Sunflower growing

Information sheet

These uplifting flowers are easy to grow with a little knowledge. Pass on a bit of sunshine and brighten up the day!

  • School term: Early Spring, Late Spring, Early Summer, Late Summer
  • Level of experience: No experience needed
  • Subject(s): Science

Sunflowers are known as being “happy” flowers and make the perfect gift to bring joy to someone's day.
The name Sun Flower is a direct translation from the botanical name Helianthus annus. Heli meaning sun and anther meaning flower.
As soon as the flower forms and opens, you can watch it ‘turn’. Growing in this way, following the path of the sun across the sky is called ‘phototropism’ or ‘heliotropism’. In fact, the Italian word for sunflower ‘girasole’ literally means ‘turning sun’.
Learn how to sow the seeds in pots ready for planting out in your garden with our simple ‘Grow a sunflower’ activity.
Once the flower has faded the sunflower head will have lots of seeds in the centre and these are a great source of food for birds, alternatively you can harvest the seeds and grow them again next year.

Seed harvesting

Leave the flower head on the stem for at least 2 weeks. Once the petals have faded, cut the flower heads off and store them in a sunny, warm, dry place for another week. Spread a sheet of newspaper on a flat surface, gently rub the seed head and the seeds will fall away easily.
Collect them in an envelope or paper bag and store in a dry, cool, dark place until spring when they will be ready to sow and grow once more.

Sunflower sowing

If you live in a region that get lots of dry and sunny weather, you can sow sunflower seeds directly in the ground in spring, as soon as the risk of frost has passed.

  • Choose a sunny spot and get the soil ready by digging it over, removing weeds and raking to get a fine soil texture (it bit like crumble topping!)
  • Make 2 centimetre holes, 30 centimetres apart and drop a seed in each. Cover them up and give plenty of water.
  • Watch out for slugs as soon as your seedlings appear!
  • When they reach 30-45 centimetre in height, put a layer of Organic Matter around, but not touching, the stems to a depth of 10cm.
  • Support the stem as it gets taller by tying it to a cane.
  • Keep watering regularly

Top tips!

  • Feed with a balanced fertiliser once a week! *
  • If you prefer many smaller flowers per stem instead of a large single flower, cut off the growing tip when the plant has reached 1 metre tall. This will encourage side shoots and branching stems. Each branch will form a number of smaller flowers.
*Fertilisers contain concentrated sources of plant nutrients. All fertilisers should quote their N:P:K ratio (Nitrogen, phosphorus and potassium) on the product packaging. A ratio of 7:7:7 indicates a balanced fertiliser (Growmore in this example).

Not just a pretty face
Sunflowers don’t just look pretty, you can eat them too! Add petals and young leaves to brighten up salads and seeds can be roasted or eaten raw as a healthy snack. 
Use sunflower petals and seeds in creams to relieve dry and itchy skins. Sunflower oil is a great source of vitamin E and helps to keep skin moist.
More for your money
Each sunflower is made of thousands of tiny flowers. The yellow petals that you see around the ‘head’ are called ray flowers – like the rays of the sun.

Reach for the sky!
The British record for the tallest sunflower stands at just under 8 metres. Its flowers opened up alongside the television aerial on a terraced house in Wigan in 2014. Record holder Richard Hope took over 30 years to develop his own champion sunflower by selecting seeds from his tallest plants each year.
Become a record breaker
We suggest growing ‘Russian Giants’ that belong to the family of giant sunflowers. They are said to grow over 3 metres tall with flower heads amazingly  50 centimetres across.