When is The Best Time To Plant Sunflowers?

Sunflowers are one of the brightest and happiest plants you can put in your yard. They grow quickly, insects like them, and they’re just plain pretty. Here is the right place to find out when to plant sunflowers so they have the best chance of doing well.

The benefits as well as the drawbacks of each of the three planting times for sunflowers are talked about in this piece. There are also step-by-step directions on how to do the job.

When is The Best Time To Plant Sunflowers

Sunflower Planting Times

As a gardener and former cut flower farmer, I’ve grown a lot of different kinds of sunflowers. I’ve learned over the years that knowing when to plant sunflowers can make the difference between a big, great flower show and one that isn’t quite right.

If you put the seeds at the wrong time, they might not grow or they might rot. Did you know that you can plant sunflowers three times a year?

Each one takes place in a different place, requires a different amount of work, and needs various tools and equipment to complete.

Your options for when to plant sunflowers include:

  • Plant sunflower seeds indoors under grow lights in the early spring.
  • In the middle of spring, plant sunflowers outside, right in the yard.
  • Plant seeds outside in plastic milk jugs during the winter. This is called “winter sowing.”

Types Of Sunflowers

There are many shapes and sizes of sunflowers. Here are some of the most famous garden sunflowers:


“Mammoth” is the name of this huge sunflower variety. This plant is an antique that can grow up to 12 feet tall and has huge flowers that are 12 inches wide and full of seeds. With its fast growth, it makes a great fence, screen, or sunshade for kids.

The best way to plant seeds is to put them an inch deep and two feet apart.

Autumn Beauty

Autumn Beauty is a bright flower that looks great in flower fields. The bright flowers have blooms that are 8 inches wide and come in shades of yellow, bronze, and purple.

Autumn Beauty is a great flower for flower designs because it can grow up to 4 feet tall and has many branches. The plant’s flower buds can be eaten and taste great when battered and fried. It is also known as the common sunflower. It’s best to put seeds 18 inches apart and 2 inches deep.

Moulin Rouge

There is something different about Moulin Rouge. The dark red petals have a tiny bit of yellow at the base, which is brought out by the black center. It always blooms and is simple to grow.

The dark buds are only 4 inches wide and only 4 feet tall. Because it doesn’t have pollen, Moulin Rouge makes a great cut flower.

Teddy Bear Sunflower

Teddy Bear has fully double, fluffy flowers that can grow up to 6 inches across. The bright, deep yellow flowers look like big powder puffs when they don’t have the flat core. This dwarf sunflower looks great in hedges and pots.

Plant three to four seeds at a time, ½ inch deep. When the plants are three weeks old, thin them to an inch apart.

How To Plant Sunflower Seeds

It’s quick and easy to plant sunflower seeds. You give these plants the best start possible by taking the time to pick the right spot and prepare the soil.

Choose A Sunny Spot

Almost everyone knows that sunflowers love the sun. These annuals grow quickly, so find a spot with lots of sun. Plan what you’ll put next to or around your sunflowers.

Sunflowers usually get pretty tall and can block the sun from other plants. With only 70 to 100 days of blooming season, plants can be planted in most gardening zones.

Prepare the Soil: It is important that the soil drains well. Add up to 4 inches of compost if your soil is heavy.

Before you plant, use a complete fertilizer to add nutrients to the dirt.

Add the fertilizer and compost to the top 6 inches of your plant bed and mix them together. A pH level of 6.0 to 7.5 is just right for the soil.

A soil test at home can help you figure out what your garden dirt needs.

Time It Right

You have to wait a little while to decide when to plant sunflower seeds. Sow sunflower seeds when the ground is warm in late spring. When the dirt is 70 to 85 degrees F, most sunflower seeds start to grow.

Just before the dirt gets this warm is the best time to plant sunflowers. The temperature of the ground should be between 60 and 70 degrees. This will happen about three weeks after the last frost in most places.

Sunflowers grow faster if you plant them indoors before the season starts. Put the seeds in peat pots around the time of the last frost in the spring. Once the earth is the right temperature, they should be the right size to move.

Plant The Seeds

Planting sunflowers at different depths and distances will give them different results. How to put sunflower seeds and how deep to go depends on the type of sunflower you want to grow.

Usually, you should put sunflower seeds at least half an inch deep. Leave 6 inches between each seed. There should be two to three feet between each row if you put in rows.

In a few weeks, the plants should be cut back to the right size. Sunflower seedlings will grow in 10 to 14 days if the dirt is just the right temperature.

There needs to be room to grow sunflower seeds. Plant three seeds in each 3- to 4-inch clay pot to start sunflowers indoors.

The best drainage will come from planting media that doesn’t have dirt in it. Most seeds germinate inside in 6 to 10 days. When you put seeds every two weeks, you can have flowers all summer long.

You can have beautiful sunflower blooms until the first frost of fall if you put them one after the other.

Give Plenty Of Moisture

Sunflower seeds need a lot of water to sprout because they have a lot of natural oil in them. After planting, give the ground a lot of water. Frequent, light watering will keep the earth moist until the seeds sprout.

If you are starting your plants indoors, put clear plastic wrap over the pots to keep the water in. As soon as the seeds start to grow, take off the plastic.

Thin The Seedlings

Once the sunflower seedlings have their first real leaves, separate them into rows that are as far apart as your variety’s instructions say.

There may only need to be 6 inches of space between small sunflower plants, but up to 3 feet may be needed for big ones. For yard aesthetics, you can put plants closer together, but flowers will be smaller if they are.

There should only be one sunflower sprout per cup when grown indoors. Just pick the sunflower that is the strongest and pinch back the others.

Growing & Caring For Sunflowers

It’s not hard to learn how to grow sunflowers; they almost grow themselves. They also grow very quickly once they start to grow. A few simple growing tips are all you need to take care of sunflowers.


Sunflowers need a lot of water to sprout, but during the growing season, they only need an inch of water per week. It’s easy to water once a week with a watering nozzle until the top 6 inches of dirt are wet.


If you used compost and/or dung to prepare the soil, you shouldn’t need to add any more fertilizer during the growing season. You can work a balanced, slow-acting granular fertilizer into the dirt around your sunflowers if you think your plants could use more food. Sometimes garden stores sell sunflower fertilizers, but a simple fertilizer is all you need.

Remove Weeds

Control Weeds One of the greatest sunflower challenges is weed control. Weeds are in competition with sunflowers for food and water. To get rid of weeds, you should put down a thick layer of mulch unless you want to till, hoe, or pull them by hand.

Spread organic mulch over your sunflower plant up to 4 inches deep. To keep pests and diseases away, leave some bare earth around each sunflower stalk.

Manage Pests And Disease

A lot of pests love sunflower plants, but they usually only do minor harm. Most of the time, pesticides are not needed unless the damage is very bad. Because most sunflowers depend on insects to pollinate them, pesticides should not be used too much during pollination.

Sunflower moths, cutworms, weevils, caterpillars, grasshoppers, wireworms, and the sunflower maggot are some of the pests you might find.

A big risk is getting sick, but it mostly happens to farm crops. Many diseases can’t hurt the new types of sunflowers. When disease strikes, the only thing that can be done is to get rid of and kill the plants that are sick.

There may be sclerotinia rot, downy mildew, rust, and verticillium wilt. Proper plant spacing in dirt that drains well is the best way to keep this from happening.

Once the seeds are ready to be picked, birds can be a problem. Birds can be scared away with scarecrows, owl decoys, and shiny metal pie plates.

To keep birds away from your seed sunflowers, you can also plant types that are high in oil, like Black Peredovik.

Harvesting Sunflower Seeds

Finally, gather sunflower seeds to enjoy as a snack, to plant again, or to give to birds for the winter.

  • The flower should be left to dry on or off the stem until the back of the head turns brown, the leaves turn yellow, the petals fall off, and the seeds look full but not too tight.
  • Cut the plant’s head off about 6 inches below the flower head with sharp scissors or pruners. Put in a jar to catch any seeds that fall out.
  • Place the sunflower head on a clean, flat surface and get a bowl to hold the seeds.
  • To get the seeds off the plant, rub your hand over the area with seeds and pull them off. You can also use a fork. You can also get rid of them by rubbing the sunflower’s head against an old washboard or something similar. To use, just hold the head and rub it across the board like you would wash clothes.
  • Birds can’t get to the flower heads if you cover them with a light fabric (like linen) and a rubber band before you pick the seeds to roast.
  • You can also cut the flower head off early and hang it upside down until the seeds are dry. Hang it inside or somewhere birds and mice can’t get to.
  • Before putting sunflower seeds out to dry for several hours or overnight, make sure they are clean.
  • Keep seeds that you want to plant again in a cool, dry place with a lid until you are ready to plant them.

Why Aren’t My Sunflowers Growing?

It’s not enough to know when to put sunflowers for them to do well. It’s also important to know how to deal with problems that might come up. The list below should help if your sunflowers either don’t sprout or get eaten by something, even though you did everything right.

  • Not sprouting: Buy new, good seeds; don’t put them too early or in soil that is too wet.
  • Cut off very young plants that were just above the ground: Most likely slugs; use slug bait made of biological iron phosphate.
  • Whole leaves go away: deer; every three weeks, spray the leaves with something that keeps them away.
  • Young plants’ tops are eaten off: Rabbits: put a granular pesticide around the plants to keep them away.
  • Seeds are lost before they can grow: Put floating row cover over the planting area until the plants are an inch tall. This will keep birds out.
  • Chipmunks or mice eat the seeds and dig up the area; cover the planting area with a cage made of hardware cloth until the plants grow.


What Is The Best Month To Plant Sunflowers?

Depending on where you live and the weather, the best month to plant sunflowers will vary. You can plant sunflowers in the spring in the northern US as early as April or as late as mid-June. Plant sunflower seeds in the south of the United States in March or April.

Do Sunflowers Grow Back Every Year?

Some sunflowers only grow one year and need to be planted again the next. But these types can easily make new plants, so you might not need to replant yearly sunflowers. Once they are established, perennial sunflower species will grow back every year.

How Late Can I Plant Sunflower Seeds?

This depends on the hardiness zone in your area. Sunflowers can be grown as late as August in places that are very warm. In cold places in the north, you can plant varieties that grow quickly as late as July and still get a crop before the first frost in early fall.

How Much Sun Do Sunflowers Need?

These plants do best when they get full sun. A sunflower only needs six hours of sun, but the more sun it gets, the better it grows. If you put plants too close together, the leaves won’t get enough light. As plants look for more light, this makes them grow too fast and makes the stems weak.

How Fast Do Sunflowers Grow?

Sunflowers grow very fast. A lot of them can grow up to 12 feet in just 3 months. Sunflowers should be fully grown 70 to 100 days after planting if they are grown in the right circumstances.

How Long Do Sunflowers Live?

Annuals are what most sunflowers are. When the first frost comes in the fall, they die back. They sprout in late spring and bloom in the summer. If you want to grow sunflowers that bloom all summer, the best thing to do is to put them every two weeks.

Are Sunflowers Annuals Or Perennials?

Most types of this bright and beautiful flower are annual, which means they won’t grow back the next year. However, if you leave the flower heads on the plants all winter, they may grow from the seeds that fall off. In late summer and early fall, the Maximillian sunflower blooms with small flowers. It can be grown as an annual all the way up to Zone 3.

Can You Grow Sunflowers In A Pot?

Sunflowers of all sizes can be grown in pots and other containers. You can grow dwarf sunflowers in pots without any problems. Dwarf types of sunflowers don’t have a single stalk with one flower on it. Instead, they are bushy and may have more than one bloom per plant.

Sunflower stalks can be up to three feet tall and up to five inches across. Don’t worry about how to take care of sunflowers in pots; this annual plant needs the same amount of water, fertilizer, and sun whether it’s in a yard or a pot.

Why Do My Sunflowers Begin To Face The Ground?

Sunflowers show heliotropism when they are young. In other words, their flower heads move with the sun as it moves across the sky. The tracking typically becomes less noticeable as the stem ages and turns woody.

The flower won’t follow the sun, but the leaves will. When many types of sunflowers are fully grown, they face the ground, which makes them less likely to be damaged by birds.