There’s no indoor plant quite as cheerful and easy to love as the String of Pearls (Senecio rowleyanus).
These sun-loving succulents thrive in bright conditions – but how bright is bright? And is it possible to have too much of a good thing?
The string of Pearls needs between six to eight hours of bright light a day and will thrive with a few hours of direct sun in addition. Put them in a bright sunny window and they will reward you with ample strings of plump round pearls.
What kind of light does a String of Pearls need?
The String of Pearls is a desert plant. Its native range is arid parts of South Africa, where it forms dense mats along the ground.
As an indoor plant, it adapts well to training from baskets, but it still needs the same sort of sun exposure it would find in its homeland.
To work out the best position for your String of Pearls, you have to consider how much direct sunlight it needs, the direction of light in your home, and how bright that light actually is.
Let’s take a closer look at how these factors work!
Exposure to Sunlight
Your String of Pearls adores bright light. It, like most succulents, is perfectly adapted to take advantage of light levels that would be too intense for other indoor plants.
It’s an excellent choice for areas of your home that would be overrun by a more delicate species.
Most succulents benefit from a few hours of direct sunlight as well.
While your String of Pearls will do fine in constant bright light, it will benefit from an hour or two of direct sunlight as well.
After all, it is well adapted to making the most of that bright light, and unlike most plants, it will not suffer any negative consequences from a few hours of sun-baking.
The Direction of the Sun
Not all sunlight is created equal. The light at dawn is the gentlest, and the light at noon is the harshest.
In practice, this means that we must consider the aspect of a window or the direction it faces.
A window facing east will receive early morning sun, then little else throughout the day and receive bright direct light in the afternoon, but not much earlier.
South-facing windows receive the most consistent levels of light in most growing environments.
They are the gold standard for indoor plants and an excellent location for a String of Pearls. You will need to water it more often the more sun it gets.
The Intensity of Light
Light loses some of its strength as it passes through windows, curtains, and other obstructions.
Even in a room with a large south-facing window, the light closest to the window will be the strongest, while the light farthest from the window will be the weakest.
Make sure your String of Pearls is close to a light source. It prefers bright light and will thrive near a window.
I prefer to hang my Pearls directly from a curtain rod, where they can soak up the early morning sunbeams.
Do String of Pearls like Sun or Shade?
The String of Pearls has a number of adaptations that make it a true desert survivor, well suited to life in the sun.
Its round, flat leaves are perfectly shaped to hold as much water as possible, preventing dehydration.
And if you look closely at your String of Pearls, you’ll notice a line running down the center of each little leaf.
This tiny gap in the outer leaf, known as an epithelial window, allows light to penetrate deep inside the leaf and reach all of the plant’s green tissue.
While botanists are still figuring out exactly how that window works, common wisdom suggests that it gives the leaf the best chance to use that light for photosynthesis without sacrificing its water-saving shape.
It’s no surprise, then, that the String of Pearls thrives in bright light. A shaded specimen will plod along, but it will not thrive.
Keep this cheerful succulent in a brightly lit area, preferably with regular direct sunlight, to give it the best chance of shining.
Where Should You Place a String of Pearls?
When positioning your String of Pearls, consider the size of your windows and what direction it faces.
I always make sure to check over hands and shade provided by buildings or trees outside, and at a few points in the day, too.
A western window with a big tree nearby won’t reveal its secrets till the afternoon, so take the opportunity to check light levels throughout the day.
There are several methods for determining light levels.
The most common are foot candles (FC), which are the light levels produced by an ideal candle over a foot’s surface area. Here’s a breakdown of common light levels in the home.
| Light Level | Light Intensity (Foot Candle) | Typical Locations in Home |
| Full Sun | Over 1000 fc | Bright south or southwestern facing windows, with no curtains or nearby. shade trees. Sunbeams are visible and easy to track. |
| Bright Indirect Light | 500-1000 fc | Diffuse but bright light. Eastern or western facing windows. Close to sources of direct light, often shaded by outdoor trees or curtains. Strong shadows are cast but with no direct sunbeams. |
| Moderate Light | 100-500 fc | The general light level in a well-lit home. Light is diffuse with weak or no shadows cast. North facing windows, some east or west-facing windows may produce this light level if shaded. |
| Low Light | 25-100 fc | Little natural light, often artificially lit. Far from windows or under shade. |
| Very Low Light | Below 25 fc | Quite dark and must be artificially lit. Small shaded windows or none at all. Not suitable for plants. |
Signs That Your String of Pearls Isn’t Getting Enough Light
Let’s take a look at some of the ways you can tell if your String of Pearls is struggling.
Leggy Growth
When we say a plant is “leggy,” we mean that its growth is concentrated in its stems. In the case of a String of Pearls, this means that your poor treasure has more string than pearls!
Long trailing vines with sparse leaves indicate that your plant requires more light. It is in pain and is attempting to stretch its body towards any light it can find.
Leaning Towards Light Sources
This, like legginess, shows your String of Pearls reaching for what it requires. The strings of your String of Pearls will be concentrated on one side of the plant, twisting towards its light source in this case.
While this indicates that your problem is not as severe as a plant with only strings and no pearls, it does indicate that you require more light in your growing area.
String of Pearls Turn White
If your String of Pearls is beginning to resemble its namesake, it’s a sign that you need more light. A pale plant is a weak plant that conserves its resources.
The green pigment in leaves, chlorophyll, is expensive to produce, and a white String of Pearls conserves energy.
No New Growth
In complete darkness, no plant can grow. A String of Pearls that has stopped growing is dying of hunger. It requires light to generate energy and the sugars it requires to survive.
It can survive for a short time on reserves stored in its plump flesh, but those reserves will deplete. Your plant will die if it is not exposed to sunlight.
String of Pearls Drying Up
If your otherwise well-watered String of Pearls starts to shrivel, it’s a sign that the end is near for your poor plant. It shows that the leaves are wilting and starting to die off.
Soil Not Drying Out for Weeks
Water added to potted plants is lost in two ways: through plant use and evaporation. Both processes require light and the heat it generates.
If your String of Pearls sits in soggy soil for weeks at a time, no matter how little water you give it, it tells me you need to move your plant.
Because your plant is not photosynthesizing, it requires little water, and the soil cannot dry on its own.
How to Provide More Light
Fortunately, a lack of light is a simple problem to solve. If your String of Pearls is indicating that it requires more light, simply move it to a brighter location!
Take your time when moving your Pearls to a brighter location. All plants adapt to their light levels, and putting them in a bright spot after a lifetime in the shade can stress them.
It’s like walking out of a movie theater into a bright summer day – quite a shock!
For a few days, I usually move my plants to a light zone halfway between the old and new.
This method will keep your String of Pearls from becoming overwhelmed by its bright new surroundings.
Best Location for String of Pearls
I’ve always loved hanging baskets with String of Pearls plants draped right in front of southern-facing windows.
This provides good, strong light of the best kind, not too strong but warm and embracing.
However, if you do not have good southern-facing windows, think about other well-lit locations.
A windowsill facing east or west may work, as long as it remains bright throughout the day.
Regardless of the angle, make sure your String of Pearls gets a few hours of direct sunlight per day.
In low-light situations, I’ve frequently moved my Pearls outside during the warmer months.
They’ll happily sit on a southern stoop or hang from the eaves of a porch if they’re shaded from the hottest midday sun.
Get a Grow Light & Put Plants Wherever You Like!
Of course, you can always cut to the chase and bring the sun to your plant!
Grow lights are an excellent option because they allow you to place your String of Pearls wherever you want.
They can be quite attractive home features in their own right, as well as provide a good, consistent level of light tailored to plant growth.
They’re a surefire way to ensure that your light-loving String of Pearls gets enough light to thrive.
For your String of Pearls, choose a grow light that is broad-spectrum, with a timer. (Check out the latest price on Amazon here)
“Broad-spectrum” is closest to the bright direct sunlight all succulents enjoy, and a timer allows you to control how much light your plant receives, and when.
Signs That Your String of Pearls Is Getting Too Much Light
Of course, there can be too much of a good thing! Even a light-loving plant can become overly exposed, and while the light is one thing, heat is quite another.
Keep an eye out for the following issues, particularly in recently relocated plants. You may need to reduce the intensity for a week or so to give them time to adjust.
Scorched String of Pearls
Darkened patches that crisp or crack indicate that your String of Pearls is overheating in bright light. Your plant has been sunburned.
It’s also possible that your plant has come into contact with hot glass and is being fried.
String of Pearls Shriveling
If your brightly lit String of Pearls is shriveling, it is indicating that it has been overheated and overworked! Each pearl is a tiny reservoir of water.
A shriveled String of Pearls has either used that water to cool itself or has run out due to excessive photosynthesis. It’s time to take a break!
Not only will it need to be relocated to a cooler, more shady location, but it will also require thorough watering.
String of Pearls Pale
When stressed, your String of Pearls will try to conserve its resources. A pale Pearl is one that is overwhelmed.
Just like a String of Pearls that are suffering in the shade, this plant needs a new home.
Brown Spots or Pale and Translucent Spots Developing on the Leaves
Young brown or pale leaves with irregular clear patches are the results of a plant doing its best under adverse conditions.
Your String of Pearls is still growing and producing new leaves, but not enough for those leaves to be healthy.
Yellowing and Thickening of New Growth
Another defensive strategy, thickened growth indicates that your String of Pearls is doing everything it can to protect itself from excessive heat and light.
Thick growth is far more resistant to high temperatures and scorching sun than lighter growth, but while your plant will survive with these defenses in place, it will not thrive.
String of Pearls Turning Purple
Purple pearls might be valuable to jewelers, but to your succulent, it’s another response to stress.
This purple color is caused by anthocyanins, a purple pigment that acts as a sunscreen, deflecting light and protecting the leaves of your String of Pearls.
Some folks find a purple String of Pearls quite attractive, and deliberately stress theirs to vary the color of the pearls.
But if yours just up and turns purple for no clear reason, it may be worth checking the light levels before damage can be done. I’ve written more on purple Pearls here.
What to Do if My String of Pearls is Getting Too Much Light?
Again, this is a problem that is easy to solve. Relocate your plant to a less exposed position.
I’d also suggest you give your poor Pearls a thorough watering, and if you’re in the growing season a dose of very diluted succulent fertilizer (Check out the latest price on Amazon here) to help your plant repair any damage.
Your String of Pearls is designed to withstand the rigors of desert life, with its ever-changing and extreme conditions.
Once you’ve adjusted your plant’s lighting, it won’t be long before it’s producing perky strings of fat green pearls for you to enjoy.