Skip to Content

How Late Can You Plant Sunflowers? (Expert Opinions)

Sunflowers are lovely ornamental plants, which feature beautiful round, yellow blooms.

It doesn’t matter the period in which they are planted (be it in late summer or fall); it still produces edible seeds that are annually grown. However, sunflowers are mostly grown during late spring. But how late can you plant sunflowers?

The answer to this depends on where you plant them. For instance, if planted in the garden, the latest you can sow them is mid-August, whereas if you’re planting in a container, late August is the maximum.

What Are Sunflowers?

Derived from the words sun and flower, the sunflower is a portmanteau scientifically called genus helianthus. It comes from the Asteraceae family and comprises almost 70 species of both annual and perennial herbaceous plants. 

Apart from three of its South American species, every other helianthus species of the sunflower are primarily native to North America and Central America. Most are grown as ornamental plants because of their great size, beautiful flower heads, and edible seeds.

See Also: Beautiful Retaining Wall Ideas

Sunflowers were meant to grow yellow flowers that twirl when facing the sun.

For this reason, they are referred to as heliotropes. The flowers it breeds require sunlight at about 6 to 8 hours to stay healthy; hence, their best bloom time is summer.

They also germinate the best if you plant them in gardens and within soil temperatures of around 50 degrees Fahrenheit.

When Is the Perfect Season To Grow Sunflowers?

How Late Can You Plant Sunflowers

Putting into consideration the fact that when grown, sunflowers may take up to 7 to 10 days before sprouting, while also taking up to 55 to 75 days before they start producing flowers. So, the perfect season to plant sunflowers is after the final frost of late spring.

The final frost of late spring is best because it produces a light frost that will not risk damaging the flowers. But, heavy frosts will result in the freezing of your flowers and possibly cause dehydration.

Therefore, you’re advised to grow sunflower seeds between April to July, as the plant bloom mostly between summer and early fall.

How Late Can You Plant Sunflowers?

As earlier discussed, sunflowers are famous and iconic in late summer to early fall bloom. They are undoubtedly gorgeous flowers that can give you the best indoor and outdoor décor you desire.

However, irrespective of the reason you love the sunflower, it is not uncommon to ask such questions as; is it too late to enjoy these gorgeous flowers if you didn’t plant them late summer or early spring?

Then followed by another like; how late can you plant sunflowers, what are their chances of survival if you plant them after July, and can their seeds be grown during the late summer and still survive the fall?

See Also: Succulent Plant Varieties

Whatever the questions here, it is essential to note that the answers depend on where you intend to grow the seeds.

For instance, how late it is planted in the garden is quite different from how late it is planted in a pot or container.

Again, the time factor is also different based on different locations. We have highlighted its different time limits according to the medium of planting as well as its location or zone as follows;

How Late To Plant Sunflowers in the Garden? 

Most planters that fail to plant their sunflowers at the required time tend to wonder if it is possible to plant the seeds in their garden.

Here is the answer to your puzzle; there’s still an opportunity for you to plant them in mid-August if you had failed to plant in July.

However, once it is past mid-august, do not plant again, as you can save it for planting at next year’s planting season. The reason is that the flower takes approximately 2 months before it blooms.

Therefore, if you plant the seeds in late August, the blooms stand a greater risk of being damaged by the early frost in October before its maturity stage.

Read Also: When To Plant Gladiolus Bulbs

How Late To Plant Sunflowers In A Pot?

The best place to grow sunflower seeds in lower quantities is in a flowering pot or container. The reason might be because the planter only wants a few flowers out of them to help in his interior décor for fall.

Meanwhile, planting sunflowers in a pot makes it easier for you to take them indoors during frost season.

Having said this, it is, therefore, possible to plant the sunflower seeds in a pot in late August. However, you should ensure that the pot is big enough to contain seeds that can germinate as tall as 10 feet. And make sure the soil in the pot is very fertile.

You can also water the flowers once in a while and put them in a location where they can get a lot of bright indirect sunlight. They tend to germinate best if you grow them in a garden and at a soil temperature of about 50 degrees Fahrenheit.

How Late To Plant Sunflowers in Different Zones?

The time limit for growing sunflowers varies according to zones and their climatic conditions. Even in the US region, we have varied time limits for different areas across the US. For instance, for tropical and sub-tropical zones free from frost, you can grow the sunflowers the entire year.

In North Louisiana of the US, you can grow sunflowers during mid-August, contrary to South Louisiana, where you can only grow them during the first week of September.

See Also: When To Pick Banana Peppers