The Spruce / Phoebe Cheong
Sunflowers(Helianthus annuus) are treasures of the summertime.
These low-maintenance plants typically begin blooming in midsummer and can persist into early fall.
These annuals are also available in other colors, like red, mahogany, cream, orange and bicolors.
The Spruce / Phoebe Cheong
Sunflowers grow on a hairy, sturdy, upright stem that can reach up to 15 feet.
Some varieties are fairly drought-tolerant.
you’re free to direct sow seeds into the ground about an inch deep.
The Spruce / Phoebe Cheong
Maintain a few feet between each sunflower.
Consider planting in a location where they will be sheltered from strong winds.
Soil
Sunflowers will grow in almost any soil, including poor, dry soil.
The Spruce / Ana Cadena
However, they thrive in well-drained soil that contains a good amount of organic matter.
Allow the top 1 to 2 inches of soil to dry out between waterings.
If your sunflowers are drooping and the soil is dry, thats often a sign they need more water.
Temperature and Humidity
Optimal temperatures for growing sunflowers are between 70 and 78 degrees Fahrenheit.
Still, they tolerate high heat as long as their moisture needs are met.
Sunflowers can handle somewhat chilly but sunny environments.
Fertilizer
Sunflowers appreciate afertilizerhigh in phosphorus and potassium.
If you have rich, loamy soil, you likely will not need to supplement it with fertilizer.
If you have poor soil, apply a slow-release fertilizer starting in the spring.
Growers often have to stake their sunflowers, especially the tall varieties, to keep them growing upright.
The plants can become very top-heavy when in bloom.
Planting sunflowers along a fence is the easiest way to stake them.
Bamboo stakes are also strong enough to keep them upright.
Use care when inserting the stakes so you don’t damage the plant’s roots.
You should cut annual sunflowers to the ground once they show signs of browning and drying.
Propagating Sunflowers
Sunflowers can be propagated bytaking cuttingsand rooting them.
The main benefit of propagating from cuttings is to create genetic uniformity in your garden.
It’s best to take cuttings before the season’s growth has matured.
Still, propagating these annuals with seeds is easier.
Cover the seed heads with cheesecloth or a paper bag to catch loose seeds.
When the seeds are completely dry, they can be easily rubbed off the flower head and collected.
Potting and Repotting Sunflowers
Topot a sunflower, select a pot suitable for its size.
Fill the pot or container with loose potting mix and organic matter, and place it in direct sunlight.
Generally, you may use a 7-gallon to 10-gallon pot or plastic container with good drainage.
Since this is an annual plant, there is usually no need to repot it.
Overwintering
Annual sunflowers will succumb to frost so there’s no need to overwinter the plant.
Common Pests & Diseases
Several pests and diseases can affect sunflowers.
Birds and rodents are very fond of the seeds.
Pesticides can help to control the moths.
You may have issues with beetles or caterpillars eating foliage.
Sunflowers can be prone to fungal diseases, includingpowdery mildewand rust.
To avoid such conditions, provide adequate air circulation around your plants and apply a preventive garden fungicide.
it’s possible for you to encourage blooming by giving your sunflower ample full sun and watering regularly.
Handle the flowers very gently while they bloom.
This discoloration, called stem canker, can kill the plant quickly if unaddressed.
Leaf Spot
Sunflower leaves will sometimes display black or brown spots called leaf spot.
Affected leaves will develop spots and then drop from the plant.
No, traditional sunflowers (H. annuus) are annuals and will not return the following the year.
The need to be grown from seed each spring.
Single stem sunflowers bloom one time, while branching sunflowers continue to bloom over a couple of months.
Sunflowers usually take somewhere between 70 and 100 days to bloom from the time the seeds are planted.
Expect at least a couple of months before blooms.
Keep the sunflower head on the stem until it begins to droop and the petals start to fall off.
Then you’re able to harvest the seeds.
Continue to water the plants so they can direct energy toward producing more blooms.
