Registrations are now open for the 2019 UQ Sunflower Competition.

Register here

New Competition Format

Using feedback from schools in 2018, we have updated the competition format to provide more flexibility for participation within school schedules.

What has changed?

  • A Rolling Start - Plant any time after you receive your seed pack.
  • Extended Growing Season - Grow sunflowers when it suits your curriculum, remembering that to grow the biggest sunflowers they need plenty of light, heat and water. If a crop fails during the time frame, you can request new seeds.
  • Video Submission of Sunflower Weigh-In - Submit results by 8 October via video submission.
  • New Prize Categories - Prizes will be awarded for the Heaviest Yield and includes state-based categories for Primary, YR 7-10 and YR 11-12.
  • Activity Day at UQ Gatton - Replacing the 'Weigh in Day', a ‘Sunflower Activity Day’ will be held at Gatton Campus on 21 May, where students can experience agricultural science in action.
  • Online experiments - Scientific in-class sunflower experiments will be available on the website and regular videos will provide tips and advice, and answers from our experts to frequently asked questions.
  • Extended Registrations - Registrations open until 28 June (planting after this date will not allow sufficient time to grow flowers by the deadline).

What stays the same?

  • Plants must be grown in a 14L pot as per previous years and roots must not be in contact with soil outside of the pot.

About Sunflower competition

The University of Queensland’s Sunflower Competition is designed to inspire current science students to become the next generation of plant and agricultural scientists and support teachers to deliver their science curriculum in a plant-based context. The competition provides an interactive learning opportunity with school-based experiments and an optional day of workshops and awards at the UQ Gatton campus.

Rules of the Competition

Teachers and students can participate in a number of ways. 

You can

  1. Grow sunflowers at your school as part of the curriculum (with optional attendance at Weigh-in Day)
  2. Bring the sunflowers you have grown to the UQ Gatton campus to compete for prizes at the official Weigh-in Day.
  3. If you cannot attend the Weigh-in Day, enter the ‘Heaviest Yield: Regional’ category of the UQ Sunflower Competition by submitting a video showing the sunflower head being removed and weighed on a set of calibrated digital scales. Video must be in MP4 format, maximum 30 seconds and submitted by 12 noon on the day prior to Weigh-in Day.
  4. Enter the ‘Communicating Science’ or ‘Scientific Investigations’ categories in the Queensland Science Contest by submitting your entry to the UQ Sunflower completion before May 22. Submit before May 8 if you would like your entry displayed at the Weigh-in Day.

Download the rules (pdf 450KB).


You will be provided with a booklet containing several experiments you can complete in your school. These include a few simple ‘beginner’ experiments aimed at grades 7-8 and some suggestions on how to make the existing experiments more ‘advanced’, targeting grade 11-12 students. Each experiment includes contextual information about how the experiment relates to the real world and the concepts covered. 

In addition to growing sunflowers for the competition, you may want to design your own sunflower-based experiment. Sunflowers are a good choice for experiments as they are easy to germinate, grow and maintain.  

Previous weigh-in day photos



Frequently asked questions

What are the important points the judges will look at?

The plant has been grown in a 14 litre pot or smaller, grown in a solid medium (not grown in a hydroponic situation) and in the container presented. The roots have not grown through the base of the pot and were not cut off in order to bring the plant to the competition. The pot is of the correct size. We strongly suggest competitors use only a recommended pot if you are bringing your plants to the competition day.

What part of the plant is included in the weigh-in?

All parts of the plant above the cotyledonary node are included. This includes the flower head, all leaves and stem.

What is the cotyledonary node?

This is the first node produced by the seedling when it germinates. It is the node where the cotyledons are. Cotyledons are the first two leaves to emerge after the sunflower seed germinates. The nodes is an area on the stem where the leaves are attached.

Do sunflowers really face the sun?

In a certain stage of growth known as the “budding” stage, sunflowers do face the sun, however, they will not do so permanently.

What is the best time for growing sunflowers?

Sunflowers can be planted all year round though they thrive best during warm summer conditions.

How many flowers or heads does the sunflower plant have?

The cultivated sunflower should only have one flower or head though other cultivated and wild varieties are known to have multiple flowers.

Why are sunflowers grown as a commercial crop in Australia?

The sunflower is a major summer oilseed crop and consumers are becoming more aware of the benefits of the various types of sunflower oil. Sunflower oil is light in taste and appearance. It is also popular because it is low in saturated fats and high in vitamin E. Sunflower seeds are very nutritious, boasting high levels of zinc, potassium and phosphorus.

Why is my sunflower not growing well?

Many variables contribute to strong sunflower growth. Just remember, sunflower plants will mature anywhere between 60-80 days. In the meantime, have you checked:

  • Where your pot is positioned
  • The pH level of your soil
  • Your soil type
  • Any drainage issues (plants should not be waterlogged)
  • How much you are watering? Too much or too little?
  • Fertiliser type and amount being administered.

My sunflower plant is getting quite tall, how can I support the plant?

You may wish to use a piece of bamboo to stake your plants.

Do any pests like sunflowers?

Yes, keep watch for birds, slugs and snails. Be proactive with plants and diseases. Try to check on your plants every day. If you see something developing, you can treat it right away. And remember: treating for pests does not ruin an experiment.


The University of Queensland, Gatton Campus