Is my garden a fire hazard?
Common yarrow is one of our most fire-resistant native plants. Photo: Peter Stenzel / flickr, licensed under CC BY-ND 2.0
It’s a new fact of life here in the WUI that we have to be prepared for wildfire. There are many ways to go about that but among the most important is what you plant around your house. The choices you make on your home landscape and in your garden influence how safe your house is should a wildfire come through.
When engulfed in flames, some plants throw more sparks than others.
Now there’s an easy way to tell which plants are the least likely to throw embers. That tool is called CSU Plant Flammability Index. Thank you, science.
Generally, according to CSU, plants are less flammable if they are:
Low growing
Drought-tolerant
Have high moisture content (green stems)
Low in resins
Have a compact growth habit
The opposite is true for the opposite attributes. Plants high in resins (such as evergreens like junipers and spruce trees) with woody stems and a branching habit are the least flame resistant. Not to say those plants can’t be useful and beautiful in a landscape (with the proper design techniques), you just don’t want them anywhere within 20 feet of your house.
Chose low-flammability plants wisely and plant them sparsely if close to your house (but never closer than 5 feet). For a more indepth look at landscaping in the WUI, attend one of our free, expert-led workshops.
Free Fire-Wise Gardening Workshops in 2025
April 8, 2025, 5:30-7PM, Louisville Rec Center. RSVP here
April 22, 2023, 6-730PM, Lafayette Public Library. RSVP here
The workshop is geared toward DIY gardeners who want to take on a season-size project to increase the fire-defensibility of their landscape. All participants will leave with a fire-wise planting template and everyone who attends is eligible for a random drawing for five, 50-plant kits that follow the fire-wise template.
