In the office today we were reminiscing about the great plants we grew in school. How much we loved to watch something that starts at the size of a finger nail grow into something as tall as a giant and as bright as the sun.

Sunflowers are an easy fun flower to grow, especially for kids. They can grow huge with the tallest sunflower on record achieving 8.23 m (27 feet). They can vary in colour, not only are they yellow they can be orange and even red.

Yellow and red sunflowers in fields

Getting Started

The best time to plant the seeds in temperate Australian regions, is anywhere between August to January. Choose which type you would like to grow, there are tall ones, short ones, double blooms and different colours. Sunflowers need 6 to 8 hours or sunshine a day so pick a sunny but well drained spot in your garden to plant the seeds. Dig the soil to a depth of 20 - 30 cms and till thoroughly. Mix in organic matter, then rake the area smooth. Remove any rocks and garden debris.

Sunflower seedinling in soil

1. Plant the seeds approx. ½-inch deep.

2. Space plants: 20 - 30 cm apart, read the instructions on the seed packets to confirm seed depth and spacing for the variety you are planting.

3. Cover the seeds with soil, tap them down by hand, and water them thoroughly.

4. Water every other day or daily in very dry areas.

 

 

Reaching for the sky

As your sunflowers grow you may need to support them, using stakes in the ground to keep them upright during wind and rain. The giant varieties will almost certainly need a stake for support when fully grown.

TOP TIP: Recycle panty hose, using them to secure the sunflowers to a stake.

Giant bud of a sunflower and tall plants

Harvesting

TOP TIP: If you want to use the flowers for flower arrangement, cut the main stem early in the morning, before the flower bud fully opens to encourage side blooms.

When the seeds begin to dry and brown and the flower heads begin to droop, the sunflower seeds are ready for harvesting. Cut the flowers with a two-inch stem allowance and hang the heads upside-down until completely dry. Try to choose a dry, well-ventilated place, out of the reach of animals and birds, to hang the flowers.

Uses for the seeds

pile of sunflower seeds

- Save the seeds for next years crop.

- When I was a child my mum would cut the whole flower off and dry it. Once it was dry she would then hang it out in the garden as a bird feeder.

- Eat roasted on their own or in a recipe.

 

 

TOP TIP: For delicious roasted seeds, soak overnight in water and salt. Then drain and place on a baking sheet. Roast in a low-heat oven (between 200°F and 250°F) until slightly browned. Remove the hull (shell) before eating.

Recap

  • Sow the seeds where you want the plants to grow half an inch deep. 
  • Space plants: 20 - 30 cm apart depending on type (check packet)
  • They like to be a sunny position with well-drained soil.
  • Water the seeds regularly
  • Harvest and enjoy.

Happy Growing!

When to Plant*: Anytime from August to January
Where to Plant: Sunny (6-8 hours), well-drained soil
Soil PH: 6.0-7.5 but they are pretty hardy so will cope with most types of soil
Watering: Keep moist but not water logged
Harvest: 10-11 weeks
Compatible: Cucumbers, Melons, Sweetcorn, Squash
Incompatible: Potatoes

*Based on Temperate Australian Climate

Sunflower Facts

  • Tallest sunflower ever record was 8.23 m (27 feet) in Germany.
  • They come in different colours – Yellow, Orange, Red and even striped.
  • The flowers within a sunflower head are clustered in a spiral pattern whereby each floret is oriented towards the next by the golden angle of 137.5°.
  • Sunflowers can be used to extract toxin such as lead, arsenic and uranium from contaminated soil. For example, sunflowers were used to remove toxins from a pond after the Chernobyl disaster and similar projects took place after the Fukushima nuclear disaster.
  • It is a common misconception that flowering sunflower heads track the Sun across the sky during the day. Young flower buds do display movement similar to this behaviour through a process called heliotropism. But a mature flower usually points in a fixed easterly direction.

 

N.B. This article has been written for Australian gardens. If you're reading this from around the world, we do hope you've found it a useful stepping stone for your own further research.