How Much Light does my Plant Need?

by Kealey Bacic & Sarah Gardiner

Kealey has her own business, Iron Ivy ( where she spends her days designing homewares inspired by the natural world and is a horticulturist dabbling in greenhouse jungles.

Sarah is a horticulturist with a passion for edibles and cottage gardens.

1.Full Sun - Full sun exposure for at least 6 hours and withstanding up to 12 hours during warmer months.

2.Part Sun - Receiving 4-6 Hours of direct sunlight per day. Includes afternoon sun which is harsher on plants than morning sunlight.

3.Filtered Light - 6-12 hours of filtered/dappled sunlight (filtered through tree canopies outdoors, windows for indoors)

4.Bright Indirect - Ambient light that is not direct sun rays. Perhaps receiving 2-4 hours of direct sunlight but the majority of light is passed through a medium that softens light exposure or bounces off a reflective surface i.e. windows, shades, trees, walls etc. a good indicator of indirect light is blurry shadows at the brightest part of the day.

5.Full Shade - Less than 4 hours of indirect sun or all day sunlight through a shade cloth.

6.Med-Low Light - 2-3 hours of indirect, ambient light. Usually southern facing windows or located within 1-2 metres from a window. Minimal direct sunlight at any time of the day.

7.Low Light - Very low ambient light, minimal shadows cast. No direct sunlight at any time during the day, more than 2 metres from a bright window.

8.No Natural Light - no natural, usable light is present for plants to photosynthesise. 

Human existence is owed to plants, due to the fact plants can take sunlight and convert it into energy through the process of photosynthesis; fueling our life on the planet. So what do plants need in return from us? We know that all living plants need food and water. Light is food for plants and important to create sugars and energy, keeping them healthy and thriving.

The more light a plant is exposed to, the more sugars are generated and the faster it will grow. Having said this, it is still important to remember that not all plants can tolerate full-sun exposure, particularly many of our common indoor plants. For a lot of these plants, the sun in the height of Summer is too hot and can contribute to sunburn and stress; making it vital to achieve optimum lighting conditions without overdoing it.

Whether plants are grown indoors or out, it should be noted that a shady position outside is still brighter than a sunny windowsill inside. Light can bounce around outside from many different angles, whereas when growing plants indoors, light is more limited and generally only comes from one source such as a sunny window.

The phrase “bright light” is one that we’re used to hearing - but how much light does this actually mean? Plants like Monstera, Ficus and succulents are sun-lovers that are happiest when placed as close to a sunny window as possible. They are usually tolerant of direct indoor sun and light that might be reflected off glass windows.

Medium light or “indirect light” is generally light that has been diffused from the source, usually through curtains or perhaps growing on a south facing wall that might not receive direct sun. This kind of light might also be referred to as “dappled sunlight” and is great for plants such as Aroids, Maranta or Ctenanthe that have evolved to naturalise on rainforest floors, where they receive more protection from direct sunlight.

Finally, “low light” conditions refer to the darkest corners of your house. There are some plants that will tolerate these conditions when grown indoors, such as Spathiphyllum, Devil’s Ivy and ZZ plants. Generally speaking, these plants will be slower growing and require less water. As plants in these low lit spots are using less energy, they tend to survive in these conditions rather than thrive in them. One way to avoid a resident plant declining in a dark spot is to rotate them out monthly.

When navigating the light of your home, it is important to be mindful of this when making plant selections for specific spots. Always choose plants tolerant of low light for your darker corners and sun-loving plants for your brighter, more exposed positions. With apartment living becoming more prevalent, lack of natural light can always be combated with indoor grow lights with LED or fluorescent bulbs. Acclimating plants to grow under grow lights will expand the areas throughout your indoor space in which you can grow, while also extending the growing season and keeping your plants thriving through the winter months.

Check out the range of indoor grow lights on Urban Plant Grower’s website today and sign up to their mailing list to receive a 5% discount on your first order.