Guide
Sunlight requirements chart: hours of sun, crop by crop
"Full sun" and "part shade" are defined terms with hour counts behind them, not vibes. Here's what the labels mean and which crops go under each one.
What the four labels mean in hours
| Label | Direct sun per day | Notes |
|---|---|---|
| Full sun | 6+ hours | Fruiting crops prefer 8+ |
| Part sun | 4–6 hours | Some direct sun expected, morning or afternoon |
| Part shade | 2–4 hours | Direct sun ideally in the morning, shelter from hot afternoon sun |
| Full shade | Under 2 hours | Bright reflected light still counts for something; deep shade grows almost nothing edible |
Hours mean direct sun on the leaves, added up across the day — three hours in the morning plus two in late afternoon counts as five. Bright light bounced off glass and light-colored walls, which balconies have a lot of, doesn't count toward the total but does raise the floor of what part-shade crops can do.
The rule behind the chart
Sun requirements track which part of the plant you're asking it to build. Leaves are cheap — plants grown for foliage stay productive on the least light. Roots cost more, so root crops sit in the middle. Fruit and seed are the most expensive tissue a plant makes, which is why everything you harvest as a fruit — tomato, pepper, cucumber, squash — sits in the full-sun row and sulks anywhere else. Less light doesn't usually kill the shade-tolerant crops; it just slows them down, so expect a part-shade lettuce to take longer to fill out than the same variety in sun — the flip side of the ranges in our days-to-maturity chart.
Crop by crop
| Crop | Requirement | Minimum that still produces |
|---|---|---|
| Tomato | Full sun | 6 h; fruit set drops fast below that |
| Pepper, eggplant | Full sun | 6 h |
| Cucumber, zucchini, squash | Full sun | 6 h |
| Beans, peas | Full sun | 4–5 h with reduced yield |
| Potato | Full sun | 5–6 h |
| Carrot, beet, radish, onion | Part sun | 4 h; roots size up slower |
| Kale, Swiss chard | Part sun | 3–4 h |
| Lettuce, spinach, arugula | Part shade tolerant | 2–3 h, or bright open shade |
| Basil, rosemary, thyme, oregano | Full sun | 4–5 h, slower and leggier |
| Mint, parsley, chives, cilantro | Part shade tolerant | 2–3 h |
| Strawberry | Full sun | 4–5 h with smaller, fewer berries |
Measuring what your balcony actually gets
Guessing sun hours from the compass alone misses the two things that dominate a balcony: the overhang above you and the buildings across from you. The reliable method costs nothing — on a clear day, check the spot once an hour and note whether direct sun is landing where the pots will sit, then add up the checkmarks. Do it once in late spring and remember that the total shrinks as the sun drops toward autumn; an overhung south balcony can be sunnier in October than June because the low sun sneaks under the roofline. Rail-mounted boxes usually clear the overhang's shadow and can run a full label category sunnier than the floor a meter away.
North-facing balconies
A north-facing balcony in the northern hemisphere gets little or no direct sun for most of the year, which rules out the full-sun rows above as producing crops. What still works is the bottom of the chart: leaf lettuce, spinach, arugula, chard grown as baby leaves, and the shade-tolerant herbs — mint, parsley, chives, cilantro. Two things work in your favor: balconies are bright even without direct sun, and shade keeps cool-season greens from bolting in midsummer, so a north-side lettuce pot often outlasts a south-side one. East-facing balconies (morning sun) sit a full tier higher and handle everything through the part-sun rows.
Shade also changes care: less sun means slower evaporation, so pots in shade need water noticeably less often than the default cadence in our watering schedule guide, and overwatering replaces underwatering as the main risk.