How to Grow and Care for Strawflower

Strawflower is a colorful short-lived plant grown as a perennial in optimal zones or typically as an annual in regions with hot summers. The flower thrives in full and partial sun, well-drained soil, and temperatures ranging from 65 to 70 degrees. Strawflower enjoys blooming from spring until fall. Learn more about caring for the strawflower plant in our complete guide.

Strawflower Care

Here are the most important tips when caring for your strawflower plant:

• Plant strawflowers in full sun to promote the most blooms.
• Use sandy and rocky soil with a mildly acidic to neutral pH instead of rich, heavy soil.
• Feed strawflowers monthly with a balanced flower fertilizer.
• Deadhead strawflowers throughout the season to keep them in bloom.
• Stake strawflower varieties over three feet tall. Newer cultivars bred to be stocky do not need staking.

Annual or Perennial?

The strawflower can behave as a short-lived perennial in zones 8 to 11, returning reliably for two to three years. As an annual, the plant grows best in regions with hot summers, so if you have cool summers try growing the similar-looking calendula instead.

Light

Strawflowers thrive in full sun, although they can tolerate part shade. In the latter case, they won't bloom quite as much. Growing strawflowers in full sun will help prevent weak and floppy stems.

Soil

Sandy and rocky soils with a mildly acidic to neutral pH (5.5 to 6.5) are preferred over rich and heavy soils, but any soil is fine as long as it has excellent drainage. Add mulch to retain soil moisture and keep the soil temperature consistent.

When planting in the garden, dig up the soil to a depth of 10 to 12 inches and blend in three inches of compost.

Water

These drought-tolerant flowers will still bloom brightly after a week of dry weather, but don’t let them wither for an extended period.

Weekly watering will keep the flowers perky and fresh. In the absence of rain, give them about one inch of water a week during the growing season but don't let the roots get overly soggy.

Temperature and Humidity

Strawflowers do best in temperatures of 65 to 70 degrees during the day and 60 degrees at night. Strawflowers are not frost-tolerant, so they grow best in warm weather and prefer low humidity.

Fertilizer

Although not heavy feeders, a monthly application of balanced flower fertilizer will keep your strawflowers blooming steadily.

Strawflower plants growing in containers need more frequent fertilizing than those planted in the garden, about every two weeks. For amounts, follow the instructions on the label.

Types of Strawflower

• 'Bright Bikini': Topping out at one foot tall, this is a good choice for containers or the front of the border.
• 'Monstrosum': Fully double flowers in orange, pink, red, and white are a crafter’s favorite.
• 'Sundaze Blaze': An award-winning Proven Winners' introduction, this 1-foot tall strawflower blooms tomato-orange flowers with gold overtones.
• 'Tom Thumb': In contrast to the standard height of 40 inches, this mix won't surpass 15 inches, making it an ideal companion for a sunny container garden or window box.

Pruning

Strawflowers don't need much pruning but to encourage branching out evenly you can pinch the plants back when they reach about a foot tall. This also promotes more blooms.

How to Grow Strawflower From Seed

Strawflowers grown for specific characteristics and colors are best grown from commercial seeds. Or, you can harvest your own seeds from spent flowers in the winter.

1. Start seeds indoors, about six to eight weeks before the average last frost date in your area.
2. Press seeds lightly into moist soil, but don’t cover them, as lighthastens germination. Seedlings should begin to appear in seven to 10 days.
3. Give the seedlings plenty of light from a window or grow them beneath fluorescent grow lights that remain on for 16 hours daily.
4. Harden-off your transplants for two weeks or so, then transplant them into the garden after night temperatures reach about 60 degrees.
   

Collecting Seeds

Harvest strawflower seedheads before they blow off by clipping them from stems and placing them in a paper bag. Shake the bag to separate seeds or rub flowerheads together. Let the seeds dry on a paper towel for a week, then store them in the refrigerator for the winter.

Potting and Repotting Strawflower

Strawflowers make wonderful additions to container gardens and add color to balconies and porches. Choose containers with drainage and place them in full sun, making sure the plants have plenty of air circulation around their bases.

Transplant a strawflower plant if you prefer. Choose a new container that is one size larger than the previous pot. Fill it with fresh potting mix. Plant the ball at a similar depth as its last container. This lowers the risk of traumatizing the plant.

These plants also make lovely filler plants for mixed containers as long as the others thrive in similar conditions.

Common Pests & Plant Diseases

Strawflowers are generally pest and disease-free, but aster yellows virus can affect the plants. This disease is most problematic in areas with leafhopper infestations, where the insect acts as a vector.

Affected plants will exhibit yellowing of leaves and stunted growth. Once a plant has been infected, it cannot be treated but it is important to remove infected plants promptly to prevent the disease from spreading.

Strawflowers are also prone to downy mildew diseases in cool and wet weather, and can be controlled by fungicide.

How to Get Strawflower to Bloom

The word "straw" does not mean the flower is withered and tan. Strawflower blossoms bring vivid colors to your garden and craft projects alike.

Bloom Months

Strawflower blooms profusely from summer into fall, usually June through October depending on your climate. Strawflower blooms can last several days (even a week or more) before dropping. This is true even when harvested for cut flowers.

What Do Strawflower Blooms Look and Smell Like?

These blooms come in warm colors including yellow, orange, red, and occasionally pink and white. They resemble daisies in form with a ray of petals around a central disk, but unlike daisies, the petals are stiff and papery. They aren’t true petals at all, but modified leaves called bracts.

How to Encourage More Blooms

To encourage more blooms, trim off spent flowers and fertilize regularly. Making sure all the basic care requirements are met, such as full sun and healthy soil, will be all this plant needs to flower consistently.

Common Problems with Strawflower

Strawflower is fairly easy to grow but they can encounter some problems from time to time. Here are a few things to look out for.

Leaves Wilting and Turning Yellow

Wilted, yellowing leaves start at the lower leaves and progress up the plant. Eventually, the stem and roots will turn brown and black. This indicates fungal diseases such as verticillium wilt. Fix this by removing the plant from the infected soil and replacing the area with soil that is not contaminated.

Failure to Bloom

Strawflower is a hardy plant but a failure to bloom means its growing conditions are not optimal. Although the plant tolerates some shade, too much can diminish its blooms. Additionally, strawflowers can become leggy as they reach for light if they are in too much shade.

From: thespruce