North America Native Plant

Orange Lichen

Botanical name: Caloplaca ferrugineofusca

USDA symbol: CAFE8

Habit: lichen

Native status: Native to North America  

Orange Lichen: A Colorful Natural Wonder for Your Garden’s Stone Features If you’ve ever noticed bright orange or yellow patches decorating the rocks in your garden, you might have encountered the fascinating world of lichens. Orange lichen (Caloplaca ferrugineofusca) is one of North America’s native lichen species that adds unexpected ...

Orange Lichen: A Colorful Natural Wonder for Your Garden’s Stone Features

If you’ve ever noticed bright orange or yellow patches decorating the rocks in your garden, you might have encountered the fascinating world of lichens. Orange lichen (Caloplaca ferrugineofusca) is one of North America’s native lichen species that adds unexpected splashes of color to stone surfaces and rock gardens.

What Exactly Is Orange Lichen?

Before we dive deeper, let’s clear up what we’re actually looking at. Orange lichen isn’t a plant in the traditional sense – it’s actually a remarkable partnership between fungi and algae living together in perfect harmony. This symbiotic relationship creates those eye-catching orange and yellow crusts you see growing on rocks, stone walls, and other hard surfaces.

Unlike the flowers and shrubs we typically think about for our gardens, lichens like Caloplaca ferrugineofusca are completely different organisms that have their own unique role in the natural world.

Where You’ll Find Orange Lichen

Orange lichen is native to North America and naturally occurs across various regions of the continent. You’re most likely to spot it in areas with clean air quality, as lichens are incredibly sensitive to air pollution and serve as natural indicators of environmental health.

Identifying Orange Lichen in Your Garden

Spotting orange lichen is easier than you might think once you know what to look for:

  • Bright orange to yellow-orange coloration
  • Crusty, flat appearance that seems painted onto rock surfaces
  • Typically found on limestone, concrete, or other calcium-rich stone surfaces
  • Forms irregular patches or circular colonies
  • Feels rough and brittle to the touch

Is Orange Lichen Beneficial for Your Garden?

Absolutely! While you can’t plant orange lichen like you would a flower or shrub, its presence in your garden is actually a wonderful sign. Here’s why you should celebrate finding it:

  • It indicates good air quality in your area
  • Adds natural color and texture to stone features
  • Provides habitat and food for tiny insects and other small creatures
  • Contributes to the natural ecosystem without any maintenance from you
  • Creates authentic, weathered character on stone walls and rock gardens

How Orange Lichen Grows in Your Space

Here’s the thing about lichens – you can’t really grow them in the traditional gardening sense. Orange lichen establishes itself naturally over time when conditions are right. If you want to encourage lichens in your garden, focus on creating the right environment:

  • Use natural stone materials like limestone or concrete in your landscaping
  • Avoid using pesticides or chemicals that could harm these sensitive organisms
  • Ensure good air circulation around stone features
  • Be patient – lichens grow very slowly, sometimes taking years to become noticeable

Living Alongside Orange Lichen

The best approach to orange lichen is simply to appreciate it when it appears. Don’t try to scrub it off your stone walls or rock features – instead, consider it nature’s way of adding free, maintenance-free color to your landscape. These hardy little organisms will continue to thrive as long as your local air quality remains good and they have suitable stone surfaces to call home.

If you’re designing a rock garden or incorporating stone features into your landscape, keep in mind that over time, lichens like orange lichen may naturally colonize these surfaces, adding authentic character and a connection to the wild spaces where these organisms naturally thrive.

Orange Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Teloschistales

Family

Teloschistaceae Zahlbr.

Genus

Caloplaca Th. Fr. - orange lichen

Species

Caloplaca ferrugineofusca (Vain.) H. Magn. - orange lichen

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA