Good Dirt How much sunlight do my indoor houseplants need to grow? Metal watering can sits next to potted plant in front of open sunlit window.

How much sunlight do my indoor houseplants need to grow?

Light can be a tricky factor in the health of your plant. Too much or too little and a plant's health will suffer. So, it's up to you to determine how much light is needed for it to thrive.

Being aware of how essential it is to the life of your plant, what light your plant seeks, the direction your house faces, and the effects of seasonal changes to light will guide your placement of the houseplant in your home. Let’s walk through each of these factors so your indoor jungle will become lush, strong and healthy. 

Why are light levels important for indoor plants?

Plants need light to fuel their growth. Your houseplants will require varying amounts of light to complete the fuel-growth-process called photosynthesis. Without light and nutrition most plants will eventually die. 

How Photosynthesis Works

A plant absorbs carbon dioxide from the air through tiny holes in its leaves, branches, stems, flowers and roots, water from the soil through its roots and light energy from the sun to perform photosynthesis. Light energy triggers a chemical reaction, breaking down carbon dioxide and water molecules and rearranging them to create sugar (glucose) and oxygen gas. Sugar is then broken down by the hardworking organelles called chloroplasts, which are most abundant in the cells of the plant’s green leaves, into energy to fuel the plant’s growth and repair. The oxygen gas produced by the plant goes back into the atmosphere via the same little holes that absorbed the carbon dioxide.

The Photosynthetic Process

Photosynthesis is a complex process with two stages. The first stage is a light-dependent reaction when photons from sunlight hit the plant’s leaf, galvanize the light-absorbing pigment chlorophyll and activate electrons. This divides water into oxygen and hydrogen ions. The second stage, a light-independent reaction, uses the energy from the light reaction to convert carbon dioxide into glucose through a series of chemical reactions that begin with 3-ribulose bisphosphate and end up with the same molecule, producing glucose in the process. The plant uses glucose in different ways. It can convert it into chemicals needed to grow plant cells like cellulose or starch that it can store until the plant needs to convert it back to glucose. It can break it down during respiration, releasing energy stored in the glucose molecules. A plant doesn’t need energy from the sun for respiration.

It is helpful to go ahead and determine the type of light you have in your home before deciding which plants you want. When observing light levels in your home, make note of these things:

  • Light Duration: the number of continuous hours of light in a 24-hr time period.
  • Light Intensity: the brightness of light. 
  • Light Quality: the color of light (yellow, orange, etc)

Knowing these three things will help you pick the right plants that can thrive and flourish in your space. 

Light types on plant labels

Once you have a handle on the light characteristics of your home (duration, intensity, and quality), now the true fun begins! It’s time to pick which plant calls to you while making sure you choose one that has the best chance of survival with the light amount that is going to be available. 

You can research plants before you buy online or head to the store for an idea of what you’re looking for, and in most cases plant labels already have the plant’s light requirement already located on the label itself. 

Common labels for houseplants will have info like: 

Types of Light Types of Houseplants
Direct light plants thrive on direct light from the sun. This light comes through south and west facing windows.  Croton, String of Pearls, Jasmine, Geraniums, Cactus, Hibiscus, Jade Plant, Papyrus, Aloe Vera, Herbs, Succulents
Bright light is the sweet spot between medium light and direct light, seen beside a south or south-west facing window   Umbrella Plant, Fiddle Leaf Fig, Bromeliads, Rubber Tree, English Ivy, Sago Palm, African Milk Bush
Medium/Partially shaded plants will receive either a few hours of morning or afternoon sun, a good few feet from an east window to not receive direct sunlight.  Corn Plant, ZZ Plant, Devil’s Ivy, Chinese Evergreen
Low light plants require little to no direct light. These are classified by being 7ft from a window or receiving no natural light.  Spider Plant, Calathea Rattlesnake, Birds Nest Fern, Nerve Plant
Indirect sunlight passes through a medium of some sort, like a window shade or reflection off of another surface.  Zanzibar Gem, Peperomia Obtusfolia, Modern Bamboo

The labels help you know exactly what each houseplant needs for light. Be sure to check our Beginner Friendly Plants article for our guide to the pros and cons of some of these plants. 

N.E.W.S. — Window placement affects your plant’s access to light

Remember that old acronym to help you remember directions, “NEWS?” The direction your house faces (North, East, West, or South) will affect the amount of light coming into your home.

Window Direction Light Received
North  Minimal, steady, gentle light – not too harsh or too muted.
East Direct sunlight in the mornings, indirect in the afternoon.
West Direct sunlight in the afternoon, indirect in the morning
South Consistent, direct light with long sun exposure. 

Seasonal Changes

Changing of the seasons is an exciting and magical thing to witness. Winter, Spring, Summer, or Fall bring with them shifts in both temperature and light. While you do have control over the temperature of the interior of your home, natural light is an uncontrollable factor, as the intensity and longevity of light will depend on the weather outside. 

Fall and Winter

As the days shorten in the fall and winter months, so does a plant’s opportunity for sunlight. For the ones that love the sun, move them to a brighter spot in your home. Artificial lighting is always an option if compensation of natural light is needed. Be careful of possible drafts and the inevitable dry, chilly winter air that can seep into the home. Plants need to be fed on a regular basis but watering frequency may need to be reduced. With Good Dirt Plant Food, you can continue to feed your plants during the slow growing months. Your plants may be growing at a slower pace but they are alive and active. The plant efficiently stores Good Dirt Plant Food and uses only what it needs. Because our all-natural Plant Food is not salt based and started from seed, it will never harm your plants.

Spring and Summer

Warmer temperatures call for more watering, as plants grow more during these months. The sunlight pouring in will be hotter and harsher than in the colder months, so keep a check on your plant to make sure it doesn’t get scorched unintentionally. Limit the amount of direct sunlight it receives or move it to a shadier area of the home or further away from the window.

In all, light plays a significant role in the life of your houseplants, whether you have only one to nurture or a full-blown jungle. A tip for finding the ideal spots in your home, after taking into account where the optimal spots may possibly be, is to simply move them around using trial and error. If you live in a climate where you can take your plants outdoors with the appropriate lighting, your plants will thank you for the fresh air!

Back to blog

Best Sellers