Depth by what you're doing next
As a rule of thumb, you want the top of the remaining stump to sit below the depth of whatever will be disturbed above it.
- Lawn or turf: 150–200mm below soil level — enough for soil and root zone
- Garden bed or planting small shrubs: 200–300mm
- Paving, pavers or a path: 250–300mm plus a compacted base
- Concrete slab, driveway or foundation: full removal of the root plate, not just grinding
- Fence posts on the stump line: clear to post depth, typically 600mm+
- Planting a large replacement tree in the same spot: full removal
Why 150–300mm is the standard
Below about 150mm the stump is out of the root zone of new turf and grass, so the lawn establishes normally and you'll never know it was there. Push much past 300mm and the grinder wheel is fighting soil and stones rather than timber, which burns teeth and time without improving the result for a lawn.
That's why a standard residential grind is quoted at 150–300mm, and anything deeper is priced as removal work.
The bit most people miss: root spread, not depth
For big Auckland species — pohutukawa, liquidambar, plane, gum — the problem after grinding usually isn't depth, it's the surface roots running metres across the lawn. If you want a genuinely flat, mowable lawn, those need chasing back and grinding out too.
We quote the root run separately so you can see the cost and decide. On a re-turf job it's almost always worth it.
How much soil do you need to fill the hole?
A ground stump leaves a crater of mulch that will settle over the first few months. You add your own soil when you're ready to turf or plant. For a 500mm-wide stump ground to 250mm you're looking at roughly one to two barrow loads of soil.
Common questions
- How deep do you grind a stump for lawn?
- 150–200mm below soil level. That clears the root zone so new turf or grass seed establishes normally over the top.
- How deep does a stump need to be ground before concreting?
- Grinding alone isn't enough under concrete or a driveway — the stump and root plate should be excavated and the hole left clean for your builder to fill, otherwise the slab can settle and crack as the timber decays.
- Can you grind a stump deeper than 300mm?
- Yes, but past that point it's excavation work rather than standard grinding, and it's priced accordingly. Tell us what's going on the spot and we'll grind to the depth it actually needs.