How to plant

Sunflowers are fun and easy to grow - kids love them, birds adore them and Alan Turing was fascinated by them.

You can plant them in two ways.

Indoors

In early spring, plant seeds in pots so that they aren’t killed off by frost

  • Where: In individual pots of good multi-purpose compost from March to avoid frosts.
  • How: Sow 2 seeds together, push them into the compost and cover with about 1.5cm of compost. Water well. Keep moist.
  • Care: Keep the seeds moist. Seedlings usually appear within 14-21 days. Plant outside when there is no risk of frost (from late May) – when you are ready, stand the pots outside for a few days. Prepare the soil where you intend to plant them (get rid of weeds, add lots of compost and water well), then plant the seedlings. If planting more than one, leave 45cm between each seedling.

Outdoors

In late spring, sow seeds direct into the ground, once the risk of frost has passed

  • Where: In your garden, into soil that is free of weeds (add lots of compost and turn the soil to prepare). You can also plant into large tubs and containers.
  • How: Dig holes around 5cm deep and 45cm apart. Sow two seeds together, covering lightly with around 1.5cm of soil. Firm gently and water well. Seedlings appear after 14-21 days.
  • Care: Remove weaker seedlings, leaving one per position. Seedlings removed can be transplanted 45cm apart.

What to plant

There are lots of different types of sunflowers, but the ones that are best for this experiment are the taller ones, varieties such as Russian Giant, Giant Single and Giant Yellow. These varieties grow to around 8-10 feet high. You can buy seeds from any high street gardening shop, as well as garden centres and large DIY chains. Packets of seeds cost as little as 75p.

Where to plant

Sunflowers, as the name suggests, need sun – and lots of it. They also need a sheltered spot (so that they don’t get blown over when it’s windy) and something close by that they can be tied to once the seed head starts developing (such as a fence, post or sturdy stake).

What next?

All you need to do is now is nurture your plant, keep the seed head and take part in the head count in the autumn. Don’t worry, you’ll get plenty of help to do that, either in person at one of our special counting locations, or you’ll be able to post your ‘spiral counts’ online. Researchers at The University of Manchester will then collate the data, and the results will be announced during Manchester Science Festival. Make sure you register to appear on our growers' map.