The garden goes in after the build. That's normal — landscape and architecture happen on different timelines. But the assumption that landscaping is a separate, post-construction concern is what gets a lot of homes into trouble.

What you plant, where you plant it, and how you irrigate has more effect on the long-term structural performance of a residential build than almost any other choice you make as a homeowner.

Tree roots are persistent

Roots will travel a long way to find water. The ones that find it under your slab, against your footings, or inside your subsoil drain are difficult to evict and expensive to manage.

Specific guidance:

  • Before planting near the house, talk to an arborist or geotechnical engineer about appropriate species and distances. The cost of that conversation is a tiny fraction of the cost of removing a thirty-year-old tree that's lifted a footing.
  • Avoid moisture-aggressive species (figs, willows, eucalypts) close to the house unless an engineer signs off the distance.
  • Be careful with trees on the boundary. They are often older than the house and they have a head start on root spread.

Garden beds against the wall

Don't.

A garden bed pressed against an external wall combines three problems:

1. The soil retains moisture against your slab edge, which can migrate into the building and shows up as damp patches inside. 2. The soil level is often higher than the original ground level we built to, which means weepholes and sub-floor vents now sit below the dirt line and can't drain. 3. Roots from anything you plant in that bed go straight to the footing.

A perimeter of paths or paving around the house — even a 600 mm wide strip — is one of the cheapest, highest-leverage protections you can give the building.

Overwatering is a leak

Most homeowners think of irrigation as benign. It isn't, in the wrong place. A drip line that's been running for ten minutes a day for ten years against the side of a slab has put roughly 36,000 litres of water into ground that was supposed to stay dry-ish. That ground swells, contracts, swells, contracts. Over time, it moves the slab.

If your irrigation system runs near the house, get a landscape designer or arborist to map the zones and confirm none of them are pumping water into ground that doesn't want it.

Once you've planted

After landscaping is in:

  • Don't bury subsoil drain outlets, weepholes, or sub-floor vents under mulch or new paving.
  • If you add a retaining wall or a pool, get the existing drainage system mapped first so the trades doing the new work don't unknowingly cut through it.
  • After a major weather event, walk the perimeter. If a new wet patch has appeared somewhere, it's worth investigating. New patches are how problems first announce themselves.

The principle

The building was designed to perform with the ground around it doing certain things. Landscaping that respects those constraints lets the building age gracefully. Landscaping that ignores them is the most common reason an otherwise well-built home develops problems in years five, ten, or fifteen.

The garden is yours. The conversations to have first are with the people who know your specific build — that's us, plus a good arborist and a geotechnical engineer when the project warrants it.