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When is sunflower season?
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In the middle of summer, it’s easy to wonder “when is sunflower season?” Who wants to wait any longer than we have to for these gorgeous blooms!?
Sunflower season falls in August-September in most climates. The peak of the flowers blooming usually occurs in late August to early September. Sunflower blooming season generally aligns with back-to-school and with annual fall fairs and events to mark the start of the harvest season. Sunflower seeds are typically harvested later in September.
Read on to learn all about when sunflower season happens each year!
When is sunflower season?
Sunflower season starts each year in late summer and stretches into early fall. Sunflowers typically start blooming in August, with longer-season varieties and later-planted crops blooming into September. Peak sunflower season is late August to early September in many temperate climates.
The peak of sunflower season will depend on when your crop was planted, when the right amount of rainfall occurred, and when the temperatures become favorable for flowering. Sunflowers are very sensitive to temperature changes and tend to flower when nights start to get cooler as fall approaches. The flowers want to get their seeds fully grown before frost kills the plants.
Sunflower festivals and farmer florists
Flower farmers and farmers who host sunflower festivals typically do several successive plantings across different fields to extend the period within which the sunflowers are blooming. They may plant a batch of seeds every week in May and early June so that the fields will be bursting with flowers in late August and early September.
Flower farmers and sunflower festival hosts tend to plant florist sunflower varieties. These cultivars have a single stem that grows to 5′-6′ tall. Each plant produces one flower head. One batch of these sunflower seeds planted simultaneously will have a blooming season that lasts about 2-3 weeks as a group.
Sunflowers grown by home gardeners
Home gardeners do grow florist sunflowers as ornamentals but may also grow branching sunflower varieties, tall-growing varieties, and varieties that you can harvest the seeds from for snacking.
Branching sunflower varieties often grow 15-25 flower heads on a single plant. The flowers usually start blooming in July and can last until frost.
Taller sunflower varieties can grow up to 15′ tall. They usually have one head that blooms for a few weeks before it droops, but there are tall branching varieties available too that keep putting on new flowers into the autumn.
If you’re growing sunflowers for snacking, your plants should produce seed when the flower heads start drooping and the back of the flower head turns yellow-brown. This usually happens in late August through early October. When the flower heads curl back on themselves and the plant turns a yellow shade, it’s time to cut off the heads and set them out to dry in a sheltered location away from critters and fall rains.
Factors affecting the timing of sunflower blooming
The timing of sunflower season typically depends on the location and climate where the sunflowers are being grown. In general, sunflowers are typically planted in the spring and will start to bloom in late summer.
In areas with warm climates, sunflowers can be planted in very early spring and may start blooming as early as June or July. In cooler climates, sunflowers are typically planted in May or early June, and won’t be ready to flower until August or September.
The specific sunflower season can also vary depending on the variety of sunflower being grown. Some varieties of sunflowers will bloom earlier or later in the season than others.
It is a good idea to research the specific variety of sunflower you are growing to get a better idea of when it will be in bloom. The seed packet typically lists the “days-to-bloom” or “days-to-maturity” of the variety so that you can calculate when to expect your plants to bloom. Quick-growing varieties usually grow in 50-60 days, while the taller plants can take 70-95 days to bloom.
Sunflower season in cold climates
In colder climates, sunflower season may start later and end sooner due to the shorter growing season. This is because there may have been a later start in terms of planting (or replanting if the first planting was killed by a hard freeze). It also may get too cold in the fall for the seeds to have time to mature on the plant. Growers with particularly short seasons should choose quick-growing varieties due to their shorter growing window.
Sunflower season in warm climates
In warmer climates, plants may bloom a bit earlier in the year when temperatures are more favorable for flower production. It’s also important in warmer climates to choose a variety that is adapted to your climate and when the sunflower season usually occurs.
In climates where it doesn’t freeze, sunflowers can be grown year-round! Farmers in areas like Africa and Australia can plant sunflower seeds in the fall for wintertime harvest.
Sunflower varieties by bloom time
Here are the number of days between planting the seed outdoors in the soil and the expected start date of the flower blooming:
- Big Smile: 50-60 days
- ProCut Orange: 50-60 days
- Lemon Queen
- Autumn Beauty
- Mammoth
FAQs about sunflower season
When is sunflower season?
Sunflower season typically depends on the location and climate where the sunflowers are being grown. In areas with warm climates, sunflowers may start blooming as early as May and continue blooming until September or October, as long as the variety planted is a branching variety or has been planted all spring successively. In cooler climates, sunflowers may not start blooming until July or August and may only bloom for a few weeks before being killed by the first hard frost in the fall.
Does the sunflower season vary depending on the variety of sunflower being grown?
Yes, the sunflower season can vary depending on the variety of sunflower being grown. Some varieties of sunflowers will bloom earlier or later in the season than others.
Shorter dwarf sunflowers and florist varieties tend to take 50-60 days to mature. Branching types and tall varieties take more like 70-95 days. Gardeners trying to grow a particularly giant plant may be caring for it for over 100 days!
It is a good idea to research the specific variety of sunflower you are growing to get a better idea of when it will be in bloom.
Can sunflowers be grown in all climates?
Sunflowers are widely adaptable and can be grown in a wide range of climates, but they tend to do best in warm, sunny conditions. They are also relatively drought-tolerant, making them a good choice for areas that receive less rainfall.
However, sunflowers can be sensitive to extreme temperatures, so it is important to consider the local climate. While tiny seedlings are relatively frost-hardy, larger sunflower plants are not at all cold hardy and are killed by even short periods of freezing temperatures.
How long do sunflowers bloom for?
The length of time that sunflowers bloom for can vary depending on the variety of sunflower and the climate in which they are grown. Some sunflowers may only bloom for a few weeks, while others may bloom for several months.
In general, sunflower cultivars that form a single head will bloom for 2-3 weeks. This includes many giant varieties and florist sunflowers like the ProCut line. Branching varieties will start to bloom in the summer months and will continue blooming until frost. These types produce about 20 heads per plant over a period of about 2 months.
Can sunflowers be grown indoors?
Yes – but they might not be happy about it. Sunflowers can be grown indoors, but they do require a lot of light and may not grow as well as they would outdoors.
If you do decide to grow sunflowers indoors, it is important to provide them with plenty of artificial light and to keep the soil moist. It is also a good idea to use a high-quality soil mix and to fertilize the plants regularly to ensure they have all the nutrients they need to grow.
Resources
- How to grow sunflowers
- When to plant sunflower seeds
- How deep to plant sunflower seeds
- How long does it take for a sunflower to grow
- When to harvest sunflower seeds
- How to harvest sunflower seeds
- When is sunflower season
- How tall is a sunflower
References
Need more info?
Sunflowers are so easy and fun to grow! It’s worth thinking a bit more about which varieties to choose, plus whether you’d like any specialty types for your yard that you can’t buy at the farmers market.