Confused about lighting? Not sure how much light your plant needs or where to put it? Read on as we shed some light on the subject.
Different types of plants require different light levels. There are a variety of factors that influence how much light a particular plant needs, including the species of plant, the environment in which it was grown, the climate where you live, and even the plant’s growth cycle (including dormancy). Light is typically measured two ways: 1) in quality (colour/wavelength), and 2) quantity (intensity).
One thing to keep in mind is that the darkest shade outdoors is still brighter than putting your plant in the sunniest window in your home. This is important to remember if you have any houseplants that you would like to move outside during the summer. When moving your plants outdoors, they must be acclimated gradually.
You can find a recommended light level for your individual plant by looking up your plant on our collections + care page. Please read below for more details on what each lighting description means.
Full sun refers to an extended period of unimpeded exposure to undiffused sunlight. Imagine a plant outside at high noon in the summer with no shade. The term full sun is used most often with plants that are intended to be grown outdoors. By contrast, bright and direct light refers to extended exposure to sunlight that may be diffused slightly through a window, while still allowing the plant’s foliage to be exposed to direct sunrays. Bright and direct light is a term used more commonly with indoor houseplants, but some growers may use these terms interchangeably.
Bright and direct light is the brightest, most intense light that can be experienced indoors. Typically, this comes from South and West facing windows. To give your plants this level of light, they must be situated as closely to the window as possible. Succulents, cacti, and Ficus are examples of plants that prefer this level of light. South windows tend to get the most light. Be advised that most houseplants can experience leaf burn with this level of light exposure, so indirect or diffused light is preferred.
Bright and indirect light is the most common type of light recommended for most houseplants in Canada and the US. Most commercially grown houseplants are tropical plants that prefer this kind of light. Bright light is particularly important for plants with colourful foliage, as sunlight often helps these plants maintain their vivid colours. However, even tropical plants that naturally require bright light can be burnt if they are exposed to extended periods of full sun or direct light without being acclimated gradually to higher levels of light exposure. Bright and indirect light is light that is lightly diffused or that which is reflected off another surface before reaching the plant. In northern climates, like in Canada and the Northeastern US, plants should be kept close to a bright window during the winter months to maximize sun exposure, but can be moved further away during the summer months. East windows are good sources of bright and indirect light because they get soft light exposure in the morning.
Medium light is the recommended amount of light for most “low light” houseplants. It consists of light that is diffused or indirect. A plant in a bright room several feet away from a window might be considered to have medium light. North-facing windows are also good sources of medium light because they don’t get direct light during the day.
Very few houseplants can thrive on low light. Low light generally means no direct sun exposure, and only minimal indirect light. Most houseplants that are labelled as “low light” actually thrive much better in medium light, but will tolerate lower levels of light to an extent. Some examples of plants that tolerate low light are ZZ plants, Dracaenas, and Peace lilies (spathyphyllum). If you’re looking to grow a plant that requires bright light in a space that has very little sun exposure, you should consider investing in a grow light to help supplement some of the missing light that your plant will need to grow and thrive.
All green plants, to some degree, need light. That’s because light is an integral part of photosynthesis, the process by which green plants transform light energy—in addition to water and carbon dioxide—into chemical energy or sugar that plants need to grow. Grow lights can be used to supplement that energy, but they do require a considerable amount of electricity.
There are several factors to consider before investing in a grow light, and many different types of light to choose from. LED and fluorescent lights are the most popular choice because they are more energy efficient and produce more light compared to heat than traditional incandescent lights. The colour spectrum that a light outputs is important, as most plants prefer full spectrum light. Flowering and fruiting plants prefer more red light waves than others. The amount of light required will depend on the size of your plant and how much space you wish to illuminate. Generally, you should consider 20 to 40 watts per square foot of growing space. Adjustable lights are helpful so that you can maintain a space between the plant and the light as it grows, to prevent burning. If you’re unsure, you can consult your local garden centre for more advice on a grow light set up for your specific space.
Windows on different sides of your dwelling can provide varying levels of light exposure. How much will vary depending on if you have any trees, buildings, or other objects diffusing the amount of sunlight that comes through your window. The four cardinal directions--north, south, east and west--use the rising and setting of the sun as reference points. South and west-facing windows provide the most bright and direct light. East windows are good sources of bright and indirect light. North windows have the least sun exposure and are best for medium light.
Dormancy refers to a period during a plant’s growth cycle in which growth slows. Dormancy is like plant hibernation: it protects plants by helping them rest and conserve energy during periods of stress like drought or cold temperatures. Dormant plants can typically survive on less sunlight than plants would otherwise need during their peak growing time. Most houseplants are dormant during the winter; however, some species thrive better during the colder and darker months. Haworthias, aeonium and aloes are examples of plants that are summer-dormant and grow mostly in fall, winter, and early spring.
Some plants thrive better than others outdoors. Where you live and where you put your plant is important. Since almost all houseplants are greenhouse-grown indoors, putting your plant in full sun after picking it up from the store is not recommended. Even sun-loving succulents can experience sunburn if exposed to full sunlight without being gradually acclimated to increasing sun exposure over a period of several weeks. In most parts of Canada & the US, succulent plants or large tropicals like palms that prefer bright light are the best suited for being kept outdoors during the summer months. The USDA plant hardiness zone map is a good indicator of whether or not a plant can be grown outdoors in your region. Most commercially grown houseplants are tropical or desert plants that will not survive frost or grow back after overwintering outdoors in sub-zero temperatures, preferring temperatures above 10 Celsius (50 Fahrenheit) at a minimum.
Important note: when putting your plant outdoors, please be aware that you are exposing it to pests that could hide in the soil. Check your plants before bringing them indoors.