List of Fire-Resistant Plants that are also Drought-Tolerant

Why are Fire-Resistant Plants important?

Fire-resistant plants started gaining a lot of attention recently as extreme wildfires continue to devastate more area in one year than ever before in recorded history.

According to Congressional Research Service, in United States alone,

From 2013 to 2022, there were an average of 61,410 wildfires annually and an average of 7.2 million acres impacted annually. In 2022, 68,988 wildfires burned 7.6 million acres. Over 40% of those acres were in Alaska (3.1 million acres). As of June 1, 2023, around 18,300 wildfires have impacted over 511,000 acres this year.

Due to accelerating climate change and the increase in quantity and intensity of extreme weather events, and specifically wildfires, questions come up on how we can better protect ourselves, our families, and our communities.

Specifically in California, we are constantly living with the threat of wildfires. It is not a question of if, but a question of when the next major wildfire will start. We need to be prepared.

Fire-resistant drought-tolerant landscaping plays a crucial role in the fire prevention strategy.

Here in California, we have an additional complication of extreme drought and water shortage, which means that most un-irrigated or under-irrigated landscapes contain mostly brush that is completely dry and highly flammable.

We cannot increase irrigation because we want to conserve water and we cannot let plants dry out because that will make them a fire hazard.

Thus we find ourselves in a double-bind, looking for fire-resistant drought-tolerant plants.

To make things even more challenging, we can elevate to our mission to not only protect humans and our residential areas but also help protect the wildlands. 

We can accomplish this goal by creating sustainable and drought-tolerant fire-wise gardens that also limit the use of potentially harmful chemicals such as fertilizers and pesticides, and also avoid invasive plant species.

According to Fire Safe Marin, the idea is to surround the house with things that are less likely to burn while being beautiful and low maintenance.

When building homes in wildfire-prone areas, fire safety must be the first major consideration in landscape design.

Fortunately beautiful, low maintenance, fire-resistant drought-tolerant plants do exist!

In this article we will discuss:

• What are fire-resistant plants? Fire-proof vs. Fire-resistant.
• How to choose the right fire-resistant plants?
• Permaculture design for fire safety?
• List of fire-resistant plants.
• How to use fire-resistant plants to minimize the risk of the wildfires on our residential areas, farms, and orchards?
• What is fire-resistant landscaping?
• Can non-fire-resistant plants be used in firesafe landscape?

What are fire-resistant plants? Fire-proof vs. Fire-resistant.

Any plant species can burn. No plant is fire-proof.

According to https://defensiblespace.org, fire-resistant plants are those that do not readily ignite from a flame or other ignition sources. These plants can be damaged or even killed by fire; however, their foliage and stems do not significantly contribute to the fuel and fire’s intensity.

The goal is to have plants that will not spread the fire or make it larger.

There are several factors that influence the fire-resistant characteristics of plants, such as leaf moisture content, shape and size of the plant, presence of dead material, and chemical content of the sap.

We need to choose high-moisture plants that grow close to the ground, have a low sap or resin content, are drought-tolerant, and are easy to maintain.

Why choose high moisture plants for fire-safe landscape?

High moisture plants such as succulents and fruit trees are much harder to ignite. They will not only not contribute to the fire, but might actually slow it down. The fire wants to follow the path of least resistance and high moisture plants put up a lot of resistance. Succulents, for example, are often used to create a fire-break.

During latest wildfires in San Diego County, residents’ house was saved due to a large agave in their driveway. Agave was scorched on one side but the house was unharmed. Their neighbor’s house was completely destroyed due to the fire climbing a bougainvillea vine next to the entryway.

Why are low to the ground plants preferred?

This prevents ladder fuels (fire jumping from flammable ground cover to shrubs to shorter trees to taller trees) so a surface fire cannot reach the tree crowns.

Why choose low sap or resin content plants for fire safety?

Avoiding plants with gummy sap, high resin and oil levels, and leaves that are aromatic when crushed, is important because those oils and resins are often highly flammable.

Eucalyptus is an example of high oil content tree which is highly flammable. Eucalyptus drops much more debris than native California trees, which creates a perfect combination of oxygen and fuel. Eucalyptus trees are called “gasoline trees” in Australia for their tendency to explode in fireballs at very high temperatures. They drop far more flammable litter per acre than native trees and their embers stay lit longer and fly farther than embers from other vegetation.

Why do fire-safe plants have to be be drought-tolerant?

Since climate change and extreme drought are our new reality, we need to be operating under an assumption that more and more restrictions on irrigation will be implemented in the future. We don’t want to create a beautiful fire-safe landscape only to have our lovely carefully chosen plants turn into flammable brush due to water shortage.

Why do fire-safe plants have to be easy to maintain?

A key question to ask is ‘how easy is it to maintain this plant? Look critically at any plant that can harbor leaf litter and embers when blown in.

How to choose the right fire-resistant plants?

Because no list of fire-resistant plants will ever be complete and all-inclusive, it is useful to be able to look at any plant and decide whether it belongs in a firesafe landscape.

Any plant that is dying or dead, over-aged, water starved, infested by pests, or improperly cared for is more flammable.

For a fire-resistant plant you are looking for the absence of the following characteristics which would make the plant highly flammable:

Fine, dry, or dead material with-in the plant, such as twigs, needles, and leaves, loose or papery bark.

Does the plant look dry? Look carefully.

The plant might look green and healthy, however, when you look inside the branches, close to the trunk, you might see that the green new leaves are only on the outside, while inside of the tree or shrub is composed of dry fine branches. This is especially true for many drought-tolerant California natives which develop new growth on the outside only.

This is the case of drought tolerant plant not being fire-safe.

Leaves, twigs, and stems contain volatile waxes, sap, or oils. If the bark or leaves of the plant have a strong aroma or feels oily, it is probably flammable and a sign to stay away from this plant in a fire-safe landscape. Example is a great example of not fire-safe tree as described above.

In general, according to Fine Gardening, when deciding whether the plant is fire-safe, the following rules apply:

• Deciduous plants are less flammable than evergreens.
• Broad-leaf plants are less flammable than those with needle and blade like leaves.
• Moist and easily bent leaves are less flammable than stiff and leather like leaves.
• Thick leaves are less flammable than fine or thin leaves.
• Plants that produce a low amount of litter are less flammable than those that produce a lot of litter.
• Plants with sap that looks more like water are less flammable than plants with thick, gummy or resinous sap.
• Plants without fragrance are less flammable than plants with aromatic qualities.
• Plant leaves without hair (cilia) are less flammable than those with hair, including the underside of leaves.

List of fire-resistant plants:

Important Note:

All plants will eventually burn. There is no such thing as a fireproof plant. There are some plants that can retain moisture, even in dry areas, and are called fire resistant.

1. Succulents

Succulents are a diverse group of plants characterized by their ability to store water in their leaves, stems, or roots. This adaptation allows them to thrive in arid or semi-arid environments where water is scarce.

Succulents come in a wide variety of shapes, sizes, and colors, and they are popular for their unique and often striking appearance.

Some common types of succulents include:

• Aloe: Known for its medicinal properties, Aloe vera is one of the most well-known succulents. It has thick, fleshy leaves arranged in a rosette formation.
• Echeveria: Echeverias are popular ornamental succulents prized for their rosette-shaped foliage and vibrant colors.
• Aeonium are known for their striking rosette shapes and architectural growth habits.
• Ice Plant: this is a low-growing ground cover with succulent, green foliage and beautiful flowers in several colors. It requires very little watering and is fire safe.

Succulents serve as fire retardants to a large extent. Their ability to mitigate fire risk primarily lies in their water-storing capabilities and low flammability.

Water Content: Succulents, by nature, store water in their leaves, stems, or roots. This moisture content can act as a barrier against fire. During a fire, the water within succulents can help in reducing the temperature in the immediate vicinity, making it harder for flames to spread.

Leaf Structure: Many succulents have thick, fleshy leaves that contain water reservoirs. These leaves are less likely to ignite compared to plants with thinner, more flammable foliage.

Low Volatility: Succulents typically have low levels of volatile oils and resins, which are common in more flammable plants. This reduces the likelihood of them catching fire easily.

Succulents create a beautiful landscape that is high-moisture, non-invasive, drought-tolerant, low-maintenance and safe.

Prickly pears and aloes, for example, are not only beautiful but have added benefits of culinary and medicinal value.

When succulents and cactus can be successfully grown, there is no better plant at retarding a fire.

2. Geranium

The plants we commonly call “geraniums” are actually members of the genus Pelargonium. The genus is large and diverse, with approximately 280 species.

Geraniums can play a huge role in creating a stunning low-maintenance low-water fire-safe landscape because they “thrive on neglect.” They are supper easy to propagate by breaking cuttings 3-4 inches long and sticking them in the ground.

Here’s how geraniums may contribute to fire retardation:

Moisture Content: Geraniums, especially when well-watered (but even when they are not), contain moisture in their leaves and stems. This moisture can act as a barrier against fire, reducing the likelihood of immediate ignition. Even a geranium plant that is old and neglected will not usually not turn into dry sticks. It will remain green and moist on the inside.

Leaf Structure: Geranium leaves are relatively thick compared to some other plants, which may provide some resistance to ignition.

Flower Characteristics: Some geranium varieties have flowers with thick petals, which may offer additional protection against heat and flames

Geranium plants look amazing, add beautiful color and unforgettable scent.

3. Fruit Trees

Fruit Trees are often evergreen trees (especially in fire-prone areas like Southern California). They hold plenty of moisture.

Many fruit trees can tolerate drier conditions at least for some time. In addition they provide an abundance of food. So many options. So beautiful. So delicious.

Well-maintained fruit orchards make an excellent fire-break.

Fruit trees, like most plants, are not inherently fire retardant. However, there are  factors related to their growth habit and moisture content that affect their behavior and create a protective factor in the event of a fire:

Moisture Content: Fruit trees, especially when well-watered, contain moisture in their leaves, stems, and fruit. This moisture can act as a barrier against fire, reducing the likelihood of immediate ignition.

Leaf Structure: Some fruit trees have relatively thick leaves, which may provide some resistance to ignition compared to plants with thinner, more flammable foliage.

Fruit Characteristics: The fruit itself may contain moisture and may provide some additional protection against heat and flames compared to dry vegetation.

Canopy Density: The canopy of a fruit tree may affect the spread of fire. Dense canopies may reduce the penetration of flames to the ground, potentially slowing the spread of fire.

Rows of well-watered fruit trees make a great multi-functional addition to the fire-break.

4. Vegetable Gardens

In the spirit of Permaculture, we always try to find solutions that solve multiple problems.

An vegetable garden designed with fire-safety in mind can be part of a comprehensive defense plan.

We want to choose vegetables with high moisture content in their leaves and stems, such as tomatoes, cucumbers, and squash. These plants are less likely to ignite quickly.

We want to avoid highly flammable plants such as ornamental grasses, shrubs with volatile oils, and dry/dead vegetation within or near the garden.

We want to ensure proper irrigation to keep the soil and plants adequately hydrated. Well-watered plants are less likely to ignite and can serve as a barrier against fire.

We want to install drip irrigation or soaker hoses to deliver water directly to the base of plants, minimizing water loss through evaporation.

Perennial edible flowers such as nasturtium and artichokes are great examples of how an edible landscape can be functional, beatiful, and fire-resistant.

It is also important to remove any dead or diseases plant materials promptly.

5. Coastal Live Oak

Coastal Live Oak trees are important wildlife resources and have actually been
found to suppress fire, according to Fire Safe Council of San Diego County.

While no tree is entirely fireproof, coastal live oak exhibits characteristics that can contribute to fire safety:

Thick Bark: Coastal live oak trees have thick, corky bark that can provide some protection against fire damage. This bark helps insulate the tree’s inner tissues from heat and can prevent fire from penetrating deeply into the trunk.

Low Volatile Oils: Unlike some coniferous trees, coastal live oaks have lower levels of volatile oils in their foliage, which can reduce their flammability. This characteristic makes them less likely to ignite and sustain intense fires.

Deciduous Habit: Coastal live oaks are semi-evergreen to evergreen, meaning they retain their leaves year-round but shed them gradually. While not fully deciduous, this habit results in lower fuel loads compared to fully evergreen species, which can contribute to reduced fire risk.

Drought Tolerance: Coastal live oaks are adapted to Mediterranean climates and are relatively drought-tolerant once established. While drought-stressed trees may be more susceptible to fire damage, healthy, well-maintained coastal live oaks are better equipped to withstand fire.

Wildlife Habitat: Coastal live oaks provide habitat and food sources for a variety of wildlife, including birds and small mammals. Maintaining healthy oak woodlands can support biodiversity and ecosystem resilience, which can indirectly contribute to fire safety.

A live oak is one that “lives” through the winter; its leaves stay green all year, which is great for fire-safety.

Oaks have existed in California before the land was settled, but widespread deforestation due to the lumber and real estate industries has greatly reduced their numbers.

According to California state law, you cannot remove an oak tree from your property unless you apply for and receive the appropriate permit.

5. Toyon Tree

This small tree is very drought tolerant and provides red berry for months that are a favorite amongst many birds.

Toyon (Heteromeles arbutifolia), also known as California holly or Christmas berry, is a native shrub or small tree. While no plant can be considered entirely fireproof, toyon exhibits several characteristics that contribute to its fire resistance:

Moisture Content: Toyon typically maintains a relatively high moisture content in its leaves, especially during periods of active growth or after rainfall

Waxy Leaves: Toyon leaves are glossy and often coated with a waxy layer, which can act as a barrier against moisture loss and reduce the likelihood of ignition. This waxiness can also make it more difficult for flames to spread across the surface of the leaves.

Drought Tolerance: Toyon is adapted to Mediterranean climates and is relatively drought-tolerant once established.

Berries as Moisture Source: Toyon produces bright red berries that are attractive to birds and other wildlife. These berries can serve as a moisture source during dry periods, potentially increasing the plant’s resilience to fire.

Low Volatile Oils: Toyon is not known to contain high levels of volatile oils or resins in its foliage, which are common in some highly flammable plant species. This lower volatility contributes to its overall fire resistance.

Toyon is native to California and is well-adapted to the region’s climate and soil conditions. Using native plants like toyon in landscape designs promotes biodiversity, supports local ecosystems, and reduces the need for inputs like water and fertilizers.

With its attractive foliage, clusters of red berries, and evergreen leaves, Toyon can serve as both a functional and aesthetic element, providing beauty and utility to the landscape.

Ash

Sycamore

California Pepper Tree – Although they are not native to the state, California pepper trees are considered to be fire-resistant. This is because the trees have a high water content and their leaves are not as flammable as those of other trees.

Periwinkle

Bird of Paradise

Camelia

Hibiscus

Roses

Lilac

Maple

Birch

Ficus

Magnolia

Trumpet Vine

Jasmine

Wisteria

African Daisy

California Poppy

Lemonade Berry

Can Non-Fire-Resistant Plants be used in Firesafe Landscape?

According to Fire Safe Marin, you CAN make non fire-resistant plants much more resistant to ignition during a wildfire.

• Remove vegetation around the base of the trees
• Remove small-diameter lower limbs up to at least one-third of the tree’s height
• Remove limbs within 10 feet of the ground
• Remove all dead wood, peeling bark, and twiggy growth REGULARLY
• Provide canopy separation so that no limbs touch nearby trees or plants
• Remove all “ladder fuels

You also might want to ask yourself some questions: How far away is the plant from the house? Where does it fall on the defensible space plan? How big is it? How old is it? How critical it is to keep this tree versus the risk of fire?

work in progress… check back soon