How Many Sun Hours Does Your Balcony Actually Get?

The only reliable way to find out how much sun your balcony actually gets is to watch it for a few days and write down when direct sunlight hits, because no rule of thumb, compass direction, or plant tag can tell you what a specific balcony in a specific building actually receives. Most vegetable-growing guidance sorts plants by “full sun” (roughly 6 or more hours of direct sun a day), “partial sun or shade” (4 to 6 hours), and “full shade” (under 4 hours). Those categories are useful once you know your own number. Getting to that number takes a week of paying attention, not a guess based on which way the balcony faces.

What “full sun,” “partial sun,” and “shade” actually mean

These categories come from general horticultural guidance, not from this site, and they describe direct sunlight specifically, not daylight in general. A balcony that is bright all day but shaded by an overhang or a neighboring building for most of the direct-sun hours can still read as “partial sun” or lower, even though it never looks dark. The hours also do not have to be continuous: four hours in the morning and two more in the afternoon add up the same as six unbroken hours for most plants.

The one method that actually works

Pick a few days, ideally a normal week rather than an unusually cloudy or unusually clear one, and check the balcony every hour or two from early morning to late afternoon. Note down each time whether direct sunlight is hitting the space where you plan to put pots, not just whether the balcony is bright. Add up the direct-sun hours at the end of the day. Repeat for a few different days, because a single day can be misleading if it was unusually overcast or unusually clear.

This is slower than reading a compass direction off a plant tag, but it is the only way to get an answer that is actually true for your specific balcony rather than a generic guess.

Why a city balcony reads differently from an open garden

Sunlight guidance written for a house with an open yard assumes the sky is mostly unobstructed. A balcony boxed in by other buildings on a dense city block is a different situation: the building next door, its height, and its distance from you decide a large part of your real sun exposure, often more than which compass direction your balcony faces. Two balconies facing the same direction on the same street can get meaningfully different sun if one has a taller building blocking it earlier in the day.

This also shifts across the year. The sun’s angle changes with the seasons, so a balcony that gets good direct light in one season can lose an hour or two of it once the sun sits lower or higher relative to the buildings around it. If your count feels different a few months from now, that is often the reason, not something wrong with the method.

Why tropical intensity changes the math

Sun-hour categories like “full sun” and “partial sun” were largely worked out for temperate-latitude gardening, where the sun sits lower in the sky for more of the year and the light arriving at ground level is less intense per hour. Direct sun in this climate is stronger per hour than the same nominal “hour of direct sun” at a higher latitude. That does not mean the categories stop being useful, but it does mean a balcony that measures out as “partial sun” by the standard method may still be delivering enough light for a crop that guides elsewhere describe as needing full sun. It is worth treating the categories as a starting point, not a strict cutoff, and watching how plants actually respond once they are in.

Two seasonal factors also cut into the raw hour count without changing the clock time: monsoon cloud cover reduces how much of a nominal sunny window is actually direct light rather than diffuse light through cloud, and the general haze common in the dry season can do the same on a smaller scale. Neither is a reason to skip measuring; both are reasons to expect the number to move around the year.

A simple week-long log

Keeping the check simple makes it more likely to actually get done. A basic version looks like this: check the balcony at a handful of fixed times, say 8am, 11am, 2pm, and 5pm, and note only whether direct sunlight, not just daylight, is hitting the spot where pots will sit. At the end of the day, count the checks where the answer was yes and treat each as roughly representing the interval around it. Repeat across a normal week rather than a single day, and the pattern that emerges, consistently high, consistently low, or genuinely mixed, is more useful than any single day’s count.

What to grow if your balcony reads low on hours

A balcony that logs under four hours of direct sun is not necessarily unusable, it is a different growing brief. Leafy crops generally tolerate less direct sun than fruiting vegetables do, so a lower-light balcony is often still workable for the right selection rather than being written off entirely. The crop-by-crop guides on this site note which plants are more forgiving on light as each one is published.

Related reading

• How to start a rooftop or balcony garden in Dhaka
• Getting permission to use a shared rooftop, for readers on a shared roof rather than a private balcony, where the corner you are allotted can change your sun reading entirely
• A high-sun balcony also dries out faster, which is worth planning for alongside sun hours. See watering a roof garden when there is no tap up there

FAQ

How many hours of direct sun does a vegetable garden need?
Most fruiting vegetables are described as needing 6 or more hours of direct sun a day in general horticultural guidance, with 4 to 6 hours counted as partial sun and workable for a narrower range of crops.

Can I just check my balcony once and be done?
One day is a rough read at best, since weather on that specific day can skew it. A few days across a normal week gives a more honest number.

Does the compass direction my balcony faces matter?
It matters less in a dense city block than it does in an open yard, where the building next door often blocks more sun than the compass direction predicts. Measuring directly is more reliable than reasoning from direction alone.

Why does my sun count seem to change across the year?
The sun’s angle relative to the buildings around you shifts with the seasons, and monsoon cloud cover reduces effective direct sunlight even during nominal sunny months. Both are normal and expected.

My balcony only gets a few hours of sun. Is gardening still worth trying?
Yes, for the right crops. Lower light rules out some fruiting vegetables but still supports many leafy crops, which this site’s crop guides note individually.