Black-eyed Susan.

En un coup d'œil

Care level

Easy

Plant type

Perennial/Biennial/Annual (often grown as annual or short-lived perennial)

Light

Full sun

Indoor light

direct

Water

Every 7 to 14 days

Mature size

1 to 3 feet tall, 1 to 1.5 feet wide

Growth rate

medium

Hardiness

USDA 3 to 9

Bloom time

Summer to fall

Entretien

Water regularly until established, then it's quite drought-tolerant. Deadheading spent flowers can encourage more blooms and prevent self-seeding if desired. It generally thrives with minimal intervention.

Watering

Water when the top inch of soil feels dry, more frequently in hot, dry weather.

Feeding

Generally does not require fertilizer; if needed, use a balanced, slow-release fertilizer once in spring.

Pruning

Deadhead spent flowers to encourage more blooms and prolong the blooming season.

Repotting

If grown in containers, repot every 1-2 years in spring.

Soil

Well-draining soil

Soil pH

Slightly acidic to alkaline (6.0 to 8.0)

Temperature

-29 to 35°C

Humidity

20 to 50%

Drought tolerance

High

Lifespan

Annual or short-lived perennial.

Deer and rabbits

Moderate; deer and rabbits may nibble on it, especially when other food sources are scarce.

Sécurité

People

Not considered toxic to humans, but it's best to avoid ingestion.

Children

No specific choking or handling hazards are noted, but ingestion should be avoided.

Contact allergens

Some individuals may experience skin irritation from the sap or foliage.

Airborne allergens

Pollen may cause mild respiratory irritation in sensitive individuals.

Edibility

This plant is not intended for human consumption.

Comment l'identifier

• Daisy-like flowers
• Yellow ray petals
• Dark brown central cone
• Hairy stems and leaves
• Rough, toothed leaves

Height

0.3 to 0.9m

Spread

0.3 to 0.45m

Leaves

Green, evergreen

Flowers

Yellow, Brown, 5 to 10cm

Fruit

Black, Brown, Late summer to fall

Problèmes courants

• Powdery mildew — A common fungal disease that appears as white, powdery spots on leaves and stems, especially in humid conditions.
• Leaf spot — Fungal or bacterial infections causing spots on leaves, which can lead to premature leaf drop.
• Aphids — Small, pear-shaped insects that feed on plant sap, causing distorted growth and potentially spreading disease.
• Stem gall midges — Tiny flies whose larvae cause galls (swellings) on the stems, weakening the plant.

La cultiver

Propagation

Seed, Division

When to plant

Spring, Fall

Overwintering

As an annual, it will die back with the first hard frost. If grown as a perennial, cut back the dead stems in late winter or early spring before new growth emerges. It may self-seed readily, so allow some spent flower heads to remain if you wish for volunteers the following year.

In containers

Yes, it can grow well in containers, especially dwarf varieties. A pot at least 8-10 inches in diameter is recommended.

Plant Rudbeckia hirta with other prairie natives that enjoy full sun and well-drained soil for a cohesive and low-maintenance garden.

Bonnes associations

• Coneflower — They share similar growing conditions and bloom times, creating a beautiful prairie-like display.
• Blazing Star — Their vertical flower spikes complement the daisy-like form of Rudbeckia hirta, and they attract similar pollinators.
• Aster — Astors provide late-season color and bloom when Rudbeckia hirta may be finishing, extending the pollinator season.
• Little Bluestem — This native grass provides structural contrast and thrives in the same sunny, well-drained conditions.

À éloigner de

• Overly dense shade — Rudbeckia hirta needs full sun to thrive and will become leggy and produce fewer flowers in deep shade.
• Waterlogged soil — Poorly drained soil can lead to root rot and fungal diseases.

Espèces similaires

• Rudbeckia fulgida — Shares a similar appearance but is typically a more reliably perennial plant with slightly different foliage.
• Helianthus annuus (Common Sunflower) — Both have large, daisy-like flowers with dark centers, but sunflowers are generally much taller and have different leaf shapes.
• Coreopsis lanceolata — Both are cheerful yellow wildflowers that attract pollinators, but Coreopsis has more finely divided leaves and typically smaller flowers.

Science

Family

Asteraceae

Genus

Rudbeckia

Order

Asterales

Class

Magnoliopsida

Native range

Eastern and Central North America.

Conservation

Not of conservation concern.

It thrives in open, sunny areas like prairies, meadows, and roadsides, often colonizing disturbed soils.

Value to wildlife

nectar source, larval host plant

Pollinators

bees, butterflies, moths

Uses

Ornamental, Cut flowers, Pollinator gardens

Taxonomie vérifiée avec le GBIF.

Ce qu'on demande souvent

How much sun does Rudbeckia hirta need?

Full sun is ideal for the best flowering, though it can tolerate partial shade.

What kind of soil does it prefer?

It prefers well-drained soil and is adaptable to various soil types, including poor or clay soils.

When does it bloom?

Typically blooms from early summer through fall, with peak flowering in mid-summer.

Is it a perennial or annual?

It's often grown as an annual or short-lived perennial, depending on the climate and variety.

How tall does it get?

Height varies by cultivar, but generally ranges from 1 to 3 feet tall.

D'où vient le nom

The common name 'Black-Eyed Susan' refers to the dark, prominent center of the flower. The scientific name Rudbeckia honors the Swedish botanist Olof Rudbeck, and 'hirta' is Latin for 'hairy'.

Bon à savoir

• The 'hirta' in its scientific name means 'hairy', referring to its fuzzy leaves and stems.
• It's a popular choice for naturalizing meadows and prairie restorations.
• Drought tolerant once established.
• Attracts beneficial insects like ladybugs.