The Fire-Resistant Landscape: Plant Species & Characteristics to Consider

Plants are living organisms—they are reactive and dynamic, with each species requiring specific conditions to thrive. Recent devastating wildfires in Los Angeles have highlighted the importance of fire-resistant landscaping. In addition to considering various factors when selecting plants for a landscape, it's crucial for designers to think about how the design will respond to fire.

When designing fire-resistant landscapes, plant material is a key consideration. Like humans, plants contain a certain percentage of water. Water is one of the best defense mechanisms against fire. Plants have different ways of managing water depending on their genus and species and these mechanisms manifest in the form of plant structure. Some of these mechanisms provide better fire defense than others.

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Plant Characteristics to Look for When Selecting Fire-Resistant Plants‍

Succulent Tissues | Plants like cacti and succulents store water in their thick, fleshy leaves or stems. The tissues contain specialized cells that can retain water for long periods making them less susceptible to fire.

Waxy Coating (Cuticle) | The waxy coating, also known as the cuticle, helps reduce water loss through evaporation, keeping the leaves moist for longer periods.

Sparse Foliage | Plants with well-spaced small leaves may be less likely to spread fire by increasing heat dissipation. Sparse foliage allows heat to dissipate more quickly, making it harder for the plant to reach the temperatures needed to ignite.

Plant Characteristics to Avoid ‍

Leaf & Branch Shedding | Deciduous plants shed their leaves during dry seasons to conserve water and reduce transpiration. While this does not necessarily mean the plant itself is more flammable, it does require active management to remove dead plant material.

Volatile Oils or Resins | Certain plants, like eucalyptus, have high oil or resin content, making them more prone to catching fire.

Leaf Hairs (Trichomes) | Plants with trichomes (tiny hairs) can have varying levels of flammability depending on their overall structure and chemical composition. Trichomes can sometimes be flammable because they can dry out quickly and create additional surface area that might catch fire more easily

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As previously mentioned, fire resistance is just one of the many factors we must consider when selecting plants. Plants carry regional and cultural connotations that influence how people interpret them. For instance, palms are typically associated with tropical environments, however, different species of palms can grow in non-tropical locations and may feel more or less appropriate depending on the context.

Our office is based in Palm Springs, which shares many characteristics with Los Angeles, but each area often exhibits different planting approaches. To respect the unique planting approaches of each city, I've included a list of some of our favorite fire-resistant plant species suitable for Los Angeles and Palm Springs. While most of these species are not exclusive to one locale, they may feel more or less appropriate depending on different contexts and interpretations.

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Plant Species to Help Promote a Fire-Resistant Landscape

LOS ANGELES

Trees

• Quercus agrifolia - California Live Oak
• Platanus racemosa - Sycamore
• Lagerstroemia spp. - Crepe Myrtle
• Chitalpa x tashkentensis - Pink Chitalpa

Shrubs

• Ceanothus spp. - California Lilac
• Arctostaphylos spp. Manzanita
• Artemisia californica - California Sagebrush

Succulents & Cactus

• Agave attenuata - Foxtail Agave
• Crassula ovata - Jade Plant
• Aeonium arboretum - Tree Aeonium
• Opuntia ficus-indica - Prickly Pear

Perennials

• Eschscholzia californica - California Poppy
• Echinacea spp. - Coneflower
• Achillea millefolium - Yarrow

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PALM SPRINGS

Trees

• Parkinsonia florida - Blue Palo Verde
• Schinus molle - California Pepper Tree
• Acacia stenophylla - Shoestring Acacia
• Olea europaea ‘Wilsonii’ - Wilson Olive

Shrubs

• Sphaeralcea ambigua - Desert Globemallow
• Fremontodendron californicum - California Flannelbush
• Caesalpinia mexicana - Mexican Bird of Paradise
• Arctostaphylos spp. Manzanita

Succulents & Cactus

• Agave americana - Century Plant
• Aloe vera - Medicine Aloe
• Lophocereus schottii monstrosus - Totem Pole Cactus 
• Yucca gloriosa - Spanish Dagger

Perennials

• Salvia dorrii - Desert Sage
• Dalea capitata 'Sierra Gold’ - Sierra Gold Lemon Dalea
• Poliomintha maderensis ‘Lavender Spice’ -  Mexican Oregano