How to grow sunflowers in your garden

Fields of golden blooms may be a sight to see, but you may be wondering how to grow sunflowers at home. After all, what screams "summer" better than the majestic petals of happiness from a sunflower? In beautiful shades of gold and yellow, they are actually easy to grow. Sunflowers usually bloom during summer and autumn, depending on the variety, and take up to 11-18 weeks to flower. Sign us up.

They’re easy to grow from seed and can reach heights of up to 2-3 metres. The tallest sunflower ever recorded was 9 metres tall! Rob Smith, winner of BBC2's The Big Allotment Challenge and columnist for Garden News, says that "bigger-bloomed varieties like 'Giraffe' can be grown as a companion plant" for your veggie patch, specifically amongst the legumes for a special mix of flowers and vines. Peas, beans or sweet peas help "fix the atmospheric nitrogen into the soil", meaning quick (and better) blooms.

If you are looking to brighten up your garden or allotment with this sunny summer flower, then read on for everything you need to know about how to grow sunflowers - your own Van Gogh in your garden. They'll be a sight to see, for sure. Rob adds that bees and insects will be grateful for your new additions, as well as birds who will peck at the ripe seeds later in the year. They're a pollinator-friendly bunch.

You can use sunflowers in floral arrangements, patio displays and more...

How to grow sunflowers in your garden

Sunflower seeds, multi-purpose compost, a seed tray or small pot, plant labels, and a waterproof marker pen are among the essentials when growing sunflowers from seeds, see below...

The best way to grow sunflowers is to find a sunny, sheltered spot in your garden or precious allotment. To make the soil suitable add lots of well-rotted manure or garden compost before planting. Water your sunflowers regularly. You may also need to add a stick to stake them if they’re in an exposed position.

There are different types of sunflowers so choose your variety carefully as some sunflowers will grow up to four metres tall (American Giant), while others can grow a lot smaller, such as ‘Teddy Bear’ (60-90 centimetres) or ‘Big Smile’ (30 centimetres).

How to grow sunflowers

Thanks to Emma Kendell and Geoff Hodge, both writers for Modern Gardens Magazine, who have helped with a guide on how to grow stunning sunflowers for a tasty harvest for all. Don't forget your watering can, trowel and smart secateurs for accurate, professional planting and pruning...

1. Fill shuttle tray pots with compost. They add that "an old wallpaper paste brush is the perfect tool to brush off any excess." After this, poke a 2.5 cm deep hole in the centre of each and drop one seed. Make sure to cover this with compost.

2. Use a watering can "fitted with a fine rose until all the compost is moist." We'd recommend labelling in case you have other seedlings to take care of. For the best care, Geoff and Emma recommend keeping the potted seeds in a warm, well-lit environment, but out of direct sunlight. Remember to water.

3. Seedlings should appear in "10-14 days", says the writers. Before planting at the end of May, stand the pots "outside during daylight hours, for 10 days" to help them get used to being outdoors.

4. Now, dig a hole twice the diameter of the seedling pot and fill it with water. Remove the plastic pot and pop your seedling into the hole in your flower bed; "the top of the compost should be level with the soil".

5. Once level, fill the hole with soil and "press down firmly using your hands." This is where you need a bamboo stick or flower stick. Don't forget to wrap loose twine around the stem to help the sunflower to stay upright early on. Geoff and Emma recommend adding a copper coil to deter slugs.

6. As your precious sunflowers grow, wrap around more twine up the stem of the sunflower to a bamboo cane or longer flower stick for support. Soon, your flowers will bloom into golden petals. Glorious.

7. Once the flowers have faded, Geoff and Emma recommend cutting the heads from stems, allowing them to dry upside down in an airy place. Here, you can get seeds for snacking, birds or to start again.

FAQs

Where do I grow my sunflowers?

Sunflowers need lots of sun and grow best in fertile soil in a sheltered spot.

They are great for planting in containers or pots, but if you’re looking to grow some really tall sunflowers, make sure to plant them in the ground.

When is best to plant sunflowers?

You can sow sunflower seeds from April to May, individually in 10cm pots, or plant in the garden when the weather is guaranteed to be warm such as early June.

What are the growth stages for sunflowers?

Planting the seedling

Germination

The leaf and plant develop

Growing a bud

Flowering

Pollination

Seed development

Harvesting

Here is a chart by She Said Sunflower displaying the stages of growth.

Tips for caring for sunflowers

Annual sunflowers need lots of water. A good idea is to feed them with tomato feed just before flowering. Don’t allow plants to dry out as tall varieties will not find it easy to recover.

Very tall sunflowers may need the support of a garden cane, especially when growing in an exposed position.

Sunflowers are generally easy flowers to tend to, but young seedlings are susceptible to damage from slugs and snails. If you are only growing a couple of sunflowers, be sure you allow them to grow quite tall before planting out. You could also use wildlife-friendly slug pellets or copper tape to discourage them from pestering the sunflower plant. Or, consider propagating seedlings safely in a greenhouse.

Ellen Kinsey was a Senior Health and Wellness Product Writer and has been a part of Bauer Media since 2020. She has left to study Ayurveda in India to expand her knowledge and skills in the health and wellness field, where she plans to continue making journalistic contributions.