String of Pearls, or Senecio rowleyanus, are one of the absolute most popular succulents out there. They’re extremely distinct, and even people who aren’t super familiar with succulents, houseplants, or greenand growing things in general would probably recognize them.
Unfortunately for the plants and the people who Just Have To Have Them, they aren’t actually the bomb-proof houseplant that Pinterest or random Instagram accounts would have you believe. If you’ve already tried your hand at growing a few of these, and failed, you’re far, far from alone. Most people (myself included) killed their first String of Pearls, and maybe even a few more after that. Luckily, once you do get the care dialed in, you’ll discover that they are in fact quite easy to grow. It’s understanding what they actually need that tends to trip people up.
Why do people struggle with String of Pearls so much? Probably lighting.
The first mistake that seems to happen for folks trying to grow String of Pearls is usually related to light. They’re not house plants, they are succulents, and need light like a succulent.
Trying to grow them inside? They need to be in lighting conditions as bright, if not brighter than, what you’d grow a large monstera or fiddle leaf fig tree with. If you’ve struggled to grow succulents indoors and thought String of Pearls would be easier, you were wrong. Indoors, they need extremely bright light, preferably near a south facing window. Use a light meter or a light meter app to find a spot that gets pretty consistently about 400 – 500 foot candles for most of the day. Alternatively, if your window gets 1000+ for an hour or two in the morning, and then it dips down to the low 100 – 200 range, that might work.
Don’t have a spot that’s that bright? Your string of pearls is unlikely to thrive, plain and simple.
You might see them in photos or magazines in spots that are very clearly not by a window, or in an area that gets a lot of light, and a very important thing to remember about these images is that they are staged for the photos. Just like the furniture and artfully placed humans lounging on said furniture, the plants don’t exist there all the time.
Outdoors, you’ll have an easier time with these, mostly. If you’re in an area warm enough for them year round, place them somewhere that gets an hour or two of morning light (at least) and shade the rest of the day. With patience, you can get them acclimated to significantly more sun, although they won’t be as green and plump. I have a bundle that I forgot about sitting out in an area where I have my aloes for sun stress, and while the pearls aren’t exactly happy about their circumstances, they survived.
They tend to look their best with at least an hour or so of morning sun, up to 3 or 4 hours, and then shade from about noon onward. They’ll grow nice, even strings with nice round leaf bodies.
A pot of very sad, half-dehydrated, and tanned pearls that I had forgotten next to my aloes for several months. Not dead, but definitely sad.
The other challenge people face: water (which is closely related to soil)
Like I just said, the string of pearls is a succulent.
That means they need the same low levels of water as a succulent would.
That also means that if you have them indoors, their water needs will be quite drastically less than you’d expect. I’m talking watering once a month in winter, maybe every couple weeks in summer. While propagating these, I have had pots that I completely forgot existed do amazing in a sheltered but sunny spot.
If you have a good, well draining soil mix that dries out appropriately quickly, my recommendation for watering completely flips: water these guys as much as they’ll take any time the soil is dry. For my outdoor pots, that’s about once a week in winter, and almost daily in summer. They grow like GANGBUSTERS that way!
String of Pearls can be pretty thirsty for succulents, but that’s only if they’re getting adequate light for growth. In a dense soil blend, such as the soil they likely came from at the nursery, or if you’re using a Miracle Grow type mix, the soil doesn’t dry out all that quickly. While the top layer might be bone dry to the touch, if you lift up the pot and look underneath, I’d bet you that the bottom layer of soil is still wet. I see it all the time thanks to how often I’m unpotting these to remove their soil and pack them for shipping: the dense nursery soil just doesn’t dry out all that fast. The top 1/2 of the soil might be dry enough to be a rock, but when I lift the plant out of the pot, SURPRISE: the bottom half is still damp.
Since the bottom is still damp, the top doesn’t need more water – the plants’ roots will go down and drink up.
However, when you repot your succulent String of Pearls into an airier, lighter mix that’s blended with perlite and/or pumice in addition to the organic matter, the soil is lighter and easier for the plants’ roots to go through. It’s more similar to their natural growing environment (Southwest Africa), and means they are able to just plain grow better. “Grow better” = take sunlight and water and convert that into energy, which means more leaves, more length, and that dreamy trailing plant that you have been ogling on Pinterest for ages.
So for beautiful string of pearls, their roots need a light, porous soil that they can dig into, absorb water from readily, and be thirsty and ready for more in a matter of days.
If you’re growing your string of pearls indoors, try upping the amount of perlite you mix into the soil to close to a whopping half of the soil blend. If you’re a heavy handed waterer, they should dry out fairly quick with a blend that heavy in inorganic matter. Otherwise, mix the soil as about 1/3 pumice or perlite, and 2/3 soil, and you should be golden.
A pot of pearls I started at the beginning of winter showing the beginnings of new growth at the edge of some strands.
Other General Guidance and Myths
Lies people tell about Senecio rowleyanus include, but are not limited to, “they have weak, shallow root systems” and “they sunburn easily” and “they need to be kept warm all the time”.
Weak, shallow root systems:
This one is probably because people don’t unpot/handle roots as often as folks who ship these guys bare roots, so you don’t see the rather extensive, vigorous, and determined root systems these guys get when they’re happy. Just because the main roots of the plant can go into relatively small pots, doesn’t mean they are lacking in solid roots. When potted correctly, with a porous soil that dries quickly and given appropriate light, these will develop a solid set of roots that wedge themselves into anything. I’ve had to pry the roots out of neighboring pots, the cracks in their own pots, and one time even the siding of the house. They are determined.
That doesn’t mean stick your 4″ pot of pearls in a 6″ azalea pot; it just means that your typical succulent pot that tends to be shallower will work fine. It also means that if you want to try and stick them in a tall narrow pot for DrAmAtIC eFfEcT, you can, but just be aware you’ll need a super porous blend to allow for the roots to crawl down and absorb moisture appropriately.
This is usually because when you bring these straight home from a nursery, you’re taking them from the sheltered, idealistic growing conditions they were propagated in to your harsh, unyeilding home with its blazing sun. I can’t have these out unprotected without slowly acclimating them to more intense levels of sun, and even then, these definitely prefer more shade than most succulents.
That being said, I’ve also seen these growing as a goddamn carpet underneath cactus benches at nurseries, just with a bit of a tan.
Don’t mistake the brown blushing they develop in intense sun for actual sunburn. I talk about actual sunburn here. When your String of Pearls get sunburnt, they will turn a crispy yellow-white, sometimes a mushy brown, but never the dusted brown/red that a sun-hardened senecio will turn. If your string of pearls are just darker than what you see online, it’s literally just a tan. You might want to move them to somewhere a little shadier during the afternoon if you want them to be nice and green, but the brownish coloration is just the plant protecting itself from the sun. The carpet of string of pearls I saw at a cactus nursery was pretty much entirely brown rather than green due to the amount of sunshine they were exposed to.
Keep warm (room temp) all the time:
The string of pearls I leave exposed to 30F weather on the regular would like to have words with the people who say this. I will say that unless they are quite bone dry when nighttime temps hit the mid 30s, they will definitely rot right out.
If your weather is cold but you don’t get hard frosts, these are just fine with night time drops to the low 30s if you let their soil dry out. The dry soil is key: in their natural environment, these plants only experience temperatures that low during their dry season. When it’s cold, they’re somewhat dormant, and that’s why you need to keep them dry – they won’t be absorbing or using any water, and the longer their roots sit in the wet, the more likely they are to rot.
Basic String of Pearls Care
Plant your string of pearls in a pot only a little bigger than the pot size you bought it as. If you got it as a 2.5″ pot, moving up to a 4″ works, but you may need to propagate additional strands to fill the pot. The plants won’t fill out at their base – they just get longer, not fuller, so if you want a big full pot, you’ll have to fill it with a couple smaller plants or get a bigger plant to begin with.
Use a succulent mix as the soil. Most standard “big bag” mixes you’ll want to mix with about 1/4 to 1/3 additional pumice or perlite for drainage, but if you’re using a smaller bagged blend such as Bonsai Jack or whatever is on Amazon these days, those are probably already mixed with more porous material. I don’t personally use those blends, and tend to mix my own, so you’ll need to use your judgement with that. If the soil has lots of pumice and big chunks in it already, you probably don’t need to add much to keep it aerated.
Make sure you pot the pearls so that they are pretty much flush with the top of the pot – you don’t want them to be sunk in significantly. Something about being sunk in seems to lend itself to rotting out the stems or pearl leaf bodies, so you’ll want them to be pretty much flat with the upper edge of your pot.
Water sparingly. When you first pot up your pearls, give them a good soaking, and then after that lift up and check under the bottom of the pot to see if it’s dry all the way through before watering again. If you’re finding that the bottom stays wet looking even as the pearls start to wrinkle, use a small watering can or cup to only add a small bit of water up top. Give them a light splash, just enough to see the soil get damp, then check the pearls the next day to see if they’ve plumped up. If not, water again.
Alternatively, you can go the nursery route, which is to water from the top until the water is flowing straight out the bottom, which works well if you are letting your pearls get dry enough to start to wrinkle or prune. If you flush the soil thoroughly this way, you can get by with the bottom never fully being absorbed by the plant; by flushing it, you’re removing the stagnant water before bacteria and other problems creep up. A key element of this method is to let the water truly flow out the bottom. It needs to be a steady stream before you stop watering up top, and the weather needs to be favorable enough for the top of the plant to dry out by the end of the day.
When in doubt, water less. String of Pearls can get downright raisin shaped before they actually die, and being left to get a bit pruny is far better for them than being overwatered.
You probably don’t need to fertilize these much, if at all, but if it’s been over a year since you potted your pearls, a couple times a year in spring and/or summer you can fertilize them with a dilute feeding of succulent fertilizer, fish emulsion, and/or worm casting tea. They don’t need much, but a little bit of a boost when the soil starts to get stale can be helpful to encourage growth and blooming.
Keep in an area with plenty of bright, indirect light. For long term growth, I’ve had these do quite well when kept near my Monstera deliciosa plants, in an area with direct morning sun for a couple hours early on, and then shade for the rest of the day. They are in a spot they share with my variegated string of hearts, and in general, that bright but sheltered area works quite well.
Sadly, I don’t have any photos of long, trailing plants to show off because a) I tend to list the 4″ pots once they start to look cool and b) because we have a problem with rats and the little shits like eating my string of pearls.
While wikipedia and the internet like to mention that these are mildly toxic, I’ll note that I’ve never had skin irritation from the sap, and considering how much the local rats like to munch on them, I don’t think the rats find them all that toxic either. Maybe we have super rats? Either way, science-y folks at University of California, Davis, have included these in a list of poisonous garden plants, so try to restrain from eating them.
Do variegated string of pearls need anything special?
Nope. I have mine quite literally next to my regular string of pearls and they’re growing like gangbusters.
I wouldn’t abuse these with increased sun exposure the same way I do to the regular string of pearls, as the variegation means they can’t adapt as readily, but for shady spots the care is the same. You’ll notice mine have a nice layer of pumice on and around them – this is to protect the top and encourage a bit of extra rooting from the nodes of the plant at the top. Is it working? I’m not sure yet, I’ve only had the plant a couple months, but the growth overall has been nice and it seems to be thriving.
So wrapping up: String of Pearls is an easy, but not too easy, plant to grow. They don’t fill the pot they’re in, they like lots of light (but not too much), and generally do well outdoors if your winter temps stay above 32F at night.
I do often have these in stock in my Etsy shop, which you can check here. They sell out quickly, and full disclosure, most of these are plants I’ve picked up from a nursery – not pearls I’ve propagated myself! That being said, usually when I have a 4″ pot, those are plants I’ve had myself for a while and are well established.
Enjoy your string of pearls, and if you have care questions, let me know on Instagram @TrexPlants!