How To Grow a Sunflower in a Pot

Are you wondering how to grow a sunflower in a pot? It’s easy! It’s a great summer project for front porches, or just to add some bright flowers to your outdoors area.

Summary: How to grow a sunflower in a pot

• Container: Choose a container at least 12 inches in diameter with drainage holes, fill with soil, and place in a sunny location
• Plant the 1-2 seeds ¼ inch deep. Refer to the seed packet’s instructions for your sunflower variety spacing needs. It can be anywhere from 6-18 inches apart.
• Water: Keep the soil damp, but not pooling water until the seedling comes up. 
• Continued Care: Water regularly, especially when they are young and establishing roots. Fertilize your plant every 3-4 weeks with a liquid fertilizer.

For all the details and common questions on how to grow sunflowers a pot keep reading below!

1. Choose the Right Container

• Size: Ensure the container is large enough to accommodate the flower’s root system. A container that’s too small can stunt growth, while one that’s too large will be unnecessary. You will want a pot at least 12 inches in diameter. 
• Material: Containers come in various materials (plastic, ceramic, terracotta, etc.). Plastic holds water better, while terracotta allows for more air circulation. There are also grow bags that are great for storing and affordable, but will not last long. You decide what you like best, because you can use any container.
• Drainage: Your container must have holes at the bottom for excess water to drain. Many plastic pots do not have holes at the bottom, so make sure you make the hole before filling the pot with soil. If your pot doesn’t have drainage holes water will accumulate at the bottom and cause root rot.

2. Preparing You Pot

• You can use garden soil, but it can become compacted in containers. Using a good-quality potting mix that is well-draining will benefit your plants. If I am filling a large pot I will use some dirt from my garden for the bottom half and  potting soil from the top half to save money.  
• I also like to add some worm casting to my soil to give it the extra nutrients that many potting soils are lacking. Worm casting can be found at any big box store by the fertilizers.
• Sunflowers need at least 6 hours of sun. Place your pot in a location that has this amount of sun.

3. Planting your Sunflowers

• When to Plant: Plant sunflower seeds after the last frost in spring when your night temperatures are no lower than 32 degrees. Your last frost date can be found with a simple google search. 
• Direct Sowing:  Plant the seed ¼ inch deep and put 2-3 seeds in each hole. I like to use the back of a sharpie for the perfect hole.  Refer to the seed packet’s instructions for your sunflower variety spacing needs. It can be anywhere from 6-18 inches apart.
• Water: Keep the ground damp, but not pooling water until the seedling comes up.

4. Caring for you Sunflowers

Water

• Plants in containers tend to dry out more quickly than those in the ground. Water regularly but check the soil before watering to avoid overwatering. If you are unsure if you need to water you can stick your finger into the first inch or two of the soil. If it is dry it is time to water. Water until water comes out the bottom of your container
• In the peak heat of the summer you will need to water everyday.

Feed Your Sunflowers THE KEY

• Plants being grown in pots do not have the access to the nutrients in the ground, so you will need to fertilize more often. 
• I add worm castings in the spring when I first plant and then fertilize every 3-4 weeks with a liquid fertilizer.

End of Season Care

Sunflowers are annuals. At the end of the season, you can collect seeds from the flowers to plant the following year. Simply let the flowers dry on the plant, and when the flower heads are completely dead and dry, collect the seeds from the center of the flower and store them in a cool, dry place. FREE SEEDS! Now you know how to grow a sunflower in a pot!

Common Questions

Do sunflowers grow well in pots?

Yes, sunflowers can grow well in pots, but there are some varieties that will do better in pots than others.

How do you keep sunflowers alive in a pot?

Sun, water, fertilize. Simple as that!

How big should a pot be for a sunflower?

At least 12-18 inches in diameter.

How do you take care of a sunflower in a pot?

Sun, water, fertilizer and keep the weeds out.

How do I keep Sunflowers blooming all summer?

Unless you are growing a branching variety of sunflowers the plant will only grow one flower. If you are growing a branching variety keep cutting the flowers! Even if you let some flowers die on the plant, cut them off for the plant to put more energy into growing more flowers and not grow seeds.

How tall do Sunflowers grow?

How tall the Sunflowers can grow will depend on the variety. Usually the front of the seed packet will say how tall the plant can get. Some varieties are bread for cutting and will not grow as tall and some will grow 12 feet tall!

Do Sunflowers come back every year?

No, sunflowers are annuals. You will need to replant every spring.

What temperature will kill sunflowers?

Sunflowers are frost sensitive. When night temps are below 32 degrees they will die.

What month do you plant sunflower seeds?

Plant sunflowers seeds after the last frost in spring when your night temperatures are no lower than 32 degrees. Usually anytime April-July, but check your weather and last frost date to be sure.

Where can I buy sunflower seeds?

Anywhere you can buy seeds you can buy sunflowers, but my favorite places to get unique varieties are

Johnny’s Select Seeds
TrueLeaf market
Botanical Interest
Baker Creek Rare Seeds

Now that you know how to grow a sunflower in a pot I can’t wait for you sunny sunflowers to brighten your summer days. Now you know how to grow your sunflowers, what are the best sunflower varieties of pots? Find the answer HERE.

As always, 

Grow flower to heal your soul,

Beth