String of Pearls : Basic Care and Treatment

String of pearls is a succulent plant with an odd yet attractive appearance. As a houseplant, it has decorated many houses with their pea-like leaf and thin stem. Despite its size and origin, it is one of the best winter houseplants candidate out there.

Origin and features

In their hometown, South Africa, string of pearls (Senecio rowleyanus, now Curio rowleyanus) plants mostly live in the ground. In the arid, desert region of Africa, these plants stunningly survive with their unique features. It is a perfect plant from beginners, as some neglect will not kill the plant right away.

Foliage

Green spherical leaves and skinny trailing stems resemble beaded necklace. Beside string of pearls, this plant has another nickname such as string of peas. The fleshy round foliage is able to store water, thus it doesn’t need excessive watering. Additionally, this feature is crucial when it comes to an extreme condition i.e. less water and high temperature.

Flowering

Sometimes, people would welcome the small and unattractive flower string of pearls. Even though it is rare to see the flowers bloom indoor, you can attempt to promote their growth with certain condition.

• In winter, reduce the watering frequency but never let the soil to be completely dry. Then, keep a constant temperature of 13-16°C. Next, put the plant on the windowsill and don’t put it close to heat register.
• If you are lucky, the flowers would bloom in spring. You will see tiny (1/2-inch) white flowers that look like daisy (trumpet-shaped). They have yellow anthers, red stamens, and cinnamon-like scent. These flowers would last around 1 month.

Growth

In terms of look, with a proper care this plant would grow beautifully from 60 centimeters to 1 meter long. The stems could grow pretty fast around 5-15 inches every year. To create a “slimmer” looks, put the stem tips back in the soil to form a small loop.

Due to its natural desert habitat, there is no specific time to plant string of pearls. However, it would thrive best in warmer season. It can last for five years under ideal condition. Instead of repotting the mature plant, propagation will ensure its age longer.

Toxicity

String of pearls contains a mildly toxic sap. In accidental consumption or ingestion, you might experience the following symptoms:

• dermatitis/severe skin irritation,
• diarrhea
• drooling,
• inflammation,
• itching,
• nausea
• pain,
• rash,
• vomiting,

Pets could also suffer from it by showing signs such as painful skin, lethargy, itching, and drooling which lead to pet’s distress.

The fragile leaves could easily fall from their stems. Consequently, pets and children who like to move around might find it an interesting object. So, secure the plant out of the reach of kids and pets. For further prevention, wear gloves when handling this plant.

Light

String of pearls plants could accept direct sunlight as it could flourish them. Nonetheless, they still have demand regarding lighting condition.

Lighting distribution:

• Soft direct sun (NOT midday sun) for few hours. Because of the round leaves, it is harder for string of pearls to carry out photosynthesis. That is why it needs same direct sunlight. Moreover, both the top and side of the plant should receive the sunlight equally.
• Indirect light for the rest of the day would be fine. You might need to adjust the plant position throughout the day. For example at noon when the sun shines very bright, consider using partial shade. Or you can move the plant further from the window.
• Consider indoor lighting. If you don’t have a spot with enough light, try to install fluorescent light fixtures. Place them 6 to 12 inches above the plant and let them shine around 12- 16 hours/day to support the optimum growth.

Note. In total, this plant needs 6-8 hours of bright and indirect sunlight.

Lighting issue

Too much light causes yellow and brown leaves. On the other hand, the plant could be “bald” if it lacks of light, especially when the light does NOT come from the top. Insufficient light may also lower the plant defence against pest and disease.

Location

As a versatile plant, string of pearls plants could grow both indoor and outdoor. They basically need a dry and warm environment with bright indirect light all year around.

Indoor placement

• Keep a suitable distance from window. Some suggest to place the plant near east, south, or west-facing window. Whatever you choose, they key is to observe how much light comes from each window.
• In several regions, there is a higher chance of sunburn. For this reason, keep a distance of 5-10-inches or 15 cm away from your preferred window. Additionally, a closed window is better to prevent direct sunlight and cold air outside.
• Grow in a hanging plant holder. A long, thin hanging stems makes a plant holder (or hanging basket for some) a perfect item to grow this plant. Another option is to use a dish because of the plant’s terrestrial nature. Simply intertwine the branches and you will create a similar display like in the wild.
• Don’t put the plant near low temperature and high humidity sources. An expert says that conservatory, bathroom, and kitchen are not the best spot for string of pearls. These places might hit the plant with sudden temperature and humidity change. And this plant hates that.

Outdoor requirement

• Zone 9 or warmer areas are ideal to grow string of pearls outdoor. Since it would be dry and hot, you might have to water more often.
• For easy access, grow the plant in container. This is particularly handful when you live outside the zone mentioned above. When the temperature gets lower than 30° Fahrenheit (-1°C), it is more convenient to bring it inside while still inside the container.
• Any protected or shady area is okay. The examples here include patio and yard. Remember that although this string of pearls plants need bright light, direct sun exposure at noon would hurt them.

Temperature and Humidity

• In active growing season, the average indoor temperature should be in the range of 22° C. You can achieve it easily as the plant could adjust in most average indoor temperature.

During cold months, maintain indoor temperature at 10-13°C. Nevertheless, the plant is vulnerable to frost. Thus, protect the plant by NOT leaving it outdoor in winter when temperature drops below 10°C. If not, dropping leaves will occur and ruin your plant looks.

• A standard humidity level in most household (40%) is enough for string of pearls. It usually ranges from average to dry humidity level. High humidity is not the plant style. So, don’t place them in a humid areas at home such as bathroom and kitchen.

Frequent misting to raise humidity is unnecessary because the plant prefers low humidity like in its original habitat. If you keep misting the crown part of plant, it might lead to rot and pathogen development.

Read also : String of Turtles : Planting, Propagating, and Potential Issues

Soil

Soil requirement

Options

Any succulents require well-drained soil including string of pearls. Actually, regular succulent potting soil is the standard, but sandy soil is more preferable. Moreover, the soil pH must be neutral to acidic. Here are other potting mix you can choose:

• cactus potting mix
• soil-based compost and sharp sand (3:1)
• basic potting soil + perlite + coarse river sand/pumice

Note. Regular potting soil is NOT the best recommendation since it retains more water. As a result, the soil is getting wet longer than it should be.

Level

When planting this plant, make sure the crown parts are on the same level of the pot upper edge. At least, the level should be 0.5 to 1 inch lower. In this way, it will improve aeration and protect the plant from experiencing wet soil.

Potting

Material

Both terracotta and unglazed ceramic pots are the popular choice of many gardeners. These types of pot support quick draining, preventing overwatering and rot. Beside material quality, also check the drainage holes of the pot. This is important since this plant is not a fan of waterlog and wetness.

Then, what if you already buy one without drainage hole? No worry, there is a trick for that. You can add a layer of perlite, gravel, or pebbles on the pot bottom (inside).

When choosing this addition, please consider the weight. If your hanging pot is unable to hold the heavy pebbles for instance, choose a lighter material. These excellent matters prevent the root from sitting too long in soggy soil. Yet, you should NOT overwater only because you have a back-up plan.

Size

A good size pot is important to let the plants expand their growth. An oversized pot is prone to overwatering.

The shallow roots of string of pearls require a shallow pot too. If you plant them too deep, it will result in poor aeration. Eventually, the water stays longer in the soil. Once it occurs, the thin stems will rot faster.

Tips.

• When drain holes get blocked, open them using pointed object. For example: chopstick, knitting, needle toothpick, and so on.
• If the soil has a hard time to dry, consider replacing it with cactus or succulent mix.

Water

The wild nature of South Africa has forced these plants to survive from drought in particular. As their leaves are able to store water, watering them once a week is a common practice. In cold season, it would be enough to water the plant once or twice a month.

The right time for watering is:

• after the soil is completely dry down to the pot base,
• when 1-1.2 cm (minimum) of soil dry, or
• if the foliage begins to shrivel or flatten.

Tips

• A simple check by using finger will tell you how thirsty the plant is. Once you feel the soil is not damp and has a sandy texture, start watering the plant.
• Many suggest to water the plant from below. This method allows the plant to soak the necessary amount of water each time without hurting the foliage. Reversely, watering from the top or leaves has risk of leaf spot issue. Furthermore, ensure that the excess water flows out through drainage holes.
• Other variables such as soil, pot, and temperature affect the watering frequency. In outdoor summer setting, you may increase the frequency based on the plant condition. It is also not a bad idea to let the rain takes over your watering job sometimes.

Watering issue

Too dry condition

The leaves indeed play a crucial role in watering. However, it is a different case with the slim stems. These stem cannot hold much water like the foliage and they will be dry faster without enough water.

Overwatering

In a soggy soil, the roots become unable to get the oxygen. Consequently, you will get brown and mushy leaves.

Fertilization

In general, succulent plants don’t need fertilizer. Still you can feed them by following the right instruction. Worm compost, compost, and liquid kelp or fish emulsion are quite effective to promote plant health and strength. These are organic based, so it is safe for your plant.

Frequency

During spring and summer, feed the plant biweekly or once every 4 weeks. Even though there is no need to feed the plant in fall and winter, other suggest to give fertilizer every 6 weeks.

Dosage

Over fertilizing is a bad news for this plant. Aside from the frequency, the dosage is essential too. Apply a water-soluble or balanced liquid fertilizer and dilute at half strength. Instead of the strong one, always go with a weak and little fertilizer.

Gritty gravel containing phosphorus is the common choice for feeding string of pearls. It would keep the plant stronger to avoid disease and pest.

Pruning

To maintain the plant size and appearance, very occasional pruning is necessary. First, prepare clean shears or scissors. Then, cut the dead leaf and stem, as well as leggy stems which also lost the leaves. For a too long and healthy part, try to propagate instead of cutting and throwing it.

Read also : String of Hearts : Caring for a Semi-Succulent Plant

Repotting

Signs to repot include root bound, slow growth, and losing leaves. Due to the limited space, the roots will grow in circular motion and spread outside the pot. Repotting is a good time to prolong the plant life. ONLY repot the plant in spring when necessary.

Steps

1. Gather the trailing stems on the pot center.
2. To protect the pearls, remove the hook of the hanging basket/pot before putting them down.
3. Flip the pot in one side while covering the top pot lightly.
4. Squeeze/tap the pot bottom gently or cut the pot into 2. These actions aim to loosen the soil and decrease the plant damage especially on the leaves.
5. Prepare a slightly larger pot (2-3 inches deep and wide) or 10% bigger container. Unlike the general assumption, actually it is better to grow the plant in a spreading position instead of trailing. It is because in the wild, this setting allows the plant to grow fuller and longer.
6. Fill the new pot (i.e. ceramic or terracotta pot plus drainage hole) with succulent or cactus potting mix. To improve drainage and aeration, you can add coarse sand or perlite.
7. Create a space in the middle for the plant.
8. Put the plant inside and fill the rest of pot with soil and leave 1 inch space before reaching the pot edge.
9. Water the plant thoroughly and return it back in a bright indirect location.

Note. Because of the delicate leaves, treat this plant carefully. If some leaves fall during the process, put them back in the soil. Then, we hope that they would grow as new plants.

Propagation

Early spring to late summer is the best timing for propagation, although some do that in early fall too.

Stem cutting method

The simplest way to propagate string of pearls is through stem cuttings. It is easy and quick even for beginners. After 3-4 weeks the roots will start to establish.

1. Cut some stems with ±10 cm length (4 or 5 inches) right under the foliage node.
2. Remove the two leaves at the bottom end and lay it down for 1 or 2 days to let them dry and heal.
3. Fill the pots with cactus or succulent soil. Other people use cactus compost/compost and sharp sand. Make it a bit damp and dig a hole in the center for planting the stems.
4. Put each stem cutting in the soil around 1 inch deep. All leaves must stay on the soil surface.
5. If you forget to cut the 2 lower leaves, curl the tendril. Push it lightly till it touches the soil.
6. Place each pot in the bright indirect spot inside the house or shaded area outdoor.
7. For a few days, mist the stems moderately to prevent dryness.
8. Then, you can water the plants thoroughly when the soil dries up.

Seed method

On the other hand, seed propagation is possible but more challenging. First, the flowers must finish pollination in order to produce seeds. Since the flowers rarely bloom, it is unpredictable when the seed would be available.

Even if it is likely to fail, here are the steps of seed propagation.

1. Once you obtain the seeds, insert them in cactus/succulent potting mix.
2. Never let the soil dries. You can provide enough water or misting them.
3. If you don’t have much time, cover the pot with plastic bag to encourage germination.
4. Germination rate would be faster during spring or summer. However, you can expect several weeks up to 2-3 months to see the result.

Pests

Even as a low maintenance plant, string of pearls could become the pest target.

Common pest

• Aphids. This pests are craving for the plant juice. Once they suck the sap, wilted and discolored leaves would occur. Eventually, your plant might die.
• Mealybugs. They produce white wax-like substance on the plant. Not only suck the sap, this pests also attract ants to come.

What to do

In addition to both pests above, gnats mites, and whiteflies might weaken the plant’s immune.

• First, conduct regular inspection. Since the pests are tiny, check the plant carefully. Finding them earlier will minimize the damage.
• Second, apply neem oil or insecticidal soap. Dilute this organic products with water before use. In case they fail, you may go with synthetic pesticides.
• Third, bring natural enemy. Ladybug and lacewing are two predatory insects you can use to fight the pests.

Note. Sometimes, the pests come from nearby plants which are weaker. Hence, you might have to deal with other plants too to prevent further spread and eliminate the pest completely.

Potential Diseases

Water matters, including under watering and overwatering are the main source of many string of pearls diseases.

• Dropping leaf –> Cause: the plant is too cold
• Missing leaves on top/balding –> Cause: lack of light
• Root rot –> Cause: overwatering
• Shriveling leaf–> Cause: overwatering or under watering, too dry condition
• Yellow/gray leaf–> Cause: pest infestation

Handling the worst situation

We would like to go deeper with root rot as it threatens the plant life.

Symptoms: brown/black, mushy stem, purple/brown/yellow leaves, without quick treatment fungus might grow and the plant will die.

Solution:

• Let the plant to get dry first.
• If it still not recover, remove the infected leaves, stems, and roots at once.
• Replant the remaining healthy parts in new soil.
• Use new small pot or sterilize the old pot.

Buying String of Pearls

• Prepare a good spot and pot for the plant at home.
• In local garden stores and nursery, there is a possibility that the plants stay in a wet condition. Therefore, you must check it before you buy it since overwatering is not easy to solve.
• If you buy online, take out the plant carefully from the box. Due to unknown variable during its delivery, be prepare on how the plant condition would be.

Between String of Pearls and String of Tears

These plants come from the same family and have similar feature.

• The leaves of string of pearls are more like pea shape. It is able to grow around 90 cm long.
• In contrast, string of tears has raindrop-shaped foliage. The vine length could stretch up to 30 cm.