Honeylocust 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.

Honeylocust

Honeylocust

Gleditsia triacanthos

VS
Old Man's Beard

Old Man's Beard

Usnea spp.

Honeylocust

Honeylocust

Gleditsia triacanthos

Honeylocust is a deciduous tree typically reaching 30-70 feet in height. It is known for its rapid growth and adaptability to various soil conditions. While some varieties have long, sharp thorns on the trunk and branches, thornless cultivars are also popular. The leaves are pinnately or bipinnately compound, giving the tree a delicate, airy appearance. It is primarily an outdoor tree, valued for its shade, ornamental qualities, and tolerance of urban conditions. Attempts to grow it indoors are highly unlikely to succeed due to its size and light requirements.

Fabaceae Central North America
✨ Features: Drought tolerance, nitrogen fixation (to a small extent), attractive foliage.
📖 Read Complete Honeylocust 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 Honeylocust Old Man's Beard
Light Full sun (at least 6 hours of direct sunlight daily) Bright, indirect light outdoors. Full sun can scorch it in dry conditions.
Watering Water deeply 1-2 times per week during the first year, then as needed based on rainfall and soil moisture. Dependent on environmental humidity; mist when dry
Humidity 30-50% 60-90%
Temperature 10-30°C 5-25°C
Care Level Expert Expert
Growth Rate Fast Slow
Max Height Not applicable for indoor growing; 30-70 feet outdoors. Variable, up to several feet long depending on the species and environment.
Pet Safety ❌ Toxic To Pets ✅ Safe
Soil Well-drained soil; adaptable to various soil types including clay, loam, and sand. Does not grow in soil. Attaches to tree bark or other surfaces.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 1-2 hours per month (primarily for pruning and monitoring for pests/diseases) 5 minutes weekly (for misting if needed).

🔬 Botanical Information — Comparing These Plants

Honeylocust

Scientific Name Gleditsia triacanthos
Family Fabaceae
Native To Central North America
Also Known As Honeylocust, Honey Locust, Sweet Bean
Leaves The leaves are pinnately or bipinnately compound, meaning they are divided into multiple leaflets. The leaflets are small, oval-shaped, and have a smooth texture. The foliage is typically a bright green color, turning yellow in the fall.
Flowers Honeylocust trees produce small, greenish-yellow flowers in the spring. The flowers are not particularly showy and are often hidden among the foliage. Flowering is not relevant for indoor growing, as the tree cannot thrive 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

Honeylocust

Height Not applicable for indoor growing; 30-70 feet outdoors.
Spread Not applicable for indoor growing; 30-40 feet outdoors.
Growth Rate Fast
Growth Pattern Honeylocust trees have an upright, spreading growth habit, forming a rounded or irregular crown. They typically develop a single trunk with branching limbs.

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

Honeylocust

Methods: Seed, Root cuttings, Grafting

Difficulty: Moderate

Tips: Seeds require scarification and stratification before planting. Root cuttings should be taken in late winter. Grafting is used to propagate specific cultivars.

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

Honeylocust

Honeylocust trees are known for their rapid growth and adaptability to various soil conditions. Thornless varieties are popular for landscaping due to their ease of maintenance and lack of sharp thorns.

  • ✓ Provides shade and cooling in summer
  • ✓ Enhances property value with its attractive appearance
  • ✓ Supports local wildlife by providing habitat
  • ✓ Contributes to soil health through leaf litter decomposition
  • ✓ Offers a sense of connection to nature
  • ⚠️ 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

Honeylocust

Repotting Not applicable for outdoor trees.
Pruning Prune to remove dead, damaged, or crossing branches. Shape the tree for desired form.
Fertilizing Apply a balanced fertilizer (10-10-10) in early spring for young trees. Mature trees generally do not require fertilization.
Seasonal Care In winter, protect young trees from frost damage. In summer, ensure adequate watering during dry periods. Prune in late winter or early spring before new growth begins.

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

Honeylocust

Full sun (at least 6 hours of direct sunlight daily)

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

Honeylocust

Water deeply when the top few inches of soil are dry, especially during the first few years after planting. Mature trees are drought-tolerant. Overwatering can lead to root rot, indicated by yellowing leaves and a decline in overall health. Underwatering results in leaf drop and stunted growth.

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

Honeylocust

Temperature: 10-30°C

Humidity: 30-50%

Old Man's Beard

Temperature: 5-25°C

Humidity: 60-90%

🤔 Which Plant Is Right For You?

Honeylocust

Honeylocust

Gleditsia triacanthos
Care: Expert Time: 1-2 hours per month (primarily for pruning and monitoring for pests/diseases) Beginner: No

Landowners seeking a fast-growing shade tree for large properties.

✅ Choose This Plant If...

  • You need a fast-growing shade tree for a large area.
  • You want a tree that tolerates a variety of soil conditions.
  • You are looking for a tree with attractive, delicate foliage.
  • You need a tree that is relatively drought-tolerant once established.
  • You want a tree that provides some nitrogen fixation to the soil.

❌ Skip This Plant If...

  • You have a small yard or limited space.
  • You are looking for an indoor plant.
  • You have pets that might ingest the seed pods.
  • You prefer a low-maintenance, slow-growing tree.
📍 Ideal Location: Outdoor landscape, large yard, park
🎨 Style: Natural, Rustic, Traditional
🏠 Apartment Friendly: No
⚠️ The seed pods and seeds contain glycosides that can be toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset, such as vomiting and diarrhea.
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

📈

Honeylocust has fast growth, while Old Man's Beard grows slow.

💡 Pro Tips For Comparing These Plants

Honeylocust Care Tips

Honeylocust is an outdoor tree and is not suitable for indoor growing. It requires full sun, well-drained soil, and ample space to grow. Indoor attempts will likely fail due to insufficient light and space.

  • Choose a thornless variety for easier maintenance and safety.
  • Water deeply and regularly during the first year to establish a strong root system.
  • Prune regularly to maintain shape and remove dead or damaged branches.
  • Monitor for common pests and diseases and treat promptly.
  • Mulch around the base of the tree to retain moisture and suppress weeds.
❄️ Winter: Protect young trees from frost damage by wrapping the trunk with burlap. Water sparingly during periods of drought. Prune in late winter or early spring before new growth begins.
☀️ Summer: Ensure adequate watering during dry periods. Monitor for pests and diseases and treat promptly. Provide shade for young trees during the hottest part of the day.

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

Honeylocust

Common Issues: Webworm infestations, Canker diseases, Spider mites, Powdery mildew
Solutions: Treat webworms with Bacillus thuringiensis (Bt) or insecticidal soap. Prune out cankered branches. Control spider mites with miticides or insecticidal soap. Apply fungicides to prevent powdery mildew.

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

Honeylocust

What are the light requirements for Honeylocust?

Honeylocust thrives in bright, indirect light indoors. Insufficient light can lead to leggy growth and sparse foliage. A location near an east-facing or west-facing window is ideal, providing ample light without the harshness of direct sun. South-facing windows may require a sheer curtain to filter the light, especially during the hottest part of the day. If natural light is insufficient, supplement with grow lights to ensure the plant receives adequate illumination. Rotate the plant regularly to ensure all sides receive equal light exposure. Observe the plant for signs of light stress, such as pale leaves or stunted growth, and adjust its location accordingly.

How do I care for Honeylocust?

Caring for a Honeylocust indoors requires attention to its specific needs. Provide bright, indirect light, avoiding direct sunlight that can scorch the leaves. Water thoroughly when the top inch of soil is dry, ensuring good drainage to prevent root rot. Use a well-draining potting mix specifically formulated for trees or shrubs. Maintain moderate humidity levels, especially during dry winter months. Fertilize monthly during the growing season (spring and summer) with a balanced liquid fertilizer diluted to half strength. Prune regularly to maintain the desired shape and size, removing any dead or crossing branches. Repot every 2-3 years, or when the plant becomes root-bound, using a slightly larger pot. Protect from drafts and sudden temperature changes. Monitor for pests like spider mites or aphids and treat promptly if detected. Rotate the plant regularly to ensure even growth.

How do I propagate Honeylocust?

Honeylocust can be propagated through stem cuttings or air layering. For stem cuttings, take a 4-6 inch cutting from new growth in spring or early summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist in a humid environment, such as a propagation dome or plastic bag. Roots should develop in 4-6 weeks. For air layering, select a healthy stem and make a small incision. Apply rooting hormone to the incision and wrap it with moist sphagnum moss. Cover the moss with plastic wrap and secure it with tape. Once roots are visible through the plastic wrap, cut the stem below the roots and pot it up.

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 5, 2026 — Plant care data reviewed and verified by our editorial team.