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How Late Can You Plant Sunflowers? – Things To Consider

Whether planted outside or placed indoors, sunflowers are ever beautiful. Their bright yellow blooms remain a distinct work of nature ever both in late summer and fall. Their edible seeds are another reason they are annually planted.

Sunflower seeds are mostly sown in late spring. Yet, a person who didn’t plant during this period could be worried about how late one can plant sunflowers.

What are the chances of Sunflowers surviving if they are planted after July? Can their seeds be sown in late summer and survive fall?

How Late Can you Plant Sunflowers

Firstly, it is significant to understand the nature of sunflowers. An understanding of their nature can be perceived by the name.

The name “Sunflower” is a portmanteau derived from the words sun and flower. The portmanteau was created for these yellow flowers because they twirl towards the sun when the sunsets. Hence, they are heliotropic.

Usually, these flowers need up to six to eight hours of sunlight to remain healthy. For this reason, they blossom in summer.

Moreover, they sprout better when planted directly in a garden. It is best to sow sunflower seeds when the temperature of the soil has reached a 50oF

When Is The Best Time To Plant Sunflowers?

When sown, sunflowers take as long as seven to ten days to germinate. Also, it takes about fifty-five to seventy-five days before they start to bloom.

Therefore, it is advisable to plant them after the last frost of late spring. A light frost may not cause serious damage to your flowers. On the other hand, heavy frosts could cause your flowers to freeze and become dehydrated.

On that account, it is best to sow their seeds between April to July. Sunflowers bloom mostly in the middle of summer and early fall.

Additionally, if you are planting them for the bloom, you should plant them during the recommended period so the flowers will not be prevented from flourishing by the early frost in fall.

How Late Can You Plant Sunflowers?

The answer to this question depends on where you plan to sow the seeds. The time limit to plant them in the garden is not the same as the time limit to plant in a container.

Also, the time limit varies according to the various locations. Hence, the answers to the question are provided below.

How Late To Plant In The Garden

If you did not plant your yellow flowers between in July, you might be wondering if it is too late to sow the seeds in your garden.

Even though you did not sow the seeds in July, you can still sow them in mid-August.

However, after mid-August, it is best to keep your seeds to plant until the next year. Why? The answer is simple.

As explained earlier, it takes the flowers an average of two months to bloom. If the sunflowers are planted in late August, the blooms run at a risk of being destroyed by the early frost in October before they could mature.

How Late To Plant In A Container

If you don’t plan to plant many sunflower seeds or you merely need a few bloom from them to decorate indoors for fall, you should consider planting them in a flowering pot.

Growing sunflowers in a container makes it possible to take them indoors when it begins to frost. Therefore, you can sow the seeds in a container if you are planting in late August.

However, ensure to plant them in a large flowering pot especially, when the seeds are from a variety as tall as 10 feet. Also, plant in fertile soil.

Wet the flowers occasionally and keep in a space that allows sunlight to penetrate.

How Late To Plant Sunflowers According To Different Zones

The time limit to plant sunflowers depends on the climate peculiar to a region. In frost-free tropical and subtropical regions, sunflowers can be planted all through the year.

Even in the US, there are different time limits for different locations.

For instance, in North Louisiana, sunflowers can be planted in mid-August. Whereas, in South Louisiana, they can be planted in the first week of September.

How To Keep Your Sunflowers Healthy When Planted In Mid-august

1. Sow Healthy Seeds

Since you are planting late already, you don’t want to risk planting unhealthy seeds. Sow each seed within six inches apart from each other and one inch deep into the soil.

Before the seeds begin to germinate, protect them from birds. Also, spread a net over the area planted to prevent birds from picking out the seeds before the flowers sprout.

2. Plant On Fertile Soil

Make sure the soil you sow the seeds on is fertile so that they can germinate quickly. Since you are planting late, you should not take any chances of late germination. If the soil does not have sufficient nutrients, add a slow-release fertilizer to the soil.

However, do not add fertilizer to healthy soil. Doing so can produce excess Nitrogen in the ground, thereby causing the stems to break.

Instead of applying fertilizers to healthy soil, add compost to the soil. Also, plant on soil that absorbs and retains water.

3. Water Occasionally

Although sunflowers can thrive without much water, it is necessary to water the seedlings daily around the roots.

The seedling needs to stay hydrated so they won’t dry off and die before they have a chance to grow. On the other hand, water mature sunflowers only once every week.

Restrain from over wetting the soil because the leaves can turn yellow when the soil is too wet. Also, drenched soil can lead to a fungal infection, which will prevent plants from blooming.

4. Protect From Other Pests

Apart from birds, common sunflower pests are squirrels, deer, slugs, and snails. To grow healthy flowers, protect them from these pests.

You can create an electric barrier to keep away deers and squirrels. Also, diatomaceous earth can be applied to the soil close to the sunflowers to kill slugs and snails that come close to them.

A Summary Of How Late To Plant Sunflowers

To sum up, Sunflowers can be planted as late as mid-August, but after that period, keep the seeds for next year’s planting season.

However, if you have to plant sunflowers that year, you can plant even when it’s late August in a container. That way, they can be planted in late summer and survive fall.

Nevertheless, make sure to take special care of sunflowers planted after July.