Shrub gap calculator
Leave at least
12 ft
Quick numbers
| Rule | Number |
|---|---|
| Shrub gap, slope under 20% | 2 × shrub height |
| Shrub gap, slope 20–40% | 4 × shrub height |
| Shrub gap, slope over 40% | 6 × shrub height |
| Zone 0 plants apart | 1.5 × tallest height |
| Limb up trees | Lower 6 ft or ⅓ of height |
| Branches from roof / chimney | 5 ft / 10 ft |
| Hedges | Max 6 ft, 10 ft from house |
| Grass before it cures | Mow to 4 in. |
Worked example
A 3 ft shrub on a 30% slope falls in the 20–40% band, so leave 4 × 3 = 12 ft between shrubs. Plan for the plant’s mature size, not its size in the nursery pot.
Your agency may require more. Estimates only.
Fire-safe still needs a water budget. Validate your hydrozones, WUCOLS plant ratings and MAWA water budget, and get permit-ready compliance documents, at MWELO.com. For fuel-mod plant choices, see the MWELO fuel mod guide.