Fire-wise yards
Defensible space in California
Defensible space is the buffer you keep between your home and the plants, mulch, and structures around it — space that slows a wildfire and, just as important, keeps wind-blown embers from catching against the house. In California's high fire-hazard areas it isn't optional: PRC 4291 requires 100 feet of it (or to your property line). Here's what goes in each zone — and the catch most low-water plant lists skip.
The three zones
Defensible space is worked in three zones, innermost first. Zone 0 is about materials (what's on the ground); Zones 1 and 2 are mostly spacing and clearing.
Ember-resistant zone
Noncombustible. This is the highest-priority zone — wind-blown embers pile against the wall, and most homes that burn are lost to embers, not a wall of flame.
Do
- Gravel, crushed rock, decomposed granite, pavers, concrete, or bare mineral soil as ground cover
- Keep the band clear right against the siding, under windows, and under the first 5 ft of deck
Keep out
- No bark or wood mulch, no rubber mulch
- No plants or grass against the wall — not even low-water ones
- No stored firewood, furniture, or wood fences/gates touching the house
Lean, clean & green
Reduce fuel and keep what's there healthy and spaced so fire can't climb or carry toward the house.
Do
- Space plants and shrubs so flames can't jump between them
- Keep plants watered and remove dead leaves, branches, and litter
- Keep combustible mulch shallow and broken up; prune low tree limbs
Keep out
- No dead or dying vegetation
- No 'ladder fuels' — shrubs under tree canopies that let fire climb
Reduce fuel
Thin and space the landscape out to the property line (or 100 ft) so an approaching fire drops to the ground and slows.
Do
- Mow annual grass down to 4 inches
- Space tree canopies and remove ladder fuels
- Clear fallen leaves, needles, and dead branches
Keep out
- No continuous beds of fuel that let fire run toward the house
Fire-resistant isn't fireproof
This is the mistake that undoes a lot of well-meant low-water landscaping: several classic drought-tolerant plants — juniper, rosemary, eucalyptus, pampas grass — are actually highly flammable. Low water use says nothing about how a plant burns. Nothing combustible belongs in the 0–5 ft Zone 0, no matter how little it drinks. Save the low-water plants for Zone 1 and beyond, spaced and maintained.
Size your Zone 0
Ready to plan it? The Defensible Space Tool sizes the 0–5 ft ember zone around your home and gives you the gravel/rock quantity and cost. From there, price the rest in the Material Calculator, plan the planting in the Lawn-Conversion Planner, or see water, fire, and cost together on the Resilient California Yard hub.
Defensible space — FAQs
Do I need defensible space, and how far out?
If your home is in a State Responsibility Area or a High or Very High Fire Hazard Severity Zone, California's PRC 4291 requires 100 feet of defensible space (or to your property line). Look up your address on the CAL FIRE Fire Hazard Severity Zone map, and confirm the specifics with your local fire authority.
What is Zone 0 and what can I put there?
Zone 0 is the ember-resistant band from 0 to 5 feet around your home — the highest-priority defensible-space zone, because wind-blown embers pile against the wall. California fire guidance calls for noncombustible ground cover here: gravel, crushed rock, decomposed granite, pavers, concrete, or bare mineral soil. Keep out bark and wood mulch, rubber mulch, plants and grass against the wall, stored firewood or furniture, and wood fences or gates that touch the house within the first 5 feet.
Is the Zone 0 rule law yet?
Not statewide, yet. California's Board of Forestry approved the Zone 0 (0–5 ft ember-resistant) regulation in 2026; it's in final state review and will phase in over the next few years for existing homes, with new construction first. Some local jurisdictions (San Diego, for example) already apply it to new permits, and it's smart to get ahead of it regardless. Check your local fire authority for what applies to your property now.
Are drought-tolerant plants fire-safe near the house?
Not automatically — and it's the catch most low-water plant lists skip. Fire-resistant is not fireproof, and several classic drought-tolerant plants (juniper, rosemary, eucalyptus, pampas grass) are actually highly flammable. Nothing combustible belongs in the 0–5 ft zone regardless of how little water it needs. Save the low-water plants for Zone 1 and beyond, spaced and maintained.
This is a plain-English planning guide, not a compliance determination. Requirements vary by location and change over time — look up your address on the CAL FIRE Fire Hazard Severity Zone map and confirm what applies to you with your local fire authority.