Zucchini
Also called: كوسا · كوسة · Kousa · Marrow · Courgette
The heaviest yield per square metre in this guide. One plant gives twenty fruit; two is more than any household needs.
The year at a glance
Each month is split in half. The outline marks now.
Stage by stage
Stage 1 of 9
Seed
Days 0–4
Seed
Days 0–4The seed sits in the soil taking up water and swelling. Nothing shows above the surface — everything is happening underground.
Do now
- Water lightly and often so the soil stays damp but never soaked. Letting it dry out between waterings kills the seed before it sprouts.
- Cover the surface with a thin layer of straw or compost to slow evaporation and steady the temperature.
- Label what you sowed and when. You will need the date to work out the harvest.
Watch for
- A hard crust forming on sandy soil after watering, which traps the sprout underneath. Break it gently.
- Ants carrying small seeds away — a very common problem in Qatari gardens.
In Qatar
Sow three seeds per station and keep the strongest. Seed is cheap; a prepared planting hole is not.
Germination
Days 5–9The seed coat splits: a root pushes down and a shoot pushes up. The two seed leaves that appear are not true leaves — they are the seed’s own food store.
Do now
- Keep moisture constant. The first root is very fine and a single dry day can end the seedling.
- Remove any covering as soon as the first sprout shows, or it will stretch thin looking for light.
- Give bright, indirect light. Direct midday sun will scorch a new seedling within hours.
Watch for
- A long, thin, pale stem: the seedling is not getting enough light and will collapse.
- Sudden wilting with a pinched stem at soil level — damping off, caused by overwatering.
In Qatar
Germinates fast in October’s warmth. Do not sow in December — cold soil rots the seed.
Seedling
Days 10–20The first true leaves appear, shaped differently from the seed leaves. The plant is now feeding itself and the roots are branching fast.
Do now
- Thin crowded seedlings and keep the strongest. Crowding gives you many weak plants instead of one good one.
- Start watering less often but more deeply, to drive the roots downwards.
- Harden the seedling off — build up its sun exposure over a week before transplanting.
Watch for
- Yellowing lower leaves: nitrogen shortage, very common in Qatar’s poor sandy soil.
- Small holes or chewed edges, meaning snails or young grasshoppers.
In Qatar
Grows startlingly fast — from sprout to a metre across in four weeks, so give it the space from day one.
Vegetative growth
Days 21–32The trailing stems run fast and tendrils appear. The plant is hunting for something to climb, and training it now decides the shape of the whole crop.
Do now
- Put the trellis up now and train the stems onto it. Getting the vine off the ground cuts disease and pests dramatically.
- Tie the stems with soft, wide strips of cloth rather than thin twine that cuts in.
- Water deeply in the early morning. Evening watering plus high humidity invites fungal disease.
- Check the undersides of leaves weekly for whitefly and aphids.
Watch for
- Stems trailing on hot ground and scorching underneath.
- Lush leaves but no flowers: too much nitrogen. Stop the nitrogen feed.
In Qatar
Those big leaves lose enormous amounts of water in Qatar’s dry air. Midday wilting is normal if it recovers by late afternoon.
Flowering
Days 33–41Male flowers open first, then female ones with a miniature fruit already behind them. Only the female flowers bear, and pollen has to reach them.
Do now
- If nothing is setting, hand-pollinate: pick a male flower and dab it into the centre of a female one in the morning.
- Cut back nitrogen and raise potassium and phosphorus to support fruit set.
- Never let the soil dry out completely between waterings. Drought now makes the flowers drop.
Watch for
- Flowers dropping without setting fruit: above about 35 °C the pollen goes sterile. Get shade over it now.
- No pollinating insects at all — common on enclosed roofs and balconies.
In Qatar
The first flowers are all male. That is normal and not a failure — the female ones follow a week later.
Fruit set
Days 42–48The petals wither and the ovary behind them swells. Small, hard green fruits appear and grow day by day.
Do now
- Make watering perfectly regular. Swinging between dry and drenched causes most fruit cracking and rot.
- Support the fruiting branches before the weight breaks them.
- Add calcium if your irrigation water is brackish, to head off blossom-end rot.
Watch for
- A sunken brown patch at the base of the fruit: calcium shortage from irregular watering or salinity.
- Small fruits yellowing and dropping: the plant is carrying more than it can feed, or it is thirsty.
In Qatar
Pollination to picking size is four days here. Cropping every other day is not advice, it is a requirement.
Ripening
Days 49–53The fruit stops growing and starts changing colour, turning its starch into sugar. Heat speeds this stage up.
Do now
- Ease off the water slightly to concentrate the flavour — but never to the point of wilting.
- Shade exposed fruit with the plant’s own leaves to prevent sunscald.
- Pick as things ripen. Leaving fruit on the plant stops it setting new ones.
Watch for
- White or leathery brown patches on the sun-facing side: sunscald.
- A small hole with rot inside, meaning fruit worm.
In Qatar
There is no ripening — zucchini is eaten very young. Skin your thumbnail can mark is the right sign.
Harvest
Days 54–110The fruit is ready. The plant is at peak production and will keep bearing as long as you keep picking and the weather holds.
Do now
- Pick in the early morning when the fruit is full of water and will keep longest.
- Use scissors rather than pulling by hand, so you do not tear the branch.
- Keep feeding potassium every two weeks to stretch the picking season out.
Watch for
- New fruit coming smaller: the plant is exhausted and needs feeding.
- The seasonal heat rising, which will shut production down within weeks.
In Qatar
Peak is November to January — a fruit every other day from every plant for eight straight weeks.
End of cycle
Days 111–140Production tails off and the leaves yellow. As the heat builds the plant stops setting fruit altogether.
Do now
- Bring in the last of the fruit, even the ones not fully ripe.
- Save seed from the best fruit on the strongest plant if you want to grow it again.
- Pull the plant and compost the healthy remains; bin or burn anything diseased.
- Work compost into the soil now, ready for the next Al-Wasm.
Watch for
- Leaving diseased plants in the ground carries pests over to next season’s crop.
- Bare soil under the sun goes dead. Cover it or sow a green manure.
In Qatar
Powdery mildew usually finishes the plant before the heat does. That is normal after eight weeks of heavy cropping.
- Sun
- Full sun
- 90 cm apart
- Sow 2 cm deep
- Pot from 30 L
- Cucurbitaceae
Shade net from March
Grows well with
Keep away from
- Water
- High
- Salt tolerance
- Medium
- Heat tolerance
- Medium
18 L/week in winter, 35 L in summer
Soil preparation
Wants room and a lot of organic matter. Dig a big hole and fill it with compost — a single plant needs a full square metre.
Pests
Powdery mildew
- Sign
- White coating on the big leaves — practically inevitable late in the season.
- What to do
- Strip affected lower leaves for airflow and spray a milk solution in the morning.
Squash bug
- Sign
- Coppery-brown eggs in rows on the leaf undersides, and sudden stem wilt.
- What to do
- Check the leaf undersides weekly and wipe the eggs off by hand — easier than any spray.
Common problems
Small fruit yellowing and rotting
- Cause
- A female flower that was never pollinated — the commonest zucchini problem in enclosed gardens.
- Fix
- Hand-pollinate each morning: one male flower will serve three female ones.
Huge leaves, few fruit
- Cause
- Too much nitrogen from fresh manure.
- Fix
- Stop the nitrogen and add a potassium feed such as potassium sulphate. Avoid wood ash, which raises the soil’s alkalinity.
Picking
Cut at 15–20 cm every other day. One left to grow becomes a stringy marrow and stops production dead.
Keeping
Five days refrigerated. The flowers themselves are edible and should be cooked the same day.