Bertolonia, or Jewel Plant, is a genus of mainly evergreen plants. All species of this genus are small, even dwarfed, with a creeping growth habit. They’re tender perennials, known for the exotic coloring of their leaves. These plants are native to the tropical forests of Brazil, although a few have been found in Venezuela.
These are somewhat rare plants, but well worth looking for if you have a terrarium or plant case to fill. They’re not a good choice for the living room or office, however. Bertolonia needs the high humidity of its jungle home as well as warm temperatures.
Bertolonia requires constant warmth and a humid atmosphere and will not thrive without them.
Species of Bertolonia
The Bertolonia genus consists of about 35 accepted species, with more being discovered all the time. These pretty little creeping plants are native to the jungles of South America. Most are native to Brazil, but several species have been found in Venezuela. They feature colorful leaves, many with interesting textures or shiny, even metallic finishes.
Bertolonia maculata
Often best known as “jewel plant,” this Brazilian native plant is a tropical evergreen perennial. B. maculata has oval leaves with pale green veins. The leaves are olive green with silvery stripes down the center.
The plant grows to about 6 inches high and the leaves measure about 3 inches long. It flowers several times a year with tiny pink blooms.
Bertolonia marmorata
The most popular species of this genus has heart-shaped leaves that are mossy green and furry. The stems crawl over the surface of the potting mixture, turning their tips upwards. However, they never get larger than 6 inches tall.
- marmorata leaves feature prominent white stripes. (The variety sanderianahas leaves heavily splashed with silver.)
The flowers are less than one inch in diameter, purple, and star-shaped, with five petals each. The flowers open singly on stiff flower stalks of about 3 to 4 inches long.
Bertolonia mosenii
This species of Bertolonia is similar to the others in size. However, the leaves are bright emerald green and rounded with striations from the stem to the tips. This species features white star-shaped flowers which, in the wild, appear right before the rainy season.
This species is the most common of the Bertolonia in the Brazilian Atlantic forest. Scientists recently discovered that they require rain to reproduce, as heavy drops of rain help disperse seeds from the mature fruits.
Bertolonia carmoi Baumgratz
This species features shiny, deep-green, ruffled-looking leaves, with less “fur” than other varieties. The leaf undersides are a light purple in color
Bertolonia hirsutissima
This recently discovered species features bright green bumpy leaves and light pink flowers. The specific name, “hirsutissima,” refers to their hairy stems
Bertolonia lucernula
This very rare species of Bertolonia is newly discovered. Its leaves are dark green, nearly brown, and it blooms with bright pink flowers. Because only three specimens have been found, it is already considered critically endangered.
Bertolonia nymphaeifolia
This species offers fuzzy green leaves with a purplish hue. Immature leaves are light green with a lilac hue. It blooms with white flowers that have pink-tipped petals.
Bertolonia Description
This low-growing, herbaceous perennial is a member of the Melastomataceae family and features leaves that vary in shape, color, and texture depending on the exact species.
The two varieties most widely available include B. marmorata and B. marmorata. Other species are commercially available, but they’re relatively rare and can prove expensive.
Culture
This tropical rainforest plant is found on moist jungle floors near the equator. It is only hardy to USDA zone 11 and completely intolerant to frost. It requires temperatures above 60 degrees Fahrenheit and high humidity.
Noteworthy Characteristics
The most striking quality of Bertolonia is its colorful leaf patterns. Depending on the species, these leaves may be rounded and puckered. Other varieties will feature oval leaves with silvery metallic stripes down the center of each leaf. Some species feature heart-shaped leaves of deep green.
Indoors, Bertolonia blooms several times a year. In the wild, however, they bloom yearly, depending on rainfall.
Problems
Cultivation of Bertolonia is difficult. It grows slowly and does poorly in less than the most perfect environment. It’s not a beginner level houseplant.
Despite its love of humidity, it can contract powdery mildew or gray rot if leaves are left constantly wet.
Uses
Bertolonia is best grown in a greenhouse or terrarium, with well-controlled warmth and humidity.
Bertolonia in terrarium
Houseplant Care Instructions for Bertolonia
If you like a challenge, you may want to try growing the jewel plant. To add Bertolonia to your houseplant collection successfully, you’ll need to know how to care for it like an expert.
Temperature
During spring and summer, keep temperatures warm. Anywhere between 72 and 77 degrees Fahrenheit is ideal.
In fall and winter, lower temperatures down to 65 degrees is acceptable.
Light
Bertolonia evolved to grow in low light conditions under forest canopies. While your plant will not thrive in complete shade, avoid placing it in direct light. Opt for filtered or dappled light from a nearby window.
Watering
Keep the soil moist at all times during the growing season. Check it frequently to ensure the potting medium is moist.
During its dormant phase in winter, allow the top of the soil to dry out a little between watering. Provide only enough water to keep it from drying out completely.
It’s important to avoid getting the leaves wet to avoid gray rot and powdery mildew. We recommend bottom watering for this plant. Use a deep pot saucer and keep it topped up with distilled water to ensure it stays moist without wetting the leaves.
Feeding
Fertilize your Bertolonia every month during the growing season with a dilute houseplant food.
Air humidity
Moist air is vital to your Bertolonia’s long life and health. Strive to maintain a relative humidity reading of 70 to 80 percent. Stand the pot on a pebble tray or provide a humidifier. You can mist the leaves occasionally, as long as the plant has good ventilation.
Another option is to grow them in a large terrarium where they’ll receive the warmth and humidity they require. A terrarium will keep the environment humid with less effort.
If you’re not ready to purchase one, make your own from found materials around your home. Watch the video below for some DIY tips and tricks:
https://youtu.be/9B7aIULFjrc
Potting and repotting
Bertolonia grows slowly, so you should not have to repot it frequently. Once the plant stems are hanging over the pot and no longer touch the soil, it’s time to provide it with a bigger home.
If necessary, repot your Bertolonia in the spring. Use a potting mixture composed of equal parts of peat moss or coconut coir, leaf mold and coarse sand or perlite. A commercially mixed peat-free African Violet mix should stand in nicely.
Propagation
Take stem cuttings in spring if you want to try to propagate your Bertolonia from cuttings. Fill a small pot with well-moistened potting mixture, coconut coir, or vermiculite. Poke one hole for each of your cuttings around the rim of the pot.
Take your cutting below a leaf node and remove all but the top two to four leaves. Dip the cut end into rooting hormone and gently place the cutting into one of the prepared holes in the pot.
Set your pot in a propagation dome if you have one. Alternatively, enclose the entire pot into a plastic bag. A plastic grocery bag will do in a pinch.
Place your cover pot pots in plastic bags and stand them in medium-level light in a warm environment. Keep your cuttings at a temperature of at least 77 degrees.
Remove the plastic bag after two weeks to check your cuttings for rot and to provide some healthy ventilation. Ensure the soil is still damp and cover it again. Then, check your cuttings weekly, removing any failed or squishy cuttings. Rooting should occur in about six to eight weeks.
Common Pests and Plant Disease
Bertolonia is subject to any common houseplant pest, such as spider mites or mealy worms. Use neem oil or a mild insecticidal soap spray to control these pests.
The plant is also subject to gray rot and powdery mildew. Avoid saturating the leaves and ensure the plant has good ventilation to prevent these problems.
You can also treat powdery mildew with a mixture of 1 Tablespoon common 3 percent hydrogen peroxide to 20 ounces of distilled water. Spray the plant daily for three days in a row, ensuring it has good airflow around it. Then, follow up by spraying weekly until the disease is under control and no longer imminent.
Conclusion
Bertolonia is called the “jewel plant” for a good reason. These precious horticultural gems are real rainforest treasures. Their attractive leaves and sweet, tiny flowers add their diminutive charm to any collector’s inventory. They’re not the easiest houseplant to grow. However, if you can give them their own slice of jungle floor with a warm terrarium, you won’t regret it.
Editor’s Note: This post was originally published in October 2016 and has been completely updated.