Rose Moss
Portulaca grandiflora · Moss-rose PurslaneUSDA | Grow Zone
10-11Outdoors all year in zones 10 to 11. Anywhere colder, keep it as a houseplant. Protect it below 50°F.
- Light
- Full sun, 6+ hours
- Water
- Deeply but infrequently
- Humidity
- 40-60%
- Temperature
- 70-90°F (21-32°C)
- Difficulty
- Beginner
- Growth
- Fast
- Mature size
- 6-12 in tall, 12-24 in wide
Portulaca grandiflora, commonly known as Rose Moss, is a vibrant, drought-tolerant succulent native to South America. Its colorful blooms and ability to thrive in poor soils make it a popular choice for gardens and containers.
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Ideal temperature
70-90°F is where it grows fastest. Below 50°F cold damage starts.
Spacing and harvest
- Mature size
- 6-12 in tall, 12-24 in wide
- Plant apart
- 12-24 in
- Frost
- Half hardy: light frost only
Everything it needs
9 essentials at a glance
Watering
Water Portulaca grandiflora deeply but infrequently, allowing the soil to dry out between waterings.
During the growing season (spring and summer), water every 1-2 weeks, adjusting frequency based on rainfall and temperature. In fall and winter, reduce watering to once every 2-4 weeks. Signs of over-watering include yellowing leaves and root rot, while under-watering may cause wilting and shriveling.
Light
This plant thrives in full sun, requiring at least 6 hours of direct sunlight daily.
Ideal placements include south-facing gardens or patios. Portulaca grandiflora can tolerate partial shade but may produce fewer flowers and exhibit leggy growth in low light conditions.
Soil
Portulaca grandiflora prefers well-draining sandy or loamy soil with a pH range of 6.0 to 7.0.
It benefits from a potting mix designed for succulents or cacti, which provides excellent drainage to prevent root rot.
Humidity
This plant prefers low to moderate humidity levels, typically thriving in environments with humidity around 40-60%.
To increase humidity, mist the plant occasionally or place it on a pebble tray with water. Signs of humidity stress include leaf curling and browning edges.
Temperature
Portulaca grandiflora thrives in temperatures between 70-90°F (21-32°C) and is hardy in USDA zones 10-11.
It can tolerate brief periods of heat above 100°F (38°C) but may struggle in temperatures below 50°F (10°C). Protect from frost during winter months.
Fertilizing
Use a balanced, water-soluble fertilizer with an NPK ratio of 10-10-10, applying every 4-6 weeks during the growing season.
Reduce or eliminate fertilization in fall and winter. Signs of nutrient deficiency include stunted growth and pale leaves.
Pruning
Prune Portulaca grandiflora in early spring to remove any dead or damaged stems and to encourage bushier growth.
Use clean, sharp scissors or pruning shears for best results. Deadheading spent flowers can promote continuous blooming throughout the growing season.
Repotting
Repot Portulaca grandiflora every 1-2 years or when it becomes root-bound.
Choose a pot that is 1-2 inches larger in diameter than the current one. Signs it needs repotting include roots growing out of the drainage holes and stunted growth. Carefully remove the plant from its pot, loosen the roots, and place it in fresh soil.
Propagation
Propagation can be done through stem cuttings or seeds.
For stem cuttings, take a 3-4 inch cutting from a healthy stem, allow it to dry for a few hours, then plant it in well-draining soil. For seeds, sow them in spring after the last frost, covering lightly with soil. Keep the soil moist until germination occurs, which typically takes 7-14 days.
When it's unhappy
Yellow leaves
Why it happens
Over-watering or poor drainage.
How to fix it
Allow the soil to dry out completely and ensure proper drainage.
Leggy growth
Why it happens
Insufficient sunlight.
How to fix it
Move the plant to a location with more direct sunlight.
Root rot
Why it happens
Consistently wet soil.
How to fix it
Reduce watering frequency and improve soil drainage.
Browning leaf edges
Why it happens
Low humidity or underwatering.
How to fix it
Increase humidity levels or adjust watering schedule.
Pest infestations (aphids, spider mites)
Why it happens
Dry conditions and lack of airflow.
How to fix it
Treat with insecticidal soap or neem oil, and improve air circulation.
Care through the year
Spring
In spring, prune any dead stems and begin a regular watering schedule as the plant comes out of dormancy. Fertilize every 4-6 weeks to promote growth.
Summer
During summer, ensure the plant receives full sun and water every 1-2 weeks. Deadhead spent flowers to encourage continuous blooming.
Fall
In fall, gradually reduce watering as temperatures drop. Continue to deadhead flowers and prepare the plant for winter by cutting back any leggy growth.
Winter
In winter, reduce watering to once every 2-4 weeks and keep the plant in a warm location, protecting it from frost.
Toxicity & Safety
Portulaca grandiflora is considered non-toxic to pets and children. It is safe to handle and consume, although excessive ingestion may cause mild gastrointestinal upset.
Good to know
How often should I water my Portulaca grandiflora?
Water your Portulaca grandiflora every 1-2 weeks during the growing season, allowing the soil to dry out between waterings.
Why are my Rose Moss leaves turning yellow?
Yellow leaves may indicate over-watering or poor drainage. Ensure the soil is drying out between waterings and check for drainage issues.
What type of soil is best for Moss-rose Purslane?
Portulaca grandiflora prefers well-draining sandy or loamy soil with a pH range of 6.0 to 7.0 for optimal growth.
Can I grow Portulaca grandiflora indoors?
Yes, you can grow Rose Moss indoors as long as it receives at least 6 hours of direct sunlight daily, preferably near a south-facing window.
How do I propagate Portulaca grandiflora?
You can propagate this plant through stem cuttings or seeds. For cuttings, allow a few hours for the cut end to dry before planting in well-draining soil.
What pests should I watch for on my Rose Moss?
Common pests include aphids and spider mites. Regularly inspect your plant and treat any infestations promptly with insecticidal soap.
When is the best time to prune Portulaca grandiflora?
Prune your Rose Moss in early spring to remove dead or damaged stems and encourage bushier growth throughout the growing season.
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