How long do sunflowers take to grow? Gardening experts reveal when you can expect their sunny blooms to appear

 A sunflower plant.
A sunflower plant.

Sunflowers are the epitome of summer - bright and with blooms reminiscent of the sun itself blooming throughout the month of August. So if you’ve decided to plant some of these beautiful flowers in your garden, you might be wondering how long sunflowers take to grow.

Since we’re now in the time of year when planting sunflower seeds is recommended, it’s helpful to know how long you’ll have to wait for their sunny blooms to manifest themselves. That’s more than likely the reason you’ve planted them, after all.

And while the specific time varies depending on your chosen sunflower variety and other growing conditions, there is certainly a time frame that gardening pros all agree on so at least you have a ballpark to work with.

A sunflower growing in a field
A sunflower growing in a field

How long do sunflowers take to grow?

Unless you already have a sunflower plant or have been given a cutting and know how to propagate sunflowers, it’s likely that you’re growing your sunflowers from seeds. In fact, even if you propagate your sunflowers, you can do so from the established plant’s seeds. And in that case, the time window of growth you’re looking at is between 80 and 120 days.

‘80 to 120 days is a rough estimate for how long it'll take sunflowers to grow from being planted to blooming,’ says Steve Chilton, garden expert at LeisureBench. ‘Of course, it all depends on their growing conditions, as well as the variety of sunflowers.’

Fiona Jenkins, gardening expert at MyJobQuote.co.uk, helps to translate the days into weeks. ‘Sunflowers take between one and three weeks to germinate but once they get going, they tend to grow fast.'

'However, the total time from seed to flowering does vary between 11 and 18 weeks, depending on the variety,' Fiona continues. 'Planting your sunflowers in a sunny but sheltered spot with nutrient-rich soil helps them to grow fast.’

A vase of flowers including sunflowers on a dining table
A vase of flowers including sunflowers on a dining table

Where to buy sunflower seeds

A sunflower plant
A sunflower plant

FAQs

What is the best month to plant sunflowers?

Since sunflowers bloom in the summer, it’s best to plant them in the spring so that they have enough time to grow, similarly to when you'd plant wildflower seeds.

‘Sunflower seeds are best planted between March and May, so they have time to grow before flowering in the summer. If you’re planting seeds straight into the ground, late spring to early summer is best as the ground temperatures are warmer. So, any time between late May and early June is fine,’ Fiona recommends.

Then you can look forward to seeing their beautiful blooms anytime between July and September.

‘Sunflowers typically bloom in the summer and into autumn for around eight to 12 weeks, especially if you re-sow the seeds every few weeks,’ suggests Petar Ivanov, gardening expert and plant expert at Fantastic Gadeners. ‘This way you’ll be able to have blooming sunflowers until the first frost arrives. Some sunflowers can even bloom as early as the month of July.’

A sunflower plant
A sunflower plant

What are the five stages of a sunflower?

In order to understand how long it takes for a sunflower to grow and why, it’s helpful to be familiar with the stages of the flower’s growth.

‘The key growth stages of sunflowers are germination, where the flowers emerge and need damp soil to germinate; vegetation, or vegetative phase, where they develop the aerial part of their taproot and need a large amount of nutrients,' Petar explains.

'Then there's flower bud development, where the leaf and the root system grow almost at their maximum size, they grow high and are sensitive to water and nitrogen deficiency.'

'After that we have the flowering, where each plant flowers and the plants are very sensitive to water stress, which can impact the harvest,' continues Petar. 'And, finally, the maturing of the plant, which is the seed-filling phase and they actively synthesise fatty acids.’

Fiona adds, ‘The final stage is where the flower starts to die off and the head produces seeds – ready for the cycle to begin again.’

Happy sunflower growing!