Crop profile

Broccoli crop profile

A compact-heading brassica, best transplanted as healthy plants and tended until the head forms.

Italiano

Starting method

Transplanting

Direct soil

4 °C

Transplant soil

4 °C

Night minimum

2 °C

Frost buffer

-14 days

Heat stop

28 °C

Harvest

60–80 days

Indoor lead

42 days

Key temperatures

0
5
10
15
20
25
30
35
40 °C

Below 4 °CCold risk: slower growth or cold damage.
4 °CMinimum range to start: direct sowing from 4 °C, transplanting from 4 °C.
4–23 °CBest range for growth and production.
23–28 °CPerformance drops and plants move into stress.
Above 28 °CPause transplants: heat stress risk.

Broccoli cycle

1. Start indoors
Average time:
42 days
2. Transplanting
Soil: at least 4 °C
Night minimum: at least 2 °C
3. Growth
Ideal temperatures 4–23 °C
Avoid peaks above 28 °C
4. Harvest
First harvest around:
60–80 days after transplanting

How to start

Recommended method: transplanting.
Prepare seedlings with mild, steady temperatures.
Transplant when soil has reached at least 4 °C and nights stay above 2 °C.

Temperatures to respect

Direct-sowing soil: minimum 4 °C.
Transplant soil: minimum 4 °C.
Night minimum: minimum 2 °C.
Heat stop: 28 °C.
Suggested frost buffer: -14 days.

Harvest timing

Cycle from transplant to first harvest: about 60–80 days.
Harvest gradually as produce reaches maturity.

Seasonal notes

Protect young plants from late frosts and thermal swings.
In summer, avoid water stress and heat peaks above 28 °C.
Steady growth improves development and harvest quality.

FAQ and sources

When should you transplant broccoli?

Broccoli is mostly grown from transplants. It can start in cool soil, around 4 °C, with nights above 2 °C, and it tolerates light cold. Start seedlings about 42 days before transplanting. It is a cool-season crop: above 28 °C it tends to stress and form less compact heads. For autumn harvests, start seedlings in summer but protect them from extreme heat during the early stages.

What soil does broccoli need?

Broccoli needs fertile, well-prepared but firm soil with steady moisture. Add mature compost before transplanting and firm the soil gently around the seedling: brassicas suffer if they rock in the wind. Keep enough spacing so the heads can form cleanly and with good airflow. Avoid waterlogging, but never let the soil dry out completely while the head is forming. In rotation, do not grow it after other brassicas to reduce pest and disease pressure.

How many days does broccoli take to harvest?

Broccoli is usually harvested 60-80 days after transplanting, when the head is compact and the buds are still closed. Do not wait for yellow flowers to open: quality drops quickly. Cut the central head with a short length of stem; many varieties then produce small side shoots for later pickings. Harvest in the morning and cool the crop quickly if you are not using it straight away, because broccoli loses freshness fast.

Why does broccoli make small heads?

Small heads often come from stressed seedlings, heat, late transplanting, low fertility, or irregular watering. Broccoli needs steady growth: if it stalls while young, it can form a small, premature head. Protect seedlings from summer heat, water deeply, and keep weeds down. Spacing also matters: plants that are too close limit each other. It is better to grow fewer well-fed plants than many crowded weak ones.

How do you protect broccoli from caterpillars and aphids?

Use insect netting from transplanting, especially in seasons when cabbage white butterflies are active. Check the underside of leaves and the centre of the plant regularly. Aphids often settle on tender growth and between the buds, so early action is easier than cleaning an infested head. Keep plants well spaced and do not overfeed with nitrogen, which produces very soft growth. Rotate brassicas every year to lower pest pressure.