Ever see a houseplant and think someone painted a watermelon rind on every leaf? That’s the watermelon peperomia, a small, tidy plant with silver-and-green striped leaves on bright red stems.
NC State Extension describes it as a tropical evergreen with an erect, bushy habit, native to Brazil, that grows up to 8 inches tall.
Its leaves are smooth, waxy and striped like a watermelon, and they attach to their red leaf stalks in the middle of the leaf (a rare “true peltate” attachment) rather than at the edge.
It’s a member of the pepper family, Piperaceae. NC State’s peperomia genus page says the name Peperomia comes from the Greek peperi (pepper) and homoios (resembling), a nod to its relative, the black pepper plant, Piper nigrum.
The watermelon peperomia itself doesn’t look much like black pepper; it’s the family tie that the name points to.
Watermelon Peperomia Quick Care Tips
- Botanical name: Peperomia argyreia (the name on most plant tags and the ASPCA list); NC State and Clemson spell it Peperomia argyraea
- Older name: Peperomia sandersii
- Common names: Watermelon peperomia, watermelon begonia (it is not a begonia), watermelon plant
- Pronunciation: peh-per-ROH-mee-ah ar-jy-RAY-ah (NC State)
- Family and origin: Piperaceae (pepper family); native to Brazil
- Growability: Easy, low maintenance
- Hardiness zones: USDA 10a to 12b (NC State)
- Size: Up to about 8 inches tall (NC State, Clemson)
- Growth rate: Slow (NC State)
- Flowering: Thin, cream-colored flower spikes 2 to 4 inches long in spring and summer; not showy
- Light: Bright, indirect light; no direct sun
- Temperature: Warm rooms; protect from cold drafts (NC State); outdoors only once nights stay at 60°F or higher (Clemson)
- Humidity: Average home humidity is fine; a humidifier helps in winter (Clemson)
- Soil: Well-drained houseplant or cactus potting mix (Clemson)
- Water: Let the soil dry out between waterings; water less in winter
- Fertilizer: Low-strength liquid fertilizer occasionally in spring and summer, or slow-release granules once a year (Clemson)
- Pests and problems: Mealybugs, scale, spider mites, whiteflies, aphids and fungus gnats; root rot from overwatering; leaf spot
- Propagation: Leaf cuttings with a piece of leaf stem, stem cuttings or division
- Pet safety: Non-toxic to dogs and cats (ASPCA)
Watermelon Peperomia Care Instructions
What’s in a Name?
You’ll find this plant sold as Peperomia argyreia, and that’s the name the ASPCA uses too. NC State Extension and Clemson Extension now spell it Peperomia argyraea, and NC State lists Peperomia argyreia and Peperomia sandersii as previous names.
Same plant, slightly different spelling. NC State and the ASPCA both list “watermelon begonia” as a common name, but it’s a peperomia, not a begonia.
Size and Growth
Watermelon peperomia stays small. NC State says it grows up to 8 inches tall, and Clemson calls it a small, bushy plant that reaches about 8 inches, which makes it ideal for an office or a small space.
Don’t expect it to race. NC State rates its growth rate as slow. A University of Florida IFAS foliage research note (UF/IFAS Peperomia Production Guide) describes it as a rosette type, with dark green leaves, silvery-gray zones radiating from the leaf center, slightly cupped leaf blades, and long reddish leaf stalks.
Flowering
The flowers are a bonus, not the show. NC State describes erect spikes 2 to 4 inches long, covered in minute, white-to-cream-colored flowers.
Clemson says peperomia flower spikes appear while the plant is actively growing in spring and summer, are considered unattractive, and resemble a rat’s tail.
Don’t be surprised if yours never blooms, though: NC State’s genus page says that, as houseplants, peperomias typically will not flower.
Plenty of growers snip them off. Clemson says removing the flower spikes lets the plant focus its energy on making leaves. If you like them, leave them, and cut them off once they fade.
Light
Bright, indirect light suits watermelon peperomia best. NC State says the plant prefers bright indirect sunlight. Clemson suggests placing peperomias where they get indirect light from an east- or south-facing window, and says they can even tolerate somewhat low light near a large north-facing window.
Keep it out of hot, direct sun. Clemson warns that direct sun can scorch a peperomia’s leaves.
Temperature
Treat it like the tropical plant it is. NC State’s genus page says peperomia’s other common name, radiator plant, refers to its preference for warm conditions, and both NC State pages say to protect the plant from cold drafts. Keep it away from drafty doors, cold windows in winter and air-conditioning vents.
Outdoors, it’s a plant for frost-free gardens only: NC State lists USDA zones 10a to 12b.
Everywhere else, Clemson says you can move peperomias outdoors for the summer once night temperatures are consistently 60°F or higher, starting them in deep shade and keeping them in a bright but shady spot out of direct sun.
Watermelon Peperomia Watering
Avoid overwatering with this plant. Clemson Extension puts it plainly: “Peperomia prefers to dry out between waterings. If it is overwatered, it will drop its leaves.”
NC State’s watermelon peperomia page is more specific: let the topsoil dry to the touch before watering, and water less in the winter. It says the plant can’t handle either wet or very dry soil. Too much water causes root rot, and too little makes the plant wilt.
When you water, water until it drains, then let the pot finish draining before you set it back in its saucer, as Clemson recommends. Don’t leave it sitting in water.
UF/IFAS Extension fact sheet on the baby rubber plant (Peperomia obtusifolia) says it is best to err on the dry side when growing peperomia, and the University of Arkansas Cooperative Extension Service says peperomias have a small root system and are easy to overwater, especially in winter when growth is slow.
Humidity
Average indoor humidity is usually fine. NC State’s genus page says peperomias can thrive in most homes’ humidity levels, but if your home is very dry, consider a humidifier. Clemson says peperomia benefits from a humidifier in winter.
A pebble tray or humidifier raises humidity without wetting the leaves, and dry leaves matter: Clemson says keeping leaves dry when you water can prevent fungal leaf spots.
Fertilizer
Go easy on the food. Clemson says to fertilize peperomia only when it is actively growing in spring and summer, using a low-strength liquid fertilizer occasionally during the growing season, or a slow-release granular fertilizer once a year. Follow the label for the amount, and skip feeding through fall and winter.
There’s a good reason to under-feed rather than over-feed. The UF/IFAS research note says peperomia roots are very fine and easily damaged by too much salt in the root zone, and that the roots often die back before you see symptoms in the leaves.
Soil and Repotting
Drainage comes first. Clemson recommends a well-drained houseplant or cactus potting mix, and NC State’s genus page recommends a moist, well-drained loam-and-sand mix.
The UF/IFAS research note says peperomia roots are very sensitive to waterlogged soil, and that commercial growers use well-drained peat-lite mixes with coarse particles such as perlite to give the roots air.
Don’t rush to repot. NC State says watermelon peperomia won’t need repotting often because it thrives being pot-bound, and the University of Arkansas says peperomias are usually best grown in relatively small pots.
Clemson says the plant can stay in the same pot for several years, and when you do move it, use a pot only slightly larger than the grower’s pot. Whatever you choose, make sure it has a drainage hole.
Grooming and Maintenance
This is a low-fuss plant. Clemson says to trim off old leaves when needed, and to prune a stem just above a leaf node if you want the plant to branch and look fuller. Pinch off any yellow or damaged leaves to keep it tidy.
Propagating Watermelon Peperomia
Want more watermelon peperomias? The UF/IFAS research note says the plant is usually propagated from leaf cuttings, and NC State lists leaf cuttings and division.
UF/IFAS adds that terminal (tip) stem cuttings can be used with all peperomia types. Iowa State University Extension lists peperomia as a houseplant that roots well from leaf petiole cuttings (a leaf with its leaf stem attached).
Clemson’s leaf-cutting steps are simple:
- Remove a leaf with at least an inch of the petiole (leaf stem).
- Insert the leaf stem into a rooting medium.
- New plants form at the base of the petiole.
- Once they do, separate them and pot them up.
Iowa State adds a few details: leave 1 to 1½ inches of leaf stem, treat the end with rooting hormone if you like, and set the cutting in at a 45-degree angle. Keep it in bright, indirect light with high humidity (a loose plastic bag or dome helps).
For rooting cuttings, Iowa State says an air temperature between 65°F and 75°F is ideal. Roots usually form in three to four weeks, and small plantlets appear at the base of each leaf stem in six to eight weeks.
Can you root it in water? Many houseplants will. But Iowa State says roots that form in water are coarser and not well adapted to potting soil, so water-rooted cuttings may wilt, drop leaves or brown once potted. Rooting medium is the better bet.
Related: How To Propagate Peperomia Baby Rubber Plants
Watermelon Peperomia Pests and Plant Diseases
Good news: NC State says watermelon peperomia has no serious pest or disease problems. It can still pick up the usual houseplant pests.
NC State lists mealybugs, scale and aphids for this plant, and Clemson adds spider mites, fungus gnats and whiteflies for peperomias in general. Check the undersides of leaves and the leaf stalks periodically.
For mealybug infestations, the University of California Statewide IPM Program (UC IPM) says that on small infestations on houseplants, a 70% (or less) solution of isopropyl (rubbing) alcohol in water can be dabbed on the mealybugs with a cotton swab, after testing it on a small part of the plant 1 to 2 days beforehand to check for leaf burn.
It says insecticidal soaps, horticultural oils and neem oil applied directly to young mealybugs can reduce their numbers.
Not every source agrees on alcohol: UF/IFAS Gardening Solutions says alcohol is phytotoxic (it causes leaf burn and other plant injuries) and warns that dish “soaps” are detergents, not true soaps. If you spray, use a product labelled for the job and follow the label.
Water causes more trouble than bugs. Clemson says root rot, caused by overwatering, is the most common disease of peperomia, and NC State says this plant can develop root rot quickly from overwatering. Leaf spots are another thing to watch for.
The UF/IFAS research note says Phyllosticta leaf spot causes dark brown to black, ringed, dry spots on watermelon peperomia, commonly found on the leaf margins and spreading across the leaf; it advises removing infected leaves and keeping the foliage dry.
Related: Peperomia (Radiator plants) Diseases and Pests
Is Watermelon Peperomia Safe for Pets?
Yes. The ASPCA lists watermelon peperomia (Peperomia argyreia) as non-toxic to dogs and cats, and NC State Extension says this houseplant is not toxic to cats or dogs.
Clemson says most peperomias are considered safe for pets. Non-toxic doesn’t mean edible, though, so keep it out of reach of pets and small children.
Suggested Uses For Watermelon Peperomias
Watermelon peperomia is a natural desk or tabletop plant. NC State says it’s used as a specimen or desktop plant and looks best grouped with plants with similar care needs, and Clemson says its compact size makes it ideal for an office or small space.
In frost-free gardens (USDA zones 10a to 12b, per NC State), it can grow outdoors as a small groundcover in shade. Everywhere else, enjoy it indoors, or bring it outside in summer to a bright, shady spot once nights stay at 60°F or higher.
Where does your watermelon peperomia live, on a desk, a shelf or a windowsill? Tell us below!
Frequently Asked Questions
Is watermelon peperomia easy to care for?
Yes. NC State Extension rates it easy to grow and low maintenance, with no serious pest or disease problems. The main thing is water: Clemson Extension says peperomia prefers to dry out between waterings and drops leaves when overwatered. Give it bright, indirect light, a well-drained houseplant or cactus mix and a pot with a drainage hole, and let the pot drain after watering.
How often should I water a watermelon peperomia?
Water when the top of the soil is dry to the touch, as NC State Extension advises, and water less in winter. Clemson Extension says peperomia prefers to dry out between waterings and that overwatering causes leaf drop and root rot, its most common disease. Let the pot drain fully before setting it back in its saucer.
How much light does watermelon peperomia need?
Bright, indirect light is best. NC State Extension says it prefers bright indirect sunlight, and Clemson Extension suggests an east- or south-facing window. Clemson says peperomias can tolerate somewhat low light near a large north-facing window, but warns that direct sun may scorch the leaves.
How do you propagate watermelon peperomia?
Use leaf cuttings. UF/IFAS says watermelon peperomia is usually propagated from leaf cuttings. Clemson Extension says to remove a leaf with at least an inch of stem and insert the stem into a rooting medium; new plants form at the base. Iowa State University Extension says roots usually form in three to four weeks, with small plantlets in six to eight weeks.
Is watermelon peperomia toxic to cats and dogs?
No. The ASPCA lists watermelon peperomia (Peperomia argyreia) as non-toxic to dogs and cats, and NC State Extension also says it is not toxic to cats or dogs. Clemson Extension says most peperomias are considered safe for pets. Non-toxic doesn’t mean edible, so it’s still wise to keep the plant out of reach of pets and small children.