How to grow sunflowers in the backyard?

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Introduction on how to grow sunflowers in the backyard

bunch of sunflowers in how to grow sunflowers in the backyardIf there’s one plant giving the summer impression, it must be the sunflower. The sunflower is, to me, one of the most beautiful flowers. The plant also has a really bountiful harvest of seeds that can be eaten, used as animal food or just used as the seed for the next bunch of flowers.

I love my sunflowers because they give me a big harvest I can use for my chickens. And the chickens love it. The sunflowers also take in a specific position in the garden so they can give me a smile every time I come in the garden.

what is a sunflower?

The sunflower is an annual plant. Its Latin name is Helianthus Annuus. The plant is a member of the Asteraceae family. The most beautiful feature of the flower is the large flower head. Some of the sunflowers can grow up to 3 meters tall or about 9.8 feet. the head itself can have a diameter of 30 centimeters or 1 foot. There are also other sunflowers that are smaller or have a more red color than the standard yellow color we now know.

Did you know that the sunflower head is, in fact, a bunch of hundreds to thousands of tiny flowers called florets?

Did you know that the sunflower is the state flower of Kansas? People sometimes call Kansas the Sunflower State for that reason.

where to grow sunflowers?

red sunflower in how to grow sunflowers in the backyardSunflowers like the sun, they love it. Never plant sunflowers in a shadow rich space, they won’t thrive.

The plant loves a well-draining soil and has a deep taproot. So, it’s possible to grow sunflowers in containers but they won’t do as well as they are grown in full soil.

the soil should be kept moist and loose.

the ph-value of the soil should be between 6 and 7,5.

Try to amend the soil with fertile compost or aged manure before you plant your sunflowers. Because sunflowers are really heavy feeders.

Some people tend to stake the sunflowers if they don’t have too many as sunflowers can be really tall and get caught by the heavy wind.

Take into account as well that the plants can shade out other plants or flowers due to their height.

When to grow sunflowers?

You can sow the seeds outside in their final spot as soon as the last frost is over in the spring. The seeds can be sown about an inch deep or a bit less. That’s about 2.5 centimeters deep.

It’s also possible to start the seeds indoors. Growing the seeds indoors can start as soon as 3 weeks before the last frost. You can keep the plants indoors until the last frost has passed. And you can plant out the small plants in their final spot at that moment.


taking care of sunflowers?

sunflower in how to grow sunflowers in the backyardTo grow well, sunflowers need full sun. They grow best in fertile, wet, well-drained soil with a lot of mulch. In commercial planting, seeds are planted 45 cm (1.5 ft) apart and 2.5 cm (1 in) deep.

As already mentioned, think of where you plant your sunflowers as they can take away quite some sunshine from other plants.

Try to avoid places with strong winds and keep the plants protected.

transplanting or planting sunflowers

I already mentioned the transplanting time so there isn’t much left to talk about.

Transplanting the plants is as easy as removing the plant from its pot and put it in the soil at the same level. Just be careful with the roots. Try to keep one plant in one pot to avoid stressing the plant too much when touching the roots. If you mess with the roots too much the plant can be stunted for a while and give smaller flowers.

harvesting sunflowers

Harvesting sunflowers is really easy. Wait until the seeds are fully grown and the flower dies back. The plant will slowly let the flower die back while the seeds are maturing inside the flower.

You have to check out when to harvest the seeds. If you cut off the flower heads before the right time and you’ll have a bunch of unripe small seeds in almost empty shells.

red sunflowerWaiting too long will give you drier seeds but isn’t as bad as harvesting too soon.

Don’t wait until the animals start harvesting the seeds as you will lose a big part of your crop. I’ll be honest, I don’t really mind. I love helping the wildlife so they get their fall food just as we do.

There is a limit to letting the wildlife profit from your sunflowers. Just cover the flowers with fine netting if you know that the neighboring birds will help you harvest just a bit too willingly.

diseases and pests in how to grow sunflowers in the backyard

Birds, field mice, and other creatures

Birds and some other mammals can be real pests in the sunflower business. They will eat the harvest until there’s nothing less. This is quite normal because it’s part of their diet.

Downy mildew Plasmopara Halstedi

Plants will have stunted growth. The leaves will show green and yellow-green lesions on the leaves.

The underside of the leaves will eventually show cotton like fungus.

The stem can have black swollen spots and the plant will eventually die.

Treat with a copper fungicide as soon as the disease shows. Also, remove heavily infected plants and burn them.

Powdery mildew or Erysiphe cichoracearum

Powdery mildew will be easy to spot. The leaves will get a white cotton like fungus on the top side of the leaf. Normally this disease won’t have such a big impact that the harvest is in danger. it does show itself in late summer and early fall.

Use a copper-based fungicide to control if you want to stop the spreading of the disease when it first shows up.

Leafspot or Septoria helianthi

This disease can infect the flower leaves but normally the disease won’t affect the harvest of the seeds.

There’s no real natural treatment for this disease. You can cut off the affected leaves if the plant has enough leaves. Always disinfect your tools after treating infected plants.

Verticillium wilt or Sclerotinia sclerotiorum

The disease will show itself with dead areas along the leaf veins. They will have yellow-green margins. There can also be decayed vascular tissue on the stem.

Infected plants must be removed as there is no treatment once the disease shows up.

You can steam the ground or solarize it before your next seeding or planting.


Up until now, I haven’t had many diseases or pests in my sunflowers but as soon as I can make pictures and research some diseases and or pests, I will amend the article on how to grow sunflowers in the backyard.

So this is it for this article on how to grow sunflowers in the backyard, I hope you’ve found it interesting. If so, please share on social media, with friends, and other gardeners.

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Thanks for reading and see you in the next post.

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