How far away can trees safely be planted from a house?

In our experience, subsidence usually occurs when high-water-demand trees are planted near houses built on shrinkable clay soils. The clay soil is the underlying cause of movement, but the tree’s large root system is what draws away essential moisture and causes the clay to shrink. Because the tree is the most obvious factor, it often becomes the immediate target for removal by the insurance industry.

However, you can box clever on this! Sometimes it is nice to have trees growing close to buildings to soften the hard landscape, as well as giving the opportunity for evergreen screening and privacy. There are two ways of achieving this without future ramifications.

1. Pruning: Controlling the Tree’s Size

The first way is to keep a tree tamed. Tilia euchlora (Aphid Resistant Lime) has the capacity to grow to 18 metres (60 feet) tall by the same across. Generally speaking, a root system matches the tree’s canopy to anchor it and provide the water and nutrients to support its crown. 

You can keep a mature tree such as Tilia euchlora to a mere 3 to 4.5 metres (ten to fifteen feet) high by routinely pruning back to the same point every winter, so reducing its need to produce a problematic root system to sustain it. This is sometimes referred to as pollarding. Alternatively, you can pleach or espalier the crown back each year to a one-dimensional frame for screening or formal aesthetics, which gives you the same effect. 

The drawback is that your tamed tree will want to revert to its normal size whenever it gets the opportunity to do so! Tree taming requires routine yearly maintenance every winter.

2. Selection: Choosing Small Trees

The second way to safely plant trees close to houses and buildings is to choose trees with the capacity to grow no more than 6 metres (20 feet) at maturity. You would be best considering a species which is half shrub and half tree, such as:

• Photinia Red Robin
• Ligustrum lucidum ‘Excelsum Superbum’
• Ligustrum japonicum

These small garden trees are excellent for screening as they are also evergreen. In general, the best practice is, the more distance you can allow when planting, the better, to be safe. We recommend pruning these types of trees to keep them full and dense, particularly if you are using them for screening.