The olive tree root system is not invasive like some other trees you might worry about. Olive roots stay near the surface and spread outward rather than pushing deep into the ground. They won't crack your foundation or lift your sidewalk the way willows or poplars can.
Are olive roots invasive enough to damage your patio? Not in my experience over eight years of growing. I planted an Arbequina just six feet from a brick patio edge. The pavers look the same today as they did when I laid them. No heaving, no cracks, no problems at all from those roots.
Research from SCIRP shows that 70% of olive roots stay in the top 24 inches (60 cm) of soil. The roots spread out wide to catch rain in their dry home climate. They don't need to push deep because olives evolved where water sits near the surface after storms.
Olive roots grow long but stay fine and fibrous in nature. By year six a single tree can have about 33.9 kilometers of total root length. That sounds like a lot but these are thin hair-like roots. They soak up water and nutrients without the thick woody roots that damage structures.
The olive tree planting distance from buildings depends on the variety you choose. Standard trees need to sit 10 to 15 feet (3-4.5 meters) away from foundations. This gives the canopy room to spread and keeps falling olives off your roof. Dwarf varieties can go closer since they stay smaller in size.
Sidewalks and driveways need less clearance than buildings do. You can plant a standard olive 8 to 10 feet from walkways without worry. I have a tree that close to my front path and the concrete has stayed flat. The roots spread under the path but they're too small to lift anything.
Pools and septic systems deserve more care when you pick a planting spot. Keep trees 15 to 20 feet away from pool edges and drain fields. While olive roots won't crack pipes they will find any water source they can. You don't want them clogging your septic lines over time.
Plant your olive with confidence near most structures in your yard. The roots behave much better than many common landscape trees do. Just give standard trees enough room for their canopy and keep them away from underground utilities. Your hardscaping will stay intact for years to come.
Read the full article: Growing Olives: Step-by-Step Plan for Home Gardeners
