Someone comes into the shop and asks me what plant would be easy to take care of. It's maybe the most common question I get, and I almost never answer it with a plant. I answer it with more questions: What's the light like where you live? Which way does your window face? How close to it do you actually want this plant to sit?
That back-and-forth is usually where it happens. Somewhere in there, people arrive at it on their own: not all light is the same, and "easy to care for" was never really about the plant. It's about how well the plant and the spot are matched.
So that's what this is: the conversation I'd have with you at the shop about the natural light in your home, written down so you can have it with yourself, in your own place, with the windows you actually have.
The whole thing rests on one idea: light is the ceiling. It sets the most a plant can do, and everything else you'll read about (how you water, whether you fertilize, when you repot) is really just helping a plant reach the ceiling its light already set. That's why "what's your light?" is always my first question, and why it's worth getting good at answering.
I learned to think about it this way from Darryl Cheng of House Plant Journal. I found his work about ten years ago, and it reshaped how I understand light completely. A lot of what follows is me passing you the same launchpad, translated for a rented Hamilton apartment.
You and your plant are measuring different things
Here's what makes light tricky to eyeball: you and your plant aren't measuring the same thing. Your eyes are built to adjust. Walk from a sunny sidewalk into a dim café and within a minute you can read the menu, because your pupils opened up and your brain rebalanced until the room felt normal again. That's a wonderful feature for getting through your day. It just means your sense of bright is relative, always adjusting to whatever room you're standing in.
A plant isn't doing any of that. It doesn't see the room the way you do; it runs on light the way a solar panel runs on sun: photons in, sugar out. So the two of you can stand in the same spot and come to completely different conclusions about it, and the plant's version is the one that decides how it grows.
That's also why "bright indirect light" on the plant tag never quite helped: it's describing the plant's measurement, not yours, and nobody handed you the conversion. It's the same idea we keep coming back to in the fertilizer post: your plant eats light, and fertilizer is a multivitamin, not a meal. Which means the light in a spot isn't a nice-to-have. It's the food supply. The good news is that reading it the plant's way is a skill, not a sixth sense, and the rest of this is how you build it.
It's two questions, not one
Most light confusion clears up the moment you stop asking "is this spot bright?" and start asking two separate questions instead:
- How many hours of direct sun actually land on the plant?
- How strong is the indirect light for the rest of the day?
These are genuinely different things, and a spot can be high in one and low in the other. A north window might get zero direct sun but steady, decent indirect light all day. A blasting west window might get three hard hours of direct sun and then not much else. Once you're tracking both, you can stop guessing. And conveniently, you've got one hand-tool for each.
Tip one: the shadow test (reads intensity)
Hold your hand flat about a foot above the plant, in the spot it actually lives, at the brightest stretch of the day, and look at the shadow it throws:
- A sharp, dark, hard-edged shadow means strong light. That's direct or near-direct sun.
- A soft, fuzzy shadow with blurry edges means medium light. A lot of plants are perfectly happy here.
- Barely a shadow at all means low light. Some plants cope; many just hang on without really growing.
That's the whole test. No app, no purchase, works in any apartment. The shadow reads intensity, which mostly answers question one.
Tip two: how much sky can your plant see? (reads indirect light)
Now get down to the plant's level and look out the window from where it sits, not where you stand. Ask how much open sky is actually in view.
This is Darryl's idea, and it's the one that made everything click for me: a plant's indirect light is basically a function of how much sky it can see. A wide, unobstructed patch of open sky means strong indirect light, even with no direct sun at all. A thin sliver of sky wedged between two buildings, or a view blocked by the balcony above or the big maple out front, means weak indirect light, no matter how bright the room feels to you.
This is the one renters feel hardest. Two apartments can both have "an east-facing window" and behave nothing alike, because one looks out over open space and the other faces the brick wall four feet away. Window direction is only half the story. What the window can see is the other half.
Put the two together and you've answered both questions: the shadow test tells you how strong the beam is, the sky check tells you how much ambient light the spot really gets. That pairing will out-read your eyes every time.
Light gives up faster than you'd guess
Here's the part that catches almost everyone: light falls off a cliff as you move into the room. It isn't a gentle fade. A spot right at the glass can be many times brighter than the same plant shifted a few feet back toward the wall, even though the room looks evenly lit to you (because, again, your eyes are quietly adjusting the whole way in).
A working rule of thumb: for most plants, keep them within about an arm's length of the window. Past that, you're often asking a plant to live on a sliver of the light you think you're giving it.
This one trips up a lot of us, and it makes complete sense why. We place plants where the room wants them: on the far bookshelf, in the bathroom with the tiny frosted window, in the corner that felt like it needed a bit of life. It's a reasonable way to decorate. It's just that the plant was chosen for the room's benefit rather than its own, and from the plant's side that far corner is a lot dimmer than it looks. The happy part is that this is the easiest thing on the whole list to fix, and it costs nothing: move it toward the light.
Reading your windows for natural light: the Hamilton version
Once you can read a spot, here's roughly what each direction gives you at our latitude. (Hamilton sits around 43° north, and in winter that low, short-day sun really changes what each window can offer.)
- South-facing: the brightest you've got, and the longest run of direct sun. In summer it can be strong enough to scorch a thin-leaved plant (more on that in the sunburn post). In our short, low-sun winters, though, a south window turns into prime real estate: from about November to February it's often the only spot getting genuinely strong light.
- East-facing: gentle morning direct sun, then bright indirect the rest of the day. Probably the easiest all-rounder, and forgiving of thinner leaves.
- West-facing: quiet in the morning, then strong, hot afternoon sun. Good light, but that afternoon punch can stress a plant that isn't ready for it.
- North-facing: no direct sun, indirect only. Not a death sentence, just a lower ceiling. Plenty of plants are genuinely content here, as long as you're honest that it's a low-to-medium spot and choose to match.
The catch, and it's a big one for renters: direction is the starting point, not the answer. A south window staring at the building next door can easily underperform an unobstructed north one. Older Hamilton rentals, converted houses, lower-city apartments tucked close together: a lot of us are working with windows that see more brick than sky. That isn't a problem to fix so much as a reality to read, which is exactly what the two tools are for.
One knock-on worth knowing: the more light a spot gets, the faster its soil dries. So as you move a plant somewhere brighter, expect to water a little more often, and let the soil set the timing rather than the calendar (finger in to the first knuckle: dry, water; still damp, give it a day). Light and water travel together. You can't set one and ignore the other.
If you want an actual number
The two hand-tools genuinely carry this whole post, and you never have to spend a cent. But if you like a number to anchor to, light is measured in foot-candles or lux (same idea, different scale), and that's what a light meter or a phone app will show you.
A few honest caveats, so you know what you're actually looking at:
- Your eyes are the least reliable reader, for all the adjusting-in-the-background reasons above.
- A phone app gives you a rough, relative reading. It's estimating from your camera rather than a true light sensor, so don't treat the number as gospel. It's genuinely handy for one thing, though: comparing two spots in your own home against each other ("this shelf reads about double that corner"), which is often all you need.
- A dedicated light meter is the accurate option, because it's built to measure light closer to the way a plant experiences it. Worth it if you catch the bug, completely optional if you don't.
And the honest floor: low, medium, and high are fuzzy, overlapping bands, not real categories. Use them as loose guides, hold them loosely, and let the shadow and the sky do the deciding.
One thing I'm deliberately leaving out here: grow lights. If your space simply doesn't have the natural light for the plants you're dreaming about, that's not a dead end, it's a genuinely good option, and it deserves its own post rather than a rushed paragraph at the bottom of this one. That one's coming.
The greenhouse hangover
Last thing, because it saves a lot of unnecessary panic. Wherever your plant grew up before it reached you, it was almost certainly getting more light than your living room can offer. Ours begin their lives at a nursery, and once they arrive at the shop we keep them under grow lights running 24/7. That's gentler than a greenhouse, but it's also steadier than the light most plants will ever get in a home, where the sun shifts with the season, the weather, and which way your windows face.
So when a new plant drops a couple of leaves, slows down, or looks a little sulky in its first few weeks, that's very often just the plant settling into a dimmer, more variable diet, not a sign you've done something wrong. Give it a beat before you change anything. And I've come to think that in-between step might quietly do them a favour. We hear all the time from folks whose plant is thriving at home, and part of me wonders if some of that comes from the buffer: from the nursery, to a steady stretch under our lights, to your window, rather than one hard jump straight from a growing space into a living room.
It also helps to know that plants take the shape of their light. Stretchy, leggy growth reaching toward the window, smaller new leaves, wider gaps between them: those are usually light signatures, not diseases. Which is exactly why light is the first thing to check when a plant looks off, and why, when we get to the yellow-leaf post, "read the light first" is going to be step one. (Most commonly a yellow leaf is light or water. Sometimes it's just a normal older leaf being retired. Only rarely is it the dramatic stuff.)
Try this tonight
You don't need to overhaul a thing. Pick the one plant that's been looking least happy, and in the brightest part of tomorrow, do three small things:
- Run the shadow test over it.
- Get down to its level and check how much sky it can actually see.
- Notice how far it sits from the glass.
Then choose one move: nudge it closer to the window, try a different window, or decide the spot is what it is and match a lower-light plant to it instead. None of this is permanent. Plants can be moved, light can be worked with, and almost nothing here is a mistake you can't walk back. That's the quiet freedom in learning to read light: once you can see what a spot actually offers, you stop fighting your apartment and start working with it.
And if you'd rather not puzzle it out alone, this is a big part of what our Growing Consultations are for. It isn't only a garden service. Plenty of what I do is standing in someone's living room (or on a video call, if you're elsewhere in Ontario) reading the light window by window, plant by plant, and helping match what you want to grow to what your space can genuinely support. Bring me your trickiest north-facing corner. I love that puzzle.
If you'd like to go deeper on the science and the numbers, House Plant Journal is where I'd send you first. It's the launchpad that got me here, and it's still where I point anyone who wants to really understand the thing.