The Ultimate Stromanthe Triostar Care Guide

There's a LOT to love about the Stromanthe Triostar. Pink, variegated and less of a drama queen compared to others in the Prayer Plant family (called Marantaceae). Not exactly easy care, but not (too) difficult either, once you know what they love (and what to avoid). Find out below how to give them the care they need, what not to do, and how to fix common Stromanthe issues...

Can the real Stromanthe please stand up?

This gorgeous plant has some identity issues. 'Stromanthe Triostar' is the correct common name, but 'Tricolour' is often incorrectly used. The botanical name is Stromanthe sanguinea 'Triostar'. However this is NOT the same plant as the Ctenanthe oppenheimiana 'Tricolour'. Once you know what to look for it becomes obvious which one you have. If you're not sure, you can check the differences between Stromanthe Triostar and Ctenanthe Tricolour here > 

Although Calathea and Stromanthe ARE relations from the same Maranta family, Stromanthe Triostar is NOT a Calathea, and Calathea Tricolour or Calathea Triostar don't exist!  

 

Ctenanthe (left) and Stromanthe (right) showing one of the most obvious differences. On the Ctenanthe Tricolour (left), the line down the middle of the leaf (the midrib), is a clean 'pin-stripe' - and on the Stromanthe Triostar (right) you can see a blurred 'glow' either side of the midrib.

 

What temperature does Stromanthe Triostar prefer?

Like me, these plants are not a fan of the cold. Although Stromanthe tend to be more cold tolerant than other prayer plants, aim for above 15 degrees Celsius (60 degrees Fahrenheit) overnight, and ideally between 18 to 27° C / 66 to 84° F during the day. Although they can put up with down to 10° C / 50° F provided all other conditions are great, I wouldn't risk it myself. 

Stromanthe are native to the Amazon rainforest in Brazil. Found growing in the understory as an upright perennial. Unlike an annual plant, perennials can live for years. Even if some of their growth dies back in poor conditions they can put out new growth when conditions improve. Although the Amazon has consistently warm, humid conditions all year round, it's hard to provide that consistency in our homes. So if you do find your Stromanthe kicks up a fuss and dies back a bit, don't give up! They can be saved. 

The Amazon rainforest averages 25° C / 80° F all year round, even in winter. So unless you're blessed with mild winter temperatures, you'll likely need artificial heating to keep the house warm enough for your Stromanthe in winter. 

BUT keep in mind most artificial heat sources also dry out the air. So watch out for signs of low humidity like moisture withdrawing from the tips and edges of leaves and leaves curling inwards. Before you worry and invest in a humidifier, get a cheap hygrometer first to check humidity levels as there are other reasons your Stromanthe might show those same symptoms, like chlorine toxicity, fertiliser burn and under-watering. More about those coming up. 

 

What lighting do Stromanthe Triostar need?

Being an rainforest understory plant in the wild, Stromanthe prefer bright indirect light.  I'd recommend avoiding direct sunlight even indoors, as their thin, variegated leaves are more prone to scorching. As far as variegation goes, in my experience more light does NOT mean more pink, but less light does mean more green.  I do give my pinker, more variegated Stromanthe more light since less green means less ability to photosynthesize and grow.  

Like other prayer plants, Stromanthe move their leaves a lot! I love this about them. Towards then away from the light during the day, and sometimes folded up at night, exposing those hot pink undersides.

Leaves can also move in response to water and temperature, such as curling inwards to preserve water when they're too dry or hot. I find the less compact your Stromanthe is, the more dramatic the movement is.

Curling inwards is typically a sign of something moisture-related being wrong, such as under-watering or low humidity. Whereas leaves curling outwards is more often a sign of over-watering or even the dreaded root rot. How to check for and treat root rot >

 

What potting mix is best for Stromanthe Triostar? 

In general you want a light, airy mix with plenty of air pockets, that offers medium to high water retention to help avoid your Stromanthe fully drying out. It can be a hard balance to nail, as substrates that retain water also tend to be finer and more likely to compact when wet, meaning root rot can come knocking.

After trying a lot of different mixes I've ended up finding my favourite for my Stromanthe is the Bio Leaf African Violet Mix. It's light and fluffy but holds water for longer. Being an under-waterer myself it's perfect for my plant parent style.

However, if you're more the over-watering type, or substrates take longer in general to dry out in your conditions, I'd go for half Bio Leaf African Violet Mix and half soil-free aroid mix, like Bio Leaf Indoor Fine/Medium. 

If the mix you choose hasn't got the balance right, you can adjust other conditions to make it work. Water more or less often, provide more or less light, warmth and airflow. More warmth, airflow and light all help plants use up excess moisture in their soil faster to help prevent root rot.

Or in a mix that doesn't hold enough water or dries out quickly, both watering more often and making sure to water heavily enough so the entire substrate is saturated will help. Higher humidity also helps Stromanthe cope with drier conditions. 

I'm a fan of bottom-watering for my Stromanthe for that reason, and I give them a good 'bath' leaving them to soak for a while to help make sure no roots miss out. Or you can repot into a substrate better suited to Stromanthe's needs for staying lightly, evenly moist and never fully drying out. 

Make your own Stromanthe substrate

If you prefer to DIY your own mix for your Stromanthe, start with:

• 1 to 2 parts peat moss or coco coir
• 1 part perlite
• 1 part potting mix
• 1/2 part of charcoal
• 1/2 part vermiculite

Adjust your levels from there to create a mix that matches your conditions and watering habits. 

 

When should Stromanthe Triostar be repotted? 

When you bring a new Stromanthe home, I prefer not to repot for at least 4 weeks unless the substrate is really bad and refuses to dry out. Even if rootbound I would not repot for a while and just let it settle in first.

I find Stromanthe need a little extra TLC when you change their conditions, and adding the stress of repotting on top of coping with a change in conditions could be too much.

Stromanthe can be shockers for throwing a wobbly when their conditions change, so just baby them a bit at first and they should come right within a week or two. Best to start with a nice warm spot with bright, indirect light, and let them settle in there for a few weeks first, before changing anything.

They may sulk at first with either closed up or drooping leaves but warmth and light should see them come right quickly. Stromanthe tend to be more prone to transplant stress after repotting too, so I use this method when repotting mine: What to do (and what not to do) when repotting >

 

What are the watering needs for the Stromanthe Triostar? 

Aim to maintain your Stromanthe lightly, evenly moist and avoid them ever fully drying out. Definitely avoid wet feet or soggy soil or you'll risk the dreaded root rot. Don't leave them sitting in water, especially if it's water that's drained through the substrate, as drained water has a higher concentration of mineral salts from water and fertiliser which can burn roots and leaves.

If you don't have a clear pot to help judge moisture level, or aren't confident about when to water, grab a moisture meter which changes colour depending on the water level below the surface. I like the Crew Soil Sensor or the PlantDoc Moisture Meter.

Beware under-watering

Stromanthe often get under-watered for fear of root rot, however this instead causes dry, crispy leaf tips and edges. Another sign you've left it too long between watering is leaves that curl inwards to try to conserve water. They really don't like to fully dry out (although if humidity is high they handle drying out much better).

When to water Stromanthe 

I water again when the potting mix is about 3/4 dry. Shifting to clear pots makes it really easy to see the water level, as water droplets condense on the inside, showing you where the water level is down to. 

Water more often when growing, at warmer times of year, when the air is dry, and in brighter conditions or when airflow is higher. If you pick a good potting mix it helps retain air pockets even when wet, making it difficult to over-water and reducing the risk of root rot.

Water less often in winter, when it's colder or darker, when airflow is low or humidity is low and the air is drier. Since so many factors come into when to water, you really can only judge based on your plant in your conditions. Watering on a schedule isn't possible. 

Watch out: Chlorine can be toxic for Stromanthe

Stromanthe and prayer plants in general are on the list of plants more sensitive to chlorine. Excess chlorine can burn roots, prevent them properly absorbing water for the plant, cause burned, dry, brown leaf tips and scorched leaf edges, even yellowing and leaf drop.

Ways to remove chlorine from tap water

You can use rainwater or buy bottled water. You can also leave tap water in open containers (ideally in the sun), for 2 to 4 days and wait for the chlorine to gas off into the air. Use a chlorine test strip to check the chlorine's gone before you water. How much chlorine is in your water changes how many days it takes for chlorine to gas off.

You can also use a Brita water filter which filters about a litre of water in 15 minutes and works out around 6 cents a litre (a $10 filter cartridge filters about 150 litres). Or what I use are Plant Water Drops which instantly removes chlorine from tap water at a cost of about 3 cents per litre. A faster, easier, cheaper, simpler solution if the other options aren't realistic for you. 

Should you top water or bottom water Stromanthe?

 

Although top watering is better for most plants for a few reasons, my Stromanthe are plants I prefer to bottom water so I can make sure the entire substrate gets saturated and none of those delicate roots miss out.

BUT I still do a regular top water flush with plain water (water with no fertiliser added), every 2 to 3 months. That helps flush out build-up of mineral salts from tap water and fertiliser that can otherwise burn roots and leaves. Bottom watering doesn't help protect from fertiliser and mineral burn like top watering does. You can also use a low-salt fertiliser like GT is smart for Stromanthe to further reduce the risk of fertiliser burn (more coming up about fertiliser).

Their root system sends out fine, delicate roots everywhere, so whether you top water or bottom water, make sure the entire potting mix is evenly saturated so all roots get both the water and minerals they need. This will NOT increase the risk of root rot. When top watering, water heavily enough so water pours out the bottom of the pot to help flush out any excess salts.

Let your Stromanthe fully drain before returning to the saucer or cover pot. Drained water is higher in salts and you don't want your Stromanthe absorbing those back up again. If you do water into a saucer or cover pot, I'd remove any drained water after about 15 minutes. The potting mix should be still be saturated enough not to re-absorb the salts.

Does water temperature matter?

Yes, like the rest of your indoor jungle, you should avoid cold water for Stromanthe. It can 'shock' and damage roots. The ideal temperature is around 20 degrees. At this temperature the water still contains a lot of oxygen, and it is the ideal temperature for roots to get to work pumping that fresh water and essential minerals around the plant. Cold water reduces water flow and hot water reduces oxygen. Too cold or too hot can both shock and damage roots. 

 

Are Stromanthe Triostar pet safe? 

Yes! It feels so nice to say yes for once to this question since so many indoor plants are not pet safe but yes, Stromanthe are pet safe and non toxic to animals and humans.

 

Stromanthe Triostar pro tips & problem solving

Keeping a Stromanthe alive isn't difficult, but keeping her looking good can be. If the conditions aren't great, those lovely variegated areas can quickly turn yellow or brown, and leaf tips and edges can go crispy or curl up. Here are the most common Stromanthe Triostar issues and how to solve them.

 

Why does my Stromanthe Triostar have brown crispy leaf edges and dry leaf tips?

Humidity is your friend! You want to maintain humidity at least above 60% for Stromanthe to be their happiest, best-looking selves. But if other conditions are good, I find mine are fine even at lower levels and I try to maintain them above 40%.

Provided you're NOT underwatering, you ARE using chlorine-free water, and you avoid them going completely dry between watering, then brown or crispy tips or edges is a common sign your Stromanthe needs more humidity.

Keep in mind brown leaf tips and leaf margins can also be due to chlorine, fertiliser, dry roots and more, so I'd hold off on getting a humidifier while you rule out the common causes first. Getting a cheap hygrometer is a good idea to see what your current humidity levels are first. Low humidity is rarely an issue in a typically humid NZ summer, but a humidifier in winter can be needed since most heating dries out the air. 

 

Why does my Stromanthe Triostar have yellow leaves?

Like most plant drama, yellow leaves could be a sign of a few different things, but with the Stromanthe I find it typically relates to water. Most often from over-watering or inconsistent watering due to letting them go too dry too long between watering. Both under- and over-watering can cause root rot and yellowing lower leaves in particular is a warning sign something may be going wrong under the surface with the roots.

A water-related cause isn't the only culprit for yellow leaves. For help diagnosing and fixing all the common causes see Help! Why are my plant's leaves turning yellow? >

What is the best fertiliser for Stromanthe Triostar?

Definitely DO fertilise your Stromanthe Triostar. Stromanthe are light feeders, but that doesn't mean no food at all! Look for a complete and balanced NPK fertiliser that provides all 12 essential minerals. Ideally one formulated for indoor plants.

Because Stromanthe are more sensitive, a fertiliser that's free of chlorine, sodium and chlorides is an added bonus. Those are common ingredients in most fertilisers and not that big of a deal unless you have a more sensitive plant like Stromanthe.

The Weakly Weekly method is superb for Stromanthe no matter what fertiliser you use, where you feed lightly, every time you water, which both reduces the risk of deficiencies while also protecting from fertiliser-burn.

I've tried a lot of fertilisers over the years and have a couple that top of my list for my Stromanthe and other more sensitive plants. I like the GT range in general, in particular their GT Foliage Focus, and find Plant Runner's Indoor Plant Food is great also. Both are higher-nitrogen foliage fertilisers.  
 

Why do my Stromanthe Triostar leaves have 'wet patches'?

This freaked me out the first time it happened to mine. See that darker pink patch below? at the bottom of the front leaf? That's the Stromanthe version of oedema, also spelled edema. It can show differently in different leaf types. Normally caused by the roots trying to get rid of excess water, more than it can 'breathe out' like it would normally. Edema can cause leaf cells to burst or flood with water and the leaf to change colour and becoming transparent. 

If you see it happening to yours, this is why edema happens, how to fix it and prevent it happening again >
 

Photo from Behnke Nurseries:

Once your new Stromanthe has settled in, they should become much easier care. Some will keep up those drama queen tendencies and be determined to die back no matter what you do, in which case Stromanthe might just not suit your conditions or plant parent style, but I hope this ultimate care guide has given you and your Stromanthe everything needed to be happier and healthier without the drama.