Written by Susan B.
Wildfire Season Plant Picks, Selecting Fire Resistant Plants in the garden
California’s typical wildfire season extends from May to October. Historically, the rainy season in November has meant the end of the wildfire season because most plants get too wet during the rainy season to burn. You may recall that in December 2020, wildfires were still burning vigorously in Southern California. Given the proper conditions, any plant can burn.
California’s Two Wildfire Seasons
According to Fengpeng Sun, an Assistant Professor of Geosciences at the University of Missouri in Kansas City, Southern California has two wildfire seasons. The first is from June to September, and it occurs because of warmer and drier weather. It is called the Western Fire Season, and its fires typically occur farther inland and in forests at higher elevations. The second fire season extends from October to April. The Santa Ana winds encourage fires, and wind-driven fires burn faster. They occur in places closer to densely populated urban areas and are responsible for substantial economic losses. Santa Ana winds create naturally drier conditions. The winds blow embers around, causing fires to ignite wherever the embers land.
The Pacific Horticulture Society offers two reasons for creating fire-safe landscapes.
- Minimizing the amount of flammable material close to your home.
- Creating open space to ensure that firefighters have an unobstructed path through which to bring their equipment.
The Distinction Between Fire-Safe and Fire-Resistant Landscaping
Having a well-maintained yard doesn’t necessarily make it fire-safe. A fire-resistant garden is one in which the careful placement of plants is combined to reduce or minimize fire spread. It is as vital to the fire safety of your property as your choice of plants.
Many of Southern California’s fire-resistant plants are also ideal because of their drought resistance.
What You Need to Know About Choosing Fire-Resistant Plants and Materials
- Use decks, patios, pathways, and stone walls to create fire-resistant zones.
- Fill in bare spaces with flower beds, gardens, ground covers, mulch, and rock to create fire barriers.
- Fire-resistant doesn’t mean fireproof. No plant is fireproof. Choose plants with high moisture content and look for low-growing plants with little to no sap or resin.
- Look for plants that have a low risk of ignition so they can act as a fire-retardant. Aloes, ice plants, and rock rose are good examples.
- Look for fire-resistant shrubs, including:
- Bush honeysuckle
- Hedging roses
- Shrub apples
Plant hardwood trees that tend to be less flammable, e.g., Oak, Sycamore and Southern Magnolia. Avoid conifers, including pines and firs, because they are highly combustible.
You shouldn’t expect to create a fire-resistant landscape by picking plants from a list of fire-safe plants. You need to embrace the practice of putting the right plant in the right place. This will help you build a robust landscape that can adapt to fire conditions.
Things to Consider When Looking for Fire-Resistant Plants
- The amount of oils, resins, and waxes any plant contains. These substances will make the area burn faster and harder. Plants with lots of oils, resins, and waxes are more flammable, and the resulting fires are more energetic and explosive.
- The amount of moisture the leaves of each plant have. Fleshy leaves hold water, so succulents are excellent for this purpose. The more moisture leaves can maintain, the greater the fire resistance.
- The plant’s growth rate. Faster growth makes a plant more prone to catching fire. Fast-growing plants need regular maintenance to keep them healthy and eliminate dead branches and dried-out leaves.
- How tall a plant gets at maturity. Taller plants catch fire more easily.
- Determine whether the plant has an open-growth structure. Plants with a dense structure are more prone to catching embers and igniting. That increases the likelihood of ignition from a surface fire.
- Figure out whether your plant sheds bark. Bark can become kindling for an explosive wildfire. Plants, shrubs, and trees that shed bark and branches require regular cleanup. Without frequent cleanups, you provide fires with abundant fuel for ignition on the ground.
- Plants, trees, and shrubs that drop big leaves or needles also require more regular maintenance – especially on the roof and gutters. Their presence there makes your roof more prone to catching fire – especially when intense winds blow fires around.
Two Fire-Resistant Plants to Consider for Your Southern California Garden
Big Berry Manzanita (Arctostaphylos glauca)
Big Berry Manzanita is one of 193 Manzanita species that are native to California. It grows in our states chaparral and coastal and inland hill woodland areas. It is an evergreen shrub that grows in an upright to upright columnar form. During the winter and spring, it produces clusters of urn-shaped narrow, white, or pink flowers. After flowering, plants produce light red edible fruits. The fruits on this cultivar are larger than those of any other Manzanita species. They are roughly 12-to-15 mm wide and are egg-shaped or round. Each fruit has a tough outer coat that conceals a thick pulp covering a mass of 3-to-6 nutlets. Seeds will only germinate after exposure to fire. It is not uncommon for loads of seedlings to emerge after fires. Not surprisingly, this species can survive for 100 years or more.
Big Berry Manzanita grows best in full sun. It needs to grow in soil that has medium to fast drainage. And once the shrub is established, it requires water no more often than once a month. It can reach heights of between 3.3-and-20 feet, and it can spread to a width of between 6-and-20 feet. It attracts bees, butterflies, and hummingbirds, which eat the nectar from flowers and other birds who eat the berries.
Lemonade Berry (Rhus integrifolia)
Lemonade Berry is variably considered a small tree or a shrub. When grown in inland areas, it can reach a height of between 10-and-30 feet, but it grows in a lower, more sprawling habit when grown along the coast, reaching mature heights of between 3-and-6 feet. It has leathery-textured evergreen leaves that emerge from reddish-colored twigs. It produces small pink flowers that bloom from February to May (during winter and spring.) After flowering, reddish to gray berries appear. The berries provide wildlife with an essential food source. Its thick, sprawling growth habit makes it an ideal habitat for sheltering animals.
Lemonade Berry grows in full sun or partial shade. It tolerates most soil types but prefers a pH level between 5.0 and 8.0. It has low to extremely low moisture needs. Once your plants are established, they won’t need summer irrigation more often than twice a month. Use Lemonade Berry to stabilize banks, for hedges, in a bird garden, or in areas where you want the deer-resistant plant.
We’ve highlighted two of California’s fire-resistant plants, but there are many more you can choose for your garden. The California Native Plant Society has a database of 7,988 plants that are native to the state. Two other fire-resistant plants to consider are California Fuchsia (Epilobium canum ssp. latifolium) and California Lilac (Bixby Bridge) (Ceanothus ‘Bixby Bridge.) We encourage you to come into one of our stores to see what we have in stock. Our garden experts can help you select fire-resistant plants that are best suited to your area.
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