How to Grow and Care for Black-Eyed Susan

Dependable and easy-care black-eyed Susans (Rudbeckia hirta) have become a garden staple. Daisy-like rays of bright yellow petals and dark center disks rise over broad ovate green leaves with a rough texture. This wildflower is native to the central United States and can be seen growing in natural areas and along roadsides in the Midwest.

Black-eyed Susans produce an abundance of nectar and pollen and draw the attention of bumblebees, butterflies, and moths. The plant's ability to self-seed makes it a great choice for abundant wildflower gardens. Most black-eyed Susans are perennials and can be planted after the last frost in spring. It will flower in its first summer, although it can take two to three years to reach full height.

Black-eyed Susan Care

Here are the main care requirements for growing black-eyed Susans:

• Plant in full sun in well-draining soil.
• Water well during the first season. After they are established, black-eyed Susans will become drought-resistant.
• Prefers warmer temperatures.
• Does not require a lot of fertilizer.
  

Light

You will get the best flowering from your black-eyed Susans in full sun, but they can handle partial shade.

Soil

Black-eyed Susans are not particular about soil. They do best in soil that is not too rich and is well-drained, with a pH around 6.8.

Water

Keep the plants well-watered during their first season to get them established—an inch per week through rainfall or irrigation is sufficient. Once established, they will be drought-resistant.

Temperature and Humidity

As a tough summer performer, this plant likes warmer temperatures of 60 degrees Fahrenheit and more. It handles both drought and humidity well, but it does need good air circulation to avoid powdery mildew.

Fertilizer

Go easy on the fertilizer. Black-eyed Susans grow even in poor, infertile soil. A side dressing of compost should be all they will need.

Types of Black-Eyed Susan

There is a great deal of variety within the Rudbeckia genus, and most of the 25 species are true workhorses with very few problems. Some varieties of black-eyed Susan include:

• Rudbeckia hirta 'Becky' is a compact dwarf variety
• Rudbeckia hirta 'Maya' resembles a tall marigold
• Rudbeckia hirta 'Cherry Brandy' has red to maroon flowers around dark center cones.
• Rudbeckia fulgida 'Goldsturm' has daisy-like flowers with a brown/black center cone.
• Rudbeckia laciniata'Autumn Sun' is a golden yellow bloom variety that flowers in mid to late summer.
• Rudbeckia hirta 'Prairie Sun' features orange petals with yellow tips and a green center.
• Rudbeckia hirta 'Indian Summer' displays large yellow flowers and reaches 3 to 4 feet tall.
• Rudbeckia hirta 'Toto Rustic' features autumnal hues; there's also golden 'Toto' and pale 'Toto Lemon'; all grow to about 1-foot tall

Pruning

Black-eyed Susans are easy to establish; they naturalize well and require little maintenance other than deadheading. Regular deadheading of the faded flowers keeps the plants in bloom longer. You can let the last flowers of the season remain on the plants to form seed heads that will feed the birds through the winter. You will also get a good deal of self-seeding, which might not be a bad thing.

Black-eyed Susans make great cut flowers. The seed heads hold up well, too, and look attractive in arrangements. Fast-growing black-eyed Susan is easily the most commonly known Rudbeckia, with its daisy-like flowers with large seed heads. It also has scratchy, hairy leaves that are characteristic of its genus (this may not be one of its best features, but it does help keep pests away).

Propagating

Rudbeckia hirta is a relatively short-lived perennial that might not get old enough to form large, dense clumps. But if it does, it can be divided for propagation in early spring, just as new growth appears, or in autumn, when the plant has finished flowering:

1. Lift the entire plant out of the ground with a shovel. Divide it in half or more sections using pruners or a spade.
2. Replant each section in a new location and keep it well-watered until you see new growth in a few weeks.

Since black-eyed Susans easily reseed themselves, you might automatically have new plants in your flower beds next year.

How to Grow Black-Eyed Susan From Seed

To get a head start on the growing season, start black-eyed Susans indoors from seed about 10 weeks before the last expected frost. Here's how to grow from seed in pots:

1. Plant seeds 1/4 inch deep in trays or pots filled with a moistened seed-starting mix. Perennial varieties will germinate best if the seed containers are kept in the refrigerator or a similarly cold place for four weeks after seeding. Afterward, the soil temperature needs to be warm for germination. Seeds should germinate within seven to 21 days.
2. Harden off the seedlings before planting them outside. Make sure all danger of frost has passed before planting outside.

Black-eyed Susans can also be directly seeded in the garden once daytime temperatures remain around 70 degrees. Here's how to directly sow seeds:

1. Scatter the seeds, cover them lightly with soil, and water well. Keep soil moist.
2. Thin seedlings to 6-12 inches apart for dwarf varieties, 18-30 inches apart for larger cultivars.

If you do not wish to start your own seed, seedlings and plants can be purchased and transplanted.

Common Pests & Plant Diseases

Black-eyed Susan is rarely bothered by serious pests and diseases. However, it can still face issues with aphids, spider mites, snails, and slugs. You can hose off the pests with water or apply a gentle insecticide. Tender young growth may get nibbled, but once they mature and leaves become coarse and hairy, black-eyed Susan is deer-resistant.

Septoria or angular leaf spots are two fungal diseases that form black spots on the leaves and stems. Provide good air circulation by leaving ample space between plants, and avoid getting the leaves wet when watering as that can spread the fungi. Removing and throwing infected leaves in the trash instead of composting helps to contain the spread.

How to Get Black-Eyed Susans to Bloom

Bloom Months

Black-eyed Susan typically blooms in the late spring to early summer months, from March to November, reaching a peak bloom in July and August.

What Do Black-Eyed Susan Flowers Look and Smell Like?

Black-eyed Susans are commonly found in the yellow variety, with deep yellow-orange flower petals and a brown center disc. They have a sweet yet spicy scent that some people liken to anise.

How to Encourage More Blooms

Black-eyes Susans need full sun to bloom. If a tree or shrub is casting shade on them, some pruning might be sufficient to let more sunlight in. Some perennial varieties may not bloom until the second year. Another reason why black-eyed Susans won't bloom is too much nitrogen, which results in lush foliage but no flowers. If using a fertilizer at all (the plants often do very well without fertilization), pick one that is high in bloom-boosting phosphorus.

Common Problems with Black-Eyed Susan

Powdery mildew can affect the leaves in hot, humid conditions. Minimize this by planting in full sun, and thinning the plants to allow for good air circulation.

From: thespruce