How to Plant, Grow, and Care for Sunflowers - Backyard Boss
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How to Plant, Grow, and Care for Sunflowers

Tall, radiant blossoms reaching for the sky can mean only one thing: sunflowers! These giant beauties add wonderful texture, color, and earthen bright touches to the garden, and they provide some much-needed folic acid and happy fiber to your diet when you eat their seeds.

This year is my first time growing sunflowers, and I’m thrilled to share my knowledge with you as you plant your own. They’re a fairly easy-to-care-for plant, stunning, and provide lots of benefits (sunflower seeds a super healthy!). So, let’s dig in.

What You Need for Caring for Sunflowers

red trowel in the dirt
Image credits: congerdesign via Pixabay

Before you start the adventure of growing your sunflowers, there are a few tools you’ll need to have handy.

  • Hand trowel
  • Hand cultivator
  • Compost/organic matter for planting
  • Sunflower seeds or plants
  • Watering can
  • A bucket or large container
  • General garden fungicide, as needed

Tips for Planting Sunflowers

Planting sunflowers isn’t difficult, though there are some things to keep in mind as you do so. 

  1. Look for sunny spots. They live up to their name not just in looks but in their insatiable love of sunlight for 6-8 hours a day. They do best in long, hot summers.
  2. Make sure the soil drains well. They should not be planted in low spots where water pools. It will cause root rot.
  3. Sunflowers prefer soil that isn’t too compact. If the soil where you’re intending to plant is tight and dry, pretreat it with a bit of tilling and adding water for several days before planting.
  4. Work some compost or other organic matter into the soil before planting. They love it and thrive best with this kind of foundation.
  5. Sunflowers aren’t particular about the soil pH, but they thrive in slightly acidic and somewhat alkaline soil in the range of pH 6.0 to 7.5.
  6. Though they need lots of sunlight, sunflowers should also be sheltered from strong winds. Planting them near a fence or building is a great way to do this.
  7. If you only have space for a container garden, some smaller varieties of sunflowers do fine in pots. Find varieties, such as Teddy Bear or Short Stuff.

How to Plant Sunflowers Seedlings

human hand holding sunflower seedling on black background
Image credits: PublicDomainPictures via Pixabay
  1. When you’re ready to plant an existing sunflower plant, dig down about 2 feet deep and 3 feet across to give the long taproots as much space as they need to extend and spread as they adapt to their new environment.
  2. Till the soil in these holes, and mix in compost or other organic material.
  3. Then, after the soil has been replaced, dig a hole about the size of the root ball.
  4. Carefully remove the seedling from the tray and place it into the hole.
  5. If you’re starting with sees in biodegradable pots, plant the entire pot into the soil and cover it.
  6. Cover the root ball gently, then water thoroughly,
  7. Space the plants one to two feet apart to give them plenty of growing space.

How to Plant Sunflower Seeds

Wooden bowl filled with sunflower seeds
Image credits: allybally4b via Pixabay

If you’re keen to plant these beauties from seeds:

  1. Dig a shallow 2-inch deep trench. Place seeds 6 inches apart. Aim for 2-inch depth in sandy soil.
  2. Cover the seeds, and water them.
  3. Water the seeds daily (twice daily in hot climates) until the seeds sprout in 7 to 10 days.
  4. When the first true leaves appear, thin the plants to about 2 feet apart.
  5. To enjoy continuous blossoms throughout the season, sow a new row every 2 to three weeks.

Growing Tips for Sunflowers

Chipmunk sitting on top of sunflower head, eating seeds
Image credits: NatureFriend via Pizabay

As your sunflowers grow and bloom, there are a few things you’ll want to do to aid their growth.

  1. Water the plants regularly during the first 20 days of growth and again after flowering. Make these waterings deep and frequent. Then, peter off the water and only water occasionally, but deeply to encourage deeper root growth.
  2. If you have poor soil, add slow-acting granular fertilizer once a year.
  3. As the seeds ripen, protect your sunflowers from birds, squirrels, and other small critters who have a penchant for these lovely seeds. Adding a polyspun garden fleece is the best way to deter the wildlife while still allowing the flowers to grow. You can also trim the leaves that are closest to the heads to remove easy perches for birds.

How to Care for Sunflowers

Close-up of sunflower head
Image credits: Casey Pilley via Pixabay

Sunflowers are a fairly hardy plant that’s able to take care of themselves in many ways. For example, they don’t typically need fertilizer to produce rich harvests and grow tall. Here are tips to help keep them healthy and thriving.

  • When the plant is small, water around the root zone, 4 inches out from the plant.
  • Add some snail or slug bait around the stems.
  • Use bamboo stakes or similar to support larger species of sunflowers.
  • To encourage deep rooting, water deeply but infrequently after the plant is well established.
  • If you choose to fertilize the plants, do so sparingly, with diluted fertilizer.
  • Avoid adding fertilizer near the plant base. Ideally, find a natural or organic option, since likely you’ll be eating the seeds and wanting to reap the health benefits of them.
  • Sunflowers occasionally become infected with rust, downy or powdery mildew. If this occurs, spray the affected plant with a general garden fungicide.

Recommended Sunflower Varieties to Plant

dried sunflower head
Image credits: Matthias Böckel via Pixabay

There are a lot of different sunflower varieties, ranging from giant sunflowers that reach 14-feet or taller to dwarf sunflowers that stay under a foot in height. Some of the most popular varieties include:

  • Russian Mammoth. This sunflower variety grows to 12 feet and has that iconic color of golden yellow blooms with a brown center.
  • Autumn Beauty. Another giant sunflowers option that grows up to 6 feet and comes in bright blooms of yellow, orange, red, or bronze shades.
  • Velvet Queen. They get up to 7 feet tall and come in a gorgeous, velvety dark red.
  • Teddy Bear. This dwarf variety grows up to 2 feet and comes in soft, fluffy yellow.
  • Lemon Queen. These have pale yellow flowers and grow to 6 feet tall.
  • Sunrich Gold. They grow up to 5 feet tall and come in rich, yellow, and green-yellow flowers.

Harvesting Sunflower Seeds

human hands cupped, holding sunflower seeds
Image credits: Natthapat Aphichayananthanakul via Pixabay

In the middle of each flower, you’ll find the flower head after the petals fall off. It means it’s time to harvest! Harvesting sunflowers is rather simple:

  1. Let the flower dry, either on or off the stem, until the back of the flower head turns brown the seeds get plump.
  2. Cut the head of the flower off the stem, leaving about 6-inches.
  3. Place the flower in a container to catch the sunflower seeds.
  4. Brush your hand over the seed heads to knock the seeds out.
  5. Voila. You’re done!

Growing Your Own Sunflowers

Whether you’re looking to flesh out the garden with some stunning blooms or want to grow some nutrient-rich sunflower seeds to supplement your diet, sunflowers are a beautiful option in sunny climates. Using these simple tips and tricks will make growing them easier and more beneficial.