Lesson 3
Light — the silent ingredient
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Most plant problems are misdiagnosed as 'I forgot to water' when really the plant is starving for light. Stems stretch, leaves pale, flowers don't come — these are light symptoms.
A bright north-facing window in summer can be plenty for leafy crops and most flowering houseplants. A south-facing window in winter at high latitudes is still poor light. Measure: can you read a book by the light at noon, with the lamps off? That's a workable light level.
How much light does it want?
- Full sun: tomato, basil, chilli, lavender, rosemary, sunflower, zinnia — 6+ hours direct.
- Partial sun: lettuce, parsley, mint, viola, calendula — 3–5 hours direct or all-day bright.
- Shade-tolerant: chives, kale, spinach, hostas, ferns — 1–3 hours soft sun.
Rotate your pots a quarter turn every week — plants lean towards the light and end up lopsided otherwise.