Natal Plum vs Old Man's Beard Plant Comparison

Compare these two plants side by side — care needs, key differences, and which is right for your home.

Natal Plum

Natal Plum

Carissa macrocarpa

VS
Old Man's Beard

Old Man's Beard

Usnea spp.

Natal Plum

Natal Plum

Carissa macrocarpa

Carissa macrocarpa, or Natal Plum, is a dense, evergreen shrub or small tree known for its glossy, dark green leaves and fragrant, star-shaped white flowers. It produces edible, plum-like red fruits that are rich in vitamin C. While it can be grown in containers, it's primarily an outdoor plant, thriving in warm climates. People grow it for its ornamental value, edible fruit, and use as a security hedge due to its thorny branches. It's not ideally suited as an indoor plant due to high light requirements and potential size.

Apocynaceae South Africa
✨ Features: Edible fruit (when ripe), fragrant flowers, thorny branches provide a natural barrier.
📖 Read Complete Natal Plum Guide
Old Man's Beard

Old Man's Beard

Usnea spp.

Old Man's Beard is a lichen, not a plant. It's a symbiotic relationship between a fungus and an alga or cyanobacterium. It appears as stringy, hair-like strands hanging from trees and shrubs. Its color ranges from pale green to grayish-green. It thrives in humid environments with clean air. People collect it for its purported medicinal properties and decorative uses. It is primarily an outdoor organism and cannot be successfully grown indoors.

Parmeliaceae Worldwide, various species have different distributions
✨ Features: Indicator of air quality; sensitive to pollution.
📖 Read Complete Old Man's Beard Guide

Quick Plant Comparison

Feature Natal Plum Old Man's Beard
Light Full sun to partial shade. Requires at least 6 hours of direct sunlight daily to thrive and produce fruit. Bright, indirect light outdoors. Full sun can scorch it in dry conditions.
Watering Every 7-14 days, depending on environmental conditions and pot size. Dependent on environmental humidity; mist when dry
Humidity 40-60% 60-90%
Temperature 18-27°C 5-25°C
Care Level Expert Expert
Growth Rate Moderate Slow
Max Height Indoors: Rarely exceeds 1-2 meters. Outdoors: Up to 4 meters. Variable, up to several feet long depending on the species and environment.
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-draining soil mix, such as a combination of potting soil, perlite, and sand. Does not grow in soil. Attaches to tree bark or other surfaces.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 30 minutes weekly (including watering, pruning, and pest control) 5 minutes weekly (for misting if needed).

🔬 Botanical Information — Comparing These Plants

Natal Plum

Scientific Name Carissa macrocarpa
Family Apocynaceae
Native To South Africa
Also Known As Natal Plum, Large Num-Num
Leaves The leaves are glossy, dark green, and oval-shaped, measuring 2-5 cm in length. They are arranged oppositely on the stems and have a leathery texture.
Flowers Natal Plum produces fragrant, star-shaped white flowers in spring and summer. While it can flower indoors with sufficient light, fruit production is less common.

Old Man's Beard

Scientific Name Usnea spp.
Family Parmeliaceae
Native To Worldwide, various species have different distributions
Also Known As Old Man's Beard, Tree Moss, Beard Lichen
Leaves Does not have leaves. Consists of thread-like or strap-shaped structures that are pale green to grayish-green in color.
Flowers Does not flower.

📏 Size & Growth — Plant Comparison

Natal Plum

Height Indoors: Rarely exceeds 1-2 meters. Outdoors: Up to 4 meters.
Spread Indoors: 1-1.5 meters. Outdoors: Up to 3 meters.
Growth Rate Moderate
Growth Pattern Natal Plum grows as a dense, multi-stemmed shrub or small tree. It can be pruned into a hedge or allowed to grow naturally. Its growth is relatively upright but can spread with age.

Old Man's Beard

Height Variable, up to several feet long depending on the species and environment.
Spread Variable, depending on the host tree and environmental conditions.
Growth Rate Slow
Growth Pattern Hangs in long, stringy strands from tree branches and other surfaces.

🌱 Propagation — Comparing Plant Growth

Natal Plum

Methods: Stem cuttings, Seed

Difficulty: Moderate

Tips: Take semi-hardwood cuttings in spring or summer. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the soil moist and provide warmth and humidity.

Old Man's Beard

Methods: Fragmentation (pieces breaking off and attaching to new surfaces).

Difficulty: Moderate

Tips: Ensure high humidity and a suitable substrate (tree bark). Success is not guaranteed.

✨ Benefits & Features — Comparing Plant Value

Natal Plum

The Natal Plum is unique for its combination of fragrant flowers, edible fruit, and thorny branches. Its drought tolerance makes it a suitable choice for xeriscaping.

  • ✓ Provides edible fruit rich in Vitamin C
  • ✓ Offers fragrant flowers that attract pollinators
  • ✓ Acts as a natural security barrier due to its thorns
  • ✓ Adds an ornamental touch to gardens with its glossy foliage
  • ✓ Can be used in traditional medicine (with caution and expert knowledge)
  • ⚠️ Toxic to pets

Old Man's Beard

It is a lichen, not a plant, representing a symbiotic relationship between a fungus and an alga. Its presence indicates good air quality, making it a valuable environmental indicator.

  • ✓ Air quality indication
  • ✓ Aesthetic appeal in natural settings
  • ✓ Potential medicinal properties
  • ✓ Educational value
  • ✓ Supports biodiversity
  • 🐾 Pet Safe

📅 Maintenance Schedule — Plant Care Comparison

Natal Plum

Repotting Repot every 2-3 years, or when the plant becomes root-bound.
Pruning Prune regularly to maintain shape and size, and to remove dead or damaged branches. Prune after flowering to encourage new growth.
Fertilizing Balanced liquid fertilizer (10-10-10) diluted to half strength, every 2-3 months during the growing season (spring and summer).
Seasonal Care In winter, reduce watering and protect from frost if grown in containers. In summer, ensure adequate sunlight and water during hot periods.

Old Man's Beard

Repotting Not applicable.
Pruning Not applicable.
Fertilizing Not applicable; obtains nutrients from the air and rainwater.
Seasonal Care Maintain high humidity during dry seasons. Protect from extreme temperatures.

🌞 Light Requirements

Natal Plum

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily to thrive and produce fruit.

Low light tolerant: ❌ No

Old Man's Beard

Bright, indirect light outdoors. Full sun can scorch it in dry conditions.

Low light tolerant: ❌ No

💧 Watering Needs

Natal Plum

Water deeply when the top inch of soil is dry. Avoid overwatering, which can lead to root rot. Allow the soil to dry slightly between waterings. Signs of underwatering include wilting leaves; overwatering includes yellowing leaves and soggy soil.

Old Man's Beard

Requires high humidity and moisture. In dry climates, misting may be necessary, but it primarily obtains moisture from the air.

🌡️ Temperature & Humidity

Natal Plum

Temperature: 18-27°C

Humidity: 40-60%

Old Man's Beard

Temperature: 5-25°C

Humidity: 60-90%

🤔 Which Plant Is Right For You?

Natal Plum

Natal Plum

Carissa macrocarpa
Care: Expert Time: 30 minutes weekly (including watering, pruning, and pest control) Beginner: No

Experienced gardeners in warm climates who want an ornamental shrub with edible fruit, and who can ensure it is kept away from pets.

✅ Choose This Plant If...

  • You live in a warm climate with plenty of sunshine.
  • You want an ornamental shrub with fragrant flowers and edible fruit.
  • You need a natural barrier or security hedge.
  • You are an experienced gardener looking for a new challenge.
  • You are willing to provide the specific care this plant needs.

❌ Skip This Plant If...

  • You have pets or small children due to the plant's toxicity.
  • You live in a cold climate with limited sunlight.
  • You are a beginner gardener.
  • You don't have space for a large shrub.
  • You are looking for a low-maintenance indoor plant.
📍 Ideal Location: Outdoors in a sunny location. If attempting indoors, a south-facing window with supplemental lighting is necessary.
🎨 Style: Mediterranean, Coastal, Tropical
🏠 Apartment Friendly: No
⚠️ All parts of the plant except the ripe fruit are considered toxic. Contains cardiac glycosides. Symptoms in pets include vomiting, diarrhea, weakness, and potentially more severe cardiac issues. Toxic to dogs, cats, and horses.
Old Man's Beard

Old Man's Beard

Usnea spp.
Care: Expert Time: 5 minutes weekly (for misting if needed). Beginner: No

Outdoor environments with high humidity and clean air.

✅ Choose This Plant If...

  • You live in a naturally humid environment with clean air.
  • You want to study lichens and their role in the ecosystem.
  • You are interested in traditional medicine and the potential uses of Usnea.
  • You have a shaded outdoor area where you can provide high humidity.
  • You want a natural air quality indicator.

❌ Skip This Plant If...

  • You live in a dry climate.
  • You have poor air quality.
  • You want an easy-to-care-for houseplant.
📍 Ideal Location: Outdoor areas with high humidity and clean air, such as forests or shaded gardens.
🎨 Style: Naturalistic, Woodland, Cottagecore
🏠 Apartment Friendly: No
⚠️ Generally considered non-toxic to humans and animals, but ingestion of large quantities may cause digestive upset.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Old Man's Beard ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Natal Plum has moderate growth, while Old Man's Beard grows slow.

💡 Pro Tips For Comparing These Plants

Natal Plum Care Tips

Natal Plum is primarily an outdoor plant and requires significant sunlight to thrive. Growing it indoors is challenging due to its high light needs and potential size. It needs well-draining soil, moderate watering, and occasional fertilization. Toxicity to pets is a major concern.

  • Provide at least 6 hours of direct sunlight daily for optimal growth and fruit production.
  • Water deeply but infrequently, allowing the soil to dry slightly between waterings.
  • Fertilize regularly during the growing season with a balanced fertilizer.
  • Prune regularly to maintain shape and encourage new growth.
  • Protect from frost in colder climates.
❄️ Winter: Reduce watering frequency during winter. Protect from frost if grown in containers by moving indoors or providing insulation. Avoid fertilizing during dormancy.
☀️ Summer: Ensure adequate watering during hot summer months. Provide afternoon shade in extremely hot climates to prevent leaf scorch. Fertilize regularly to support growth and fruit production.

Old Man's Beard Care Tips

Old Man's Beard is an outdoor lichen that is extremely difficult to cultivate indoors. It requires very high humidity, clean air, and specific lighting conditions. It is not a suitable houseplant and will likely die indoors.

  • Provide high humidity through regular misting or a humidifier.
  • Ensure good air circulation to prevent fungal growth.
  • Protect from direct sunlight, especially during the hottest part of the day.
  • Monitor for signs of drying out and adjust humidity accordingly.
  • Avoid using tap water for misting, as it can contain minerals that harm the lichen.
❄️ Winter: Protect from extreme cold and drying winds. Ensure adequate humidity.
☀️ Summer: Provide shade during the hottest part of the day. Increase humidity if necessary.

⚠️ Common Problems & Solutions — Plant Care Comparison

Natal Plum

Common Issues: Scale insects, mealybugs, root rot, lack of fruit production indoors.
Solutions: Scale/Mealybugs: Treat with insecticidal soap or neem oil. Root rot: Improve drainage and reduce watering frequency. Lack of fruit: Ensure adequate sunlight and pollination.

Old Man's Beard

Common Issues: Drying out, air pollution, lack of humidity, fungal infections.
Solutions: Increase humidity through misting or humidifiers. Ensure good air circulation. Treat fungal infections with appropriate fungicides (though this is difficult to do without harming the lichen).

❓ Frequently Asked Questions — Comparing These Plants

Natal Plum

What are the light requirements for Natal Plum?

Natal Plum requires ample sunlight to flourish and produce its characteristic blooms and fruits. Ideally, it should receive at least 6 hours of direct sunlight per day. In regions with intense sunlight, particularly during the hottest part of the day, providing some afternoon shade can prevent leaf scorch.

How do I care for Natal Plum?

Natal Plum thrives in full sun to partial shade. Ensure at least 6 hours of sunlight daily for optimal flowering and fruit production. Water thoroughly when the top inch of soil feels dry, allowing excess water to drain. Avoid overwatering, which can lead to root rot. Maintain moderate humidity, especially indoors.

How do I propagate Natal Plum?

Natal Plum can be propagated through stem cuttings. Take 4-6 inch stem cuttings from healthy, non-flowering shoots in spring or summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in a well-draining potting mix. Keep the soil moist and provide bright, indirect light. Rooting typically occurs within 4-8 weeks.

Old Man's Beard

What are the light requirements for Old Man's Beard?

Old Man’s Beard thrives in bright, indirect light. Direct sunlight can scorch its delicate foliage, causing it to dry out and turn brown. The ideal location is near an east- or west-facing window where it receives filtered sunlight. If you’re using artificial light, provide it with several hours of fluorescent or LED grow lights daily.

How do I care for Old Man's Beard?

Caring for Old Man’s Beard is relatively simple, but understanding its needs is crucial for its health and longevity. Place it in a location with bright, indirect light. Avoid direct sunlight, which can scorch the delicate foliage. Water by misting the plant thoroughly 2-3 times a week, or soaking it in water for 15-30 minutes every 1-2 weeks. After soaking, gently shake off excess water to prevent rot.

How do I propagate Old Man's Beard?

Old Man’s Beard is primarily propagated through pups, or offsets, that grow from the main plant. Once a pup reaches about one-third the size of the mother plant, it can be carefully separated. Gently pull or cut the pup from the main strand, ensuring you don’t damage either plant.

Last updated: May 2, 2026 — Plant care data reviewed and verified by our editorial team.