Monkey Flower 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.

Monkey Flower

Monkey Flower

Mimulus aurantiacus

VS
Old Man's Beard

Old Man's Beard

Usnea spp.

Monkey Flower

Monkey Flower

Mimulus aurantiacus

Mimulus aurantiacus, commonly known as Sticky Monkey-flower, is a perennial shrub native to the California chaparral. It typically grows to 1-5 feet tall and wide, featuring narrow, sticky leaves. The plant is named for its bright orange, tubular flowers that resemble a monkey's face. It thrives in dry, sunny conditions and is well-adapted to drought. While primarily an outdoor plant, it is grown for its vibrant flowers and ability to attract pollinators like hummingbirds and butterflies. Indoor cultivation is challenging due to its high light requirements and need for well-draining soil.

Phrymaceae California and Baja California
✨ Features: Drought tolerance, attracts pollinators, deer resistant
📖 Read Complete Monkey Flower 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 Monkey Flower Old Man's Beard
Light Full sun to partial shade Bright, indirect light outdoors. Full sun can scorch it in dry conditions.
Watering Every 1-2 weeks, depending on sunlight and temperature Dependent on environmental humidity; mist when dry
Humidity 30-50% 60-90%
Temperature 15-27°C 5-25°C
Care Level Expert Expert
Growth Rate Moderate Slow
Max Height 0.3-1.5 meters (1-5 feet) outdoors, smaller indoors (if grown) Variable, up to several feet long depending on the species and environment.
Pet Safety ✅ Safe ✅ Safe
Soil Well-draining sandy or loamy soil Does not grow in soil. Attaches to tree bark or other surfaces.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly 5 minutes weekly (for misting if needed).

🔬 Botanical Information — Comparing These Plants

Monkey Flower

Scientific Name Mimulus aurantiacus
Family Phrymaceae
Native To California and Baja California
Also Known As Sticky Monkey-flower, Orange Monkey Flower
Leaves The leaves are narrow, lance-shaped, and sticky due to a resinous coating. They are typically 2-7 cm long and arranged oppositely along the stems. The color is usually a medium to dark green.
Flowers It flowers outdoors in spring and summer. The flowers are tubular, typically bright orange, and about 2-5 cm long. They have five lobes that resemble a monkey's face, hence the common name. Flowering is unlikely indoors.

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

Monkey Flower

Height 0.3-1.5 meters (1-5 feet) outdoors, smaller indoors (if grown)
Spread 0.3-1.5 meters (1-5 feet) outdoors, smaller indoors (if grown)
Growth Rate Moderate
Growth Pattern Sticky Monkey-flower is a shrubby perennial with an upright, branching growth habit. It typically forms a rounded shape and can spread to be as wide as it is tall.

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

Monkey Flower

Methods: Seed, stem cuttings

Difficulty: Easy

Tips: For stem cuttings, take 4-6 inch cuttings in spring or summer, remove lower leaves, and root in well-draining soil. Keep the soil consistently moist. Seeds can be sown directly in the garden in fall or started indoors in early spring.

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

Monkey Flower

The sticky resin on the leaves is a unique adaptation to drought conditions. The flower's shape is specifically adapted to attract hummingbirds for pollination.

  • ✓ Attracts pollinators like hummingbirds and butterflies
  • ✓ Provides vibrant color to the garden
  • ✓ Drought-tolerant, reducing water usage
  • ✓ Deer resistant
  • ✓ Supports native ecosystems
  • 🐾 Pet Safe

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

Monkey Flower

Repotting Not typically grown indoors, so repotting is not usually a concern. If grown in a container, repot every 2-3 years in spring.
Pruning Prune lightly after flowering to maintain shape and encourage bushier growth.
Fertilizing Low-phosphorus fertilizer, diluted to half strength, applied in spring and early summer only.
Seasonal Care In winter, reduce watering and protect from frost in colder climates. In summer, provide adequate water during dry spells and deadhead spent flowers to encourage continued blooming.

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

Monkey Flower

Full sun to partial shade

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

Monkey Flower

Water deeply when the top inch of soil is dry. Overwatering can lead to root rot, indicated by yellowing leaves and a musty smell. Underwatering results in wilting and dry, crispy leaves. Allow the soil to dry out slightly between waterings.

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

Monkey Flower

Temperature: 15-27°C

Humidity: 30-50%

Old Man's Beard

Temperature: 5-25°C

Humidity: 60-90%

🤔 Which Plant Is Right For You?

Monkey Flower

Monkey Flower

Mimulus aurantiacus
Care: Expert Time: 15 minutes weekly Beginner: No

Experienced gardeners in Mediterranean climates looking for a drought-tolerant, pollinator-attracting plant for their garden.

✅ Choose This Plant If...

  • You live in a Mediterranean climate with hot, dry summers.
  • You want to attract hummingbirds and butterflies to your garden.
  • You are looking for a drought-tolerant plant.
  • You appreciate vibrant orange flowers.
  • You have a sunny garden with well-draining soil.

❌ Skip This Plant If...

  • You live in a climate with cold winters and frequent frost.
  • You don't have a sunny location.
  • You are a beginner gardener looking for an easy-to-grow indoor plant.
📍 Ideal Location: Sunny garden or rock garden
🎨 Style: Natural, Southwestern, Mediterranean
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Mimulus species are generally considered non-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 Both safe ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

📈

Monkey Flower has moderate growth, while Old Man's Beard grows slow.

💡 Pro Tips For Comparing These Plants

Monkey Flower Care Tips

Sticky Monkey-flower is primarily an outdoor plant that requires full sun and well-draining soil. Indoor cultivation is challenging due to its high light needs. It is drought-tolerant once established but benefits from occasional watering during dry periods. Pruning after flowering encourages bushier growth. Indoor growing is difficult to achieve.

  • Provide full sun for optimal flowering.
  • Ensure well-draining soil to prevent root rot.
  • Water deeply but infrequently, allowing the soil to dry out between waterings.
  • Prune lightly after flowering to encourage bushier growth.
  • Avoid over-fertilizing, as this can lead to leggy growth.
❄️ Winter: In colder climates, protect from frost with mulch or move container plants to a sheltered location. Reduce watering during the dormant season.
☀️ Summer: Provide adequate water during dry spells. Deadhead spent flowers to encourage continued blooming. Protect from intense afternoon sun in extremely hot climates.

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

Monkey Flower

Common Issues: Root rot, powdery mildew, aphids
Solutions: Root rot: Ensure well-draining soil and avoid overwatering. Powdery mildew: Improve air circulation and treat with fungicide. Aphids: Spray with insecticidal soap or neem oil.

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

Monkey Flower

What are the light requirements for Monkey Flower?

Monkey Flowers require bright, indirect light for optimal growth and blooming. Direct sunlight can scorch the leaves, especially during the hottest part of the day. An east-facing window is ideal, providing gentle morning sun. A west-facing window can work, but be sure to provide shade during the afternoon. If growing indoors, supplement with grow lights if natural light is insufficient. Insufficient light can lead to leggy growth and reduced flowering. Rotate the plant regularly to ensure even light exposure on all sides. If the leaves start to look pale or yellowish, it may be a sign of too much light.

How do I care for Monkey Flower?

Monkey Flowers thrive in bright, indirect light. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Fertilize regularly during the blooming season with a balanced liquid fertilizer, diluted to half strength, every two to four weeks. Maintain moderate humidity levels, around 40-60%. Prune spent flowers to encourage new blooms. Repot in spring if the plant becomes root-bound, using a well-draining potting mix. Monitor for pests like aphids and spider mites, and treat promptly with insecticidal soap. Provide good air circulation to prevent fungal diseases. In winter, reduce watering and hold off on fertilizer.

How do I propagate Monkey Flower?

Monkey Flowers can be propagated through division, stem cuttings, and seed.

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 14, 2026 — Plant care data reviewed and verified by our editorial team.