoor jungle.
In this terrarium I use Asparagus fern to compliment the verticality of my design
I’ll go a little further and explain just how brilliant this fern is as an addition to your home or workspace.
1.2 | Why is the Asparagus fern such a great houseplant?
Most of my friends and family are at least familiar with the Asparagus fern.
It has steadily grown in popularity – making it a certifiable staple in the houseplant community.
The fine leaves of the Asparagus fern
This should come as no surprise as it is a stunning plant that is relatively simple to look after (with the right care instructions, wink wink).
Here are some of the reasons I enjoy keeping the Asparagus fern as a houseplant:
- Visual Drama: The Asparagus fern, with its soft, billowy fronds, adds a unique natural flair to any room, bringing a piece of the jungle into any urban jungle. The looming fronds of this plant cast a complex multitude of shadows which enhance the depth and texture of a living space (or terrarium!).
- Air Quality: The Asparagus fern is a natural green guardian in the home, as it subtly removes common toxins like formaldehyde with its air-purifying fronds.
- Humidity Boosting: If you’re battling dry air, especially during those nippy winter months, this fern could be your trusty sidekick. It naturally bolsters ambient humidity levels.
- Stress Busting: Admittedly, all houseplants have well-documented mental health benefits. But on a personal level, I find there to be something so uniquely beautiful and endlessly tranquil about the Asparagus fern.
- Consistent Growth: This may not be a plus for some, but I love the potential for strong growth this plant offers. If maintained properly, you can achieve canopy-esque coverage in no time (how? We’ll explain later!)
- Aesthetic versatility: Its texture and form are a decorator's dream, blending well with both modern and traditional decor to enliven any space. Simply put, it’s classy as hell.
But let’s be honest, you already know how great this plant is. It’s not like you’re here to hate-read. Or maybe you are. Weirdo.
More importantly, let’s unveil how best to care for the Asparagus fern.
1.3 | How to Care for the Asparagus fern
Despite the aforementioned popularity, I often hear tell of difficulties encountered when caring for the Asparagus fern.
Misting the asparagus fern can help maintain the necessary humidity levels.
Whether that’s grey or yellowing leaves or leggy, listless growth – I have heard it all.
So, let’s dispel some myths and propel some cold, hard truths.
Light
Asparagus setaceus thrives in bright, indirect light. This means a bright room, but not sunbeams hitting the plant directly.
It can tolerate some direct sunlight, but too much can cause the leaves to turn yellow and drop off.
The ideal location is near a window with sheer curtains that diffuse the light, protecting the fern from the harsh afternoon sun.
Temperature
This plant prefers cooler temperatures and does well in environments that are consistently between 18°C to 24°C (65°F to 75°F).
It should be protected from drastic temperature changes and kept away from direct heat sources like radiators and from drafty windows during the colder months.
Humidity
Asparagus setaceus enjoys high humidity, which mimics its native tropical environment.
In dry indoor environments, particularly during winter when heating systems are in use, humidity can be increased by misting the plant regularly, using a humidifier, or placing the plant's pot on a tray filled with pebbles and water (ensuring the bottom of the pot isn’t sitting in water).
Watering
Watering should be done regularly, keeping the soil consistently moist but not soggy.
Allow the top inch of the soil to dry out slightly before watering again.
Overwatering can lead to root rot, so ensuring the pot has good drainage is important.
During the winter, reduce watering slightly as the plant’s growth slows down.
For use in your substrate; coco coir is an ideal alternative to peat moss.
Soil
Asparagus setaceus prefers well-draining, nutrient-rich soil. A good potting mix would include components like coco coir, perlite, and organic matter (such as worm castings), which help retain moisture while allowing excess water to drain away effectively.
The soil should be slightly acidic to neutral in pH.
Regularly refreshing or topping up the soil can help maintain its structure and fertility.
Now, let’s kick it up a notch, shall we?
1.4 | Advanced Care for the Asparagus Fern
As your Asparagus fern grows, you’ll need some higher-level care advice.
Read on to discover how best to maintain your plant pal long-term:
Like most houseplants, the Asparagus fern benefits from occasional pruning.
Pruning the Asparagus fern
Asparagus setaceus benefits from regular pruning to keep it in shape and encourage fuller growth. Prune in the spring before the growth period.
Use clean, sharp scissors or pruning shears to cut back excessively long stems or remove yellow or dead foliage.
This keeps your plant looking tidy and encourages new, denser foliage to form.
Repotting the Asparagus fern
When your Asparagus setaceus starts to look a bit cramped in its current pot, or you notice roots poking out of the drainage holes, it's time to consider repotting.
The best time to repot is in the spring. Choose a pot one size larger than the current one and fill it with fresh potting mix.
Carefully remove the plant from the old pot, untangle any circled roots, and place it in the new pot. Backfill with soil and water thoroughly and place the plant back in its preferred spot.
Propagating the Asparagus fern
The Asparagus fern is simple to propagate.
Pop the plant out of its pot and pinch off the soil, and you should be able to see where the stems can be separated from one another.
Separate the stems separately or in clusters, and plant these in other pots or terrariums as per the guidance in this article.
Worm castings are a great choice for fertilisation
Fertilization for Asparagus ferns
Feed your Asparagus setaceus with a balanced liquid fertilizer every few weeks during the growing season (spring to early fall).
Reduce feeding in winter when the plant's growth naturally slows down.
Always follow the recommended dilution rates on the fertilizer package to prevent over-fertilization, which can harm the plant.
This wraps up just about all the info you’ll need to get the most from your Asparagus fern – but let’s quickly look at some safety concerns.
1.5 | Is the Asparagus fern safe for pets?
I didn't have any images of the Asparagus fern next to animals so I spent 12 hours crafting this masterpiece
One of the most frequent questions we get asked by customers in our shop is if this or that plant is safe if consumed by an animal.
So, I do understand just how important getting this right is.
Pets
Asparagus setaceus can be mildly toxic to pets if ingested.
It contains sapogenins that can cause stomach upset, vomiting, and diarrhoea in cats and dogs.
Keeping this plant out of reach is wise if you have curious pets prone to nibbling on houseplants.
Other animals
Like household pets, Asparagus setaceus may also pose a risk to other animals.
While not highly toxic, it's best to prevent access to the plant to avoid any risk of digestive upset or other mild toxic reactions.
People
For humans, Asparagus setaceus is generally considered safe to handle.
However, it can cause skin irritation or an allergic reaction in some individuals, particularly those with sensitive skin or known allergies.
While not toxic if touched, care should be taken to wash hands after handling to avoid potential irritation.
Ingestion, particularly of the berries, should be avoided as it can cause gastrointestinal discomfort.
2 | Terrariums and Asparagus Ferns
Using a small asparagus fern for one of our terrariums.
Although it is a stunning houseplant, I get the most joy from the Asparagus fern when using it in my terrarium designs.
There are, in my mind, two typical types of terrariums:
Botanic: Botanic terrariums focus largely on the inclusion of the plants themselves – perhaps particularly on colour or general placement.
Scenic: Scenic terrariums aim to capture a scene in scale – a miniaturised landscape shrunken down to fit into a tropical terrarium.
Now, the Asparagus setaceus and Asparagus plumosus are both excellent additions to either style, especially the scenic terrarium.
Their tree-like fronds are perfect for recreating the canopy of a rainforest or the towering ferns of the Jurassic period.
Discover essential tips in our complete beginner’s guide to setting up your first terrarium with Asparagus ferns.
2.1 | Why you should use Asparagus ferns in your terrariums.
Beyond the above, there are plenty of reasons why the Asparagus fern family make for wonderful additions to any terrarium:
- Scenic sidekicks: As mentioned above, the Asparagus fern brilliantly complements a to-scale viewing experience for a scenic terrarium. The thin stems and looming leaves create the effect of a rainforest tree.
- The height advantage: The towering growth of the Asparagus fern gives you an option when you need verticality in your design to help increase depth and texture.
- Shadow caster: Asparagus setaceus and Asparagus plumosus have looming fronds that cast shadows upon the rest of your terrarium. Shadows enhance the colour of your designs and make spaces look less flat.
- Ease of care: Due to the terrarium's self-regulating nature, Asparagus ferns become very low maintenance compared to inside a container. Just ensure that the light levels are on the indirect side.
- Ideal conditions: As humidity-loving tropical plants – you’ve got the perfect choice for most terrarium set-ups in the palm of your hand.
Many of these points speak to how strongly Asparagus ferns complement other terrarium plants.
Spot the Asparagus fern
Admittedly – they don’t work very well on their own; things can look a little sparse.
Next, I’ll give you some of the plants I think pair perfectly with the Asparagus ferns.
2.2 | Plants to pair with Asparagus spp.
Pairing the right plants together isn’t always easy. I have written extensively about my favourite plants to use in a terrarium overall.
But, if you are creating a scenic terrarium, opting for smaller leave plants that are thus more visually adaptive is important.
Here are my top three plants to pair with Asparagus fern:
Pilea glauca/Pilea libenensis
Pilea libanensis, also known as the Silver Sprinkles plant, is a delightful, compact houseplant with a cascade of tiny, round, and shimmering silver-green leaves.
I like to take rootless cuttings of this Pilea just above their nodes. This way, I am left with tons of little flower-like cuttings that can be nestled between moss pieces.
This is another fantastic scenic-style plant for your terrariums. The small leaves help develop a sense of scale.
Nephrolepis exaltata
I will often recommend pairing like with like.
Now, as mentioned, the Asparagus fern is technically not a fern.
But visually, their fluffiness complements the fronds of more traditional, official ferns such as the Nephrolepis exaltata.
Additionally, you’ll get the juxtaposition in height from your Nephrolepis, creating more verticality and depth in your terrarium.
Learn more about the Boston fern.
Peperomia rotundifolia
Like the Pilea libanensis, the Peperomia rotundifolia allows for simple, rootless cutting propagation, useful for creating miniature scenes.
The difference is the look of the leaves:
They’re bigger and brighter, which brings more light to your terrarium and creates strong variation against your Asparagus fern, which has a darker green hue.
2.3 | How to Use an Asparagus Fern in Your Terrarium
Arching fronds create shadow and thus depth inside a terrarium.
I want to give you a quick project to try in your next project if you’ve managed to get your hands on an Asparagus setaceus or Asparagus plumosus plant.
The Asparagus fern is best used as a complimentary plant to give your terrarium a richer, fuller look.
So, in your next terrarium, try following our propagation advice to split the plant into cuttings.
Next, place the shorter stems into the foreground of your terrarium.
Take the taller stems and plant them at the rear of your terrarium.
Asparagus ferns are quite springy, so you might need to trim off an inch to allow for proper planting.
Next, place pieces of cushion moss around the base of your stems and nestle some rootless cuttings of Pilea libanensis inside them.
Fill the rest of your terrarium with shorter ferns and hardscape elements such as Dragon Stone or driftwood.
You could even use the hardscape elements to create a feature such as a bridge or cave – through which the Asparagus fern will do its best work.
Placing larger pieces of your Asparagus fern at the rear of your terrarium with shorter pieces at the front creates a verticality that will increase the visibility of your design.
The clumps of moss and Pilea libanensis will add to your sense of scale, especially if you’re using hardscape elements to create a feature.
3 | More on the Asparagus Fern
3.1 | Troubleshooting and FAQs
Before we finish, let’s examine the questions I am most often asked about Asparagus setaceus and Asparagus plumosus.
I’ve included as much as I could think of, but if you have more questions, please drop them down below!
What light conditions are ideal for Asparagus setaceus?
It thrives in bright, indirect light but can tolerate partial shade. Personally, I’ve experienced yellowing when the fern is exposed to higher levels of sunlight.
How often should I water my Asparagus setaceus?
Water when the top inch of soil is dry; keep the soil consistently moist. Don’t allow the plant to fully dry out.
What is the best soil mix for Asparagus setaceus?
A well-draining mix with organic matter, like a blend of potting soil, perlite, and compost. At ome, we use our own tropical substrate mix which comprises of orchid bark, coco coir, worm castings and black sand.
Can Asparagus setaceus be grown in low-light areas?
It can adapt to low light but may grow less vigorously.
How do I prune an Asparagus setaceus?
Trim back the stems to maintain shape and encourage fuller growth, ideally during the spring. You can trim dead leaves, but if your entire stem is starting to grey/yellow – I would recommend trimming the entire stem from the base.
Is Asparagus setaceus suitable for terrariums?
Yes, its humidity preferences and delicate foliage make it a great terrarium plant. It is one of my favourites and, from what I can tell on our Instagram, one of the most sought-after terrarium plants.
How can I increase humidity for my Asparagus setaceus?
Regular misting, using a humidifier, or placing the pot on a tray with water and pebbles. I like to keep my Asparagus ferns in terrariums or in the bathroom to guarantee high humidity.
Otherwise, you can also use a plant mister.
What fertiliser should I use for Asparagus setaceus?
A balanced, liquid fertiliser diluted to half-strength during the growing season. Inside the soil, there should be some form of fertiliser such as worm castings.
Why are the leaves on my Asparagus setaceus turning yellow?
Yellowing can occur due to overwatering, nutrient deficiencies, or too much/too little light. In my experience, too much light is the most common cause of yellowing leaves.
How do I re-pot an Asparagus setaceus?
Carefully transfer the plant into a slightly larger pot with fresh soil, avoiding damage to the roots in the process.
How do I propagate Asparagus setaceus?
Propagate by cutting stem pieces or dividing at the root during repotting. The stems should easily separate out for easy splitting into separate projects.
What are some creative ways to display Asparagus setaceus?
Use in hanging baskets, as a standalone plant on a bookshelf, or as underplanting for larger indoor plants. I sometimes incorporate Asparagus ferns into open planter projects, as well as closed terrariums.
How do I treat pest infestations on Asparagus setaceus?
Remove affected areas and treat the plant with insecticidal soap or neem oil. I haven’t found the Asparagus fern to be particularly susceptible to pests, other than Fungus gnats – which are best treated with the use of yellow sticky pads.
What companion plants pair well with Asparagus setaceus in a terrarium?
Mosses, small ferns, and creeping plants like Ficus pumila. Alternatively, I would recommend to-scale plants such as Pilea libanensis or Peperomia rotundifolia. This will help achieve a sense of scale.
Read our guide on the top plants for terrariums.
What temperatures are too cold for Asparagus setaceus?
Avoid temperatures below 10°C (50°F) as it prefers warmer climates. To be completely honest, I have kept the Asparagus fern in cooler conditions (about 8°C) but this is best avoided.
What should I do if the stems of my Asparagus setaceus become leggy?
Increase light exposure and prune back to encourage bushier growth. See the advice above for pruning tips!
Is Asparagus setaceus safe for pets?
It can be mildly toxic if ingested, so it's best kept out of reach of pets or young children.
How fast does Asparagus setaceus grow and how big can it get?
It's a fast grower; with proper care, it can reach several feet in length!
Can Asparagus setaceus be used in a bioactive terrarium setup?
It can be incorporated into bioactive setups, playing a role in the ecosystem as ground cover that helps maintain humidity levels.
How does Asparagus setaceus respond to artificial grow lights?
It generally responds well to grow lights, especially if they’re full spectrum, making it a good candidate for less naturally lit spaces. Be careful, though, as too much light can scorch the leaves.
What's the impact of fluoride in tap water on Asparagus setaceus?
Fluoride-sensitive Asparagus setaceus may develop leaf tip burn. Use filtered/distilled water or rainwater to mitigate this risk.
Are there any interesting historical uses of Asparagus setaceus?
Historically, not specifically for Asparagus setaceus, but its relative, the edible asparagus, was prized in ancient times for its medicinal properties.
3.2 | Where to buy Asparagus ferns
If you're in the UK, you're in luck! We have Asparagus ferns for sale online, ready for next day shipping.
If you're further afield, browse available Asparagus ferns in your area.
4 | Conclusion
And that concludes our guide on the Asparagus fern.
It’s a gorgeous, versatile plant that can thrive as a houseplant – but shines inside terrariums.
Try some of the above tips, but if you need more help or have any suggestions or tips, we’d love to hear from you. The comment box is just below.
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