Balcony Sun Hours Calculator
A south-facing balcony can catch eight hours of direct sun in June and barely two in December — and that single number decides whether your tomatoes ripen or your basil sulks. Enter your address, the way your balcony faces, and a month to see your true sun budget.
Frequently Asked Questions
How accurate are these sun hour numbers?
The calculation models the sun's true path across the sky for your latitude and the chosen month, then counts the hours when the sun sits within your balcony's facing arc. It does not account for nearby buildings, trees, or mountains that may cast shade, so treat the result as the maximum possible direct sun for an unobstructed balcony.
What counts as full sun, partial sun, and shade?
Full sun means six or more hours of direct sunlight per day, ideal for tomatoes, peppers, herbs, and most flowering plants. Partial sun is three to six hours, suited to leafy greens, many herbs, and shade-tolerant flowers. Shade is under three hours, where ferns, hostas, and foliage plants thrive.
Why does my balcony orientation matter so much?
A south-facing balcony catches the sun for most of the day, while a north-facing one may only see direct sun in the early morning or late evening during summer. East balconies get cool morning light, and west balconies get hot afternoon sun. Orientation is the single biggest factor in what you can grow.
Does the month really change my sun hours?
Yes. The sun rises higher and stays up longer in summer, so a balcony that gets two hours in December might get six in June. The sun also rises further north of east in summer, which lets north-facing balconies catch some direct morning and evening light they never see in winter.
My balcony faces the right way but still feels dark — why?
This tool assumes a clear horizon. A taller building across the street, a roof overhang, or a deep recessed balcony can block the sun even when the orientation is favorable. Spend a sunny day noting when light actually hits your space, then compare it to the chart here to estimate how much obstruction costs you.