How much sun does a plant really need?

"Full sun" means at least 6–8 hours of direct sun a day. "Partial sun" (or partial shade) means 3–6 hours. Fruiting crops — tomato, eggplant, pepper, cucumber — want full sun; most leafy crops, herbs and roots are content with partial sun.

Qatar changes the rule

In the cool months, full sun is exactly what fruiting crops want. From March the same spot is too much: leaf temperature climbs past what the plant can cool, it shuts its pores and growth stops. From spring, the best spot for almost everything is morning sun with shade from about 1 pm.

Reading your garden

Watch one spot for a full day and note when the sun arrives and leaves. A west-facing wall keeps baking until sunset; a north-facing one may get almost no direct sun in winter. Buildings and boundary walls make the sunny hours very different from one corner to another.

What to do

• Fruiting crops (tomato, pepper, eggplant, cucumber, okra): full sun October to February, shade net from March.
• Leafy crops and herbs (lettuce, spinach, coriander, mint, dill): partial sun, shade net from February.
• Root crops: at least half a day of sun, and they tolerate less than fruiting crops.
• In pots you can follow the shade: move the pot as the season changes.

When there is too little

Tall, pale, leggy plants leaning towards the light, few flowers and small fruit all mean too little sun. Move the plant, or cut back whatever is shading it.