Light conditions for growing houseplants
With today’s wide range of houseplants, it is very easy to choose one and buy it. But making sure it thrives and grows beautifully is another matter. Fortunately, you can count on us to gladly help you choose suitable plants, both in our store and on our website, and for plant lovers who take growing them really seriously, we also have these articles here on our Zelené listy blog.
Today we will focus on one of the most important conditions for a plant’s survival: enough light. Light is what allows a plant to make sugars (energy-rich compounds), which serve as its main fuel. It makes them from carbon dioxide and water, which are simple inorganic substances. A by-product of this conversion is oxygen, which we humans then use. I probably do not need to go into the finer details of photosynthesis here, but every houseplant owner should have at least a basic idea of the topic. That way, your plants will thrive and bring you joy. The very best approach is to find out a plant’s care requirements before you choose it and decide in advance whether it is the right one for you. It does not work that simply, you say? We all know that head-over-heels feeling of falling for a gorgeous houseplant that practically begs us to take it home, right? Yes, yes, you are right, so these are just the theoretical basics, OK? :)
To work out the light conditions in your home, answer the following questions.
- Which direction do your windows face?
To start, try to find out which direction the windows in your rooms face, so you know how intense the light falling on your plants is. Can you see the sun rising from your window in the morning? Then they face east; if, on the other hand, you can see the sunset, they probably face west. Or use a compass to help you, as almost every smartphone has one these days…
North-facing
North-facing windows are generally considered low-light windows that never get direct light. Plants that have similar conditions in their native habitat, growing in the lower layers of rainforests or right on the forest floor, will thrive here. Examples include Philodendron, Epipremnum, Sansevieria, Zamioculcas and Aglaonema.
South-facing
South-facing windows get plenty of light throughout the day, and even intense direct light. Sometimes there can be too much direct light, for example in winter, when the sun is lower in the sky. Keep this in mind when placing plants right on a south-facing windowsill. Direct sunlight could burn the leaves. If needed, at least add a sheer curtain to the window to soften the light. Plants that need a sunny spot will thrive here, such as cacti, aloe vera and all kinds of succulents or peperomias.
East-facing
East-facing windows are probably every houseplant owner’s dream. Almost any plant can handle the amount of direct light that comes through the window in the morning, and during the day there is plenty of indirect light, which really should suit every plant. Right by the window, you can place popular African violets, marantas and begonias, and even shade-loving plants can go farther from the window. Don’t worry, east-facing windows really are ideal for most plants.
West-facing
Light at a west-facing window is more intense, and for many plants these afternoon rays can be scorching. So on the windowsill, place houseplants that do not mind direct light, such as cacti and various succulents. They will have enough light on the windowsill in the morning too. Thanks to their angle, the rays of the setting sun reach farther into the room, so plants that prefer more shade will also thrive here, even as far as 2 meters from a west-facing window. Examples include Sansevieria, Aglaonema and Epipremnum.
- How far from the window?
The distance from the window also tells you how intense the light is. A plant placed right on a windowsill that gets sun all afternoon will have completely different conditions from a plant placed 2 meters from the window that direct sunlight does not reach at any time of day. Keep this in mind when choosing a plant, and find out what it needs.
- Is there anything between the window and the plant?
Will direct sunlight fall on the plant? Or is it standing against the wall next to the window? Do you use curtains, or is there a tall tree right in front of the building? If you are still not sure how much light you have indoors, a smartphone app that measures light intensity, such as Lux Light Meter, can help here too. Depending on how much light they need, plants can then be divided into three main groups: plants for sunny spots, plants for bright spots, and plants that thrive even in partial shade.
Plants for sunny spots
They need light with an intensity of 3,000 to 5,000 lux and do not even mind direct sunlight. Such a spot is right on the windowsill or very close to the window, where nothing blocks the sun’s rays. These plants include cacti, jade plants, aloes, agaves and echeverias.
Plants for bright spots
They need light with an intensity of 3,000 lux or less, but at least about 2,000 lux. Such a spot is near a window, where there is still plenty of light, but without direct midday/afternoon sun. This kind of light is sometimes called filtered light or indirect light. Most houseplants appreciate these light conditions, for example philodendrons, monsteras and Epipremnum.
Plants for partial shade
These plants can make do with an intensity of around 1,000 lux. If a plant is not getting that much light, it also needs less water at each watering. Keep this in mind and check the moisture of the potting mix before each watering, ideally with your finger. Examples include Zamioculcas, peace lilies, various types of ferns and Sansevierias.
Try this test
Choose a spot for your plant. Stand there at high noon. Check whether your body casts a shadow. Is it clearly visible, with straight, sharply defined edges? Then this spot counts as sunny. If the shadow is softer but you can still make out your silhouette without any trouble, you are standing in a bright spot. But if you can barely make out your shadow, you are standing in a spot with partial to full shade. To double-check, you can also open a book and look at a page. Can you read it easily without extra lighting? If not, the spot is most likely too dark for your plants as well.
How can you improve poor light conditions?
Simply washing your windows at regular intervals helps let more light into the room. Even a thin layer of dust on the glass can keep the sun’s rays from lighting the interior well enough. It is also a good idea to remove curtains and blinds, or at least open them during the day. If the room has skylights, your plants will appreciate that too. Skylights are usually well lit all day regardless of which way they face, and they are considered a fifth light source (after north, south, east and west). Light-colored walls and light-colored furnishings also bring more light into a room. In summer, you can move your plants outside to the garden or balcony. It is said that even the darkest outdoor shade is still brighter than the brightest spot behind a window indoors. Outdoors, sunlight falls on plants from all sides, and together with the humidity and air circulation, this makes a summer outdoors a treat for just about any houseplant. Sometimes it also helps to put the plant in a hanging planter, especially in ground-floor apartments, where light falls mainly on the walls and toward the ceiling. For this, you can use, for example, our macramé plant hanger, available HERE in our online store.
Artificial light
There is one more solution that perfectly replaces sunlight, especially in winter, when we all struggle with a lack of light: grow bulbs. These bulbs give the plant the full color spectrum, which it then uses in every stage of its life cycle. These lights can also bring extra benefits for flowering plants, such as African violets, which then hold on to their flowers. In our store, we use SANSI LED Grow bulbs. We have extensive experience with them from our other projects too, and we can truly recommend them. You can now also buy them HERE in our online store.
Here’s to light and houseplants.
Alžběta Lacinová