Does Outdoor Lighting Harm Trees?

Updated June 26, 2023

Does Outdoor Lighting Harm Trees?

With our long winter nights, outdoor lighting in Oakville and Burlington is as practical as it is pretty. However, some North American scientists have raised concerns that artificial night lighting can have a negative impact on trees. Here is what you should know about outdoor lighting and how you can maintain healthy trees while maximizing safety and highlighting your property’s attractive features.

Does outdoor landscape lighting harm trees?


Know your facts

Trees need light to survive. The type of light (the wavelength or colour), the brightness, and the duration (how many hours) of light over the course of a day all affect tree growth. Certain trees rely on the amount of light in a day to know when to grow, flower, seed, or go dormant. Fewer hours of daylight in the fall signal trees to drop their leaves and stop growing.

If some trees are brightly lit at night with certain colours of light, there is a possibility that they may miss the cues that winter is approaching. They may fail to drop all their leaves in time, and risk damage from heavy snowfalls. Or they may not go fully dormant in time for winter and risk damage from cold. While the risk of tree damage is low, there are still many things you can do to optimize the health of more sensitive trees.

Know your trees

Outdoor lighting does not bother most tree varieties. Most conifers, such as spruce or pine trees, for example, are not affected by night lighting. Some deciduous trees—particularly flowering trees—may be more susceptible to certain types of night lighting. Since young trees grow faster, their growth cycle may be more affected by night lighting.

Nite Time Decor outdoor lighting experts can help you identify which trees are more sensitive to outdoor lighting and can design the appropriate lighting plans for your home.

Choose appropriate light fixtures

If you have a spectacular tree or trees that you want to have lit at night, fear not! There are many lighting options that won’t damage even the most sensitive trees. Some LED technology, for example, does not emit light in the red or infrared spectrum, which are the wavelengths of light that can impact tree dormancy and flowering.

Low, diffuse lighting can also be appropriate if you want to highlight outdoor landscape features. Down lights can be positioned to highlight plantings at the base of trees, which will avoid shining light on most of the tree leaves.

Consider timers and zones

Professional outdoor lighting takes into account both esthetics and safety. If you are lighting trees for esthetics, consider creating lighting zones and having the tree lighting shut off at a set time each day. You can keep other lighting zones—such as walkways and doorways—continuously lit for safety and security. This not only saves electricity, but also minimizes any effect outdoor lighting may have on surrounding trees.

Create a dynamic lighting design

Designing for beauty, safety, security, and tree heath is a complex business. Why not let the experts in outdoor lighting help you create or update a lighting design that meets all your needs? For more information on how a Nite Time Decor landscape lighting expert can help you create a striking display for your home, contact us today or request a complimentary quote.