How Far Do Leylandii Roots Spread?

The leylandii species of plant are notorious for their fast-growing characteristics, with one of the tallest leylandii trees in the country reaching up over 100 feet. If they are  properly established, they can take up significant space uncontrollably unless appropriately maintained.

Of course, not when purchasing a hedge for your property you need not worry about your plant reaching such incredible heights, but you must be prepared for the roots to grow proportionally to the height of the hedge itself. There are many factors that determine the growth of the roots, such as the location of planting, soil type and height.

One major issue caused by the root spread of leylandii is that soil in the plant’s surrounding area risks becoming dry due to the moisture being withdrawn by the roots. The result of this can be found in the wilting of grass and even other plants in the area!

It is also not advisable to plant leylandii hedges directly near a house or building that has weaker foundations, especially if built over 50 years ago. Due to the fast-spreading nature of the root systems, planting one, or several hedges too close to an older building can put the foundations at risk of crumbling.

If you do choose to plant them near your building, we would recommend trimming the leylandii hedge down significantly twice a year, only after they have achieved their required heights.

For example, leylandii hedges that grow to about 4 or 5 metres high will have a root system that runs 2 or 3 metres deep. 

Please note that if you do decide to severely trim down a leylandii hedge, it is best done during the spring months. If done any other time of the year, the conifer plants may not recover at all. It is important not to cut the side growth back into completely bare branches as these will not regenerate. Be sure to leave some green foliage from which new growth will emerge. Alternatively, if you are more concerned about the plant root damage, it may be worth consulting with a gardening expert or a tree surgeon before choosing to pull up the roots, especially if you are concerned of damage to your property.

For more information on leylandii root spread, please visit our Knowledge Base, check out our product range or contact the Hopes Grove Nurseries team today!

Alternatively, we also have other articles relating to leylandii plants. From controlling honey fungus to feeding a leylandii hedge, our Knowledge Base has all the answers you need. Why not take a look?