Contents
Description
Helianthus Giganteus, also known as giant sunflower or tall sunflower, is a native plant to North America. It belongs to the Asteraceae family and is a biennial or perennial plant, depending on the climate. The plant can grow up to 10 feet tall and produces large yellow flowers with dark centers that bloom in late summer to early fall. The leaves are green and rough-textured, with a lance shape and toothed margins. Helianthus Giganteus is often used for ornamental purposes in gardens and landscapes.
Taxonomic Information
| Domain | Eukarya |
|---|---|
| Kingdom | Plantae |
| Phylum | Spermatophyta |
| Class | Magnoliopsida |
| Order | Asterales |
| Family | Asteraceae |
| Genus | Helianthus |
| Species | Giganteus |
Appearance
Helianthus Giganteus has a thick stem that can grow up to 4 inches in diameter, with rough and hairy texture. The plant produces large yellow flowers with a diameter of up to 10 inches, which bloom in late summer to early fall. The flowers have dark centers, which are actually a collection of tiny flowers called disk florets. The leaves are green and rough-textured, with a lance shape and toothed margins. The plant can grow up to 10 feet tall, making it an impressive addition to any garden or landscape.
Care Guide
Helianthus Giganteus is a low-maintenance plant that can thrive in a variety of conditions. Here are some tips for caring for your giant sunflower:
- Water: Helianthus Giganteus prefers moist, well-drained soil. Water the plant deeply once a week, or more often in hot, dry weather.
- Fertilization: The plant does not require much fertilization, but a light application of a balanced fertilizer in the spring can help promote growth and blooming.
- Soil: Helianthus Giganteus can grow in a variety of soil types, but prefers loamy, well-drained soil. If your soil is clay-heavy, consider adding organic matter to improve drainage.
- Sunlight: The plant prefers full sun, but can tolerate some shade.
- Hardiness Zones: Helianthus Giganteus is hardy in USDA zones 4-9.
Common Pests & Diseases
Helianthus Giganteus is generally resistant to pests and diseases, but can sometimes be affected by the following:
- Aphids: These small insects can cause distorted growth and yellowing leaves. They can be controlled with insecticidal soap or neem oil.
- Slugs and snails: These pests can cause damage to the leaves and flowers. They can be controlled with slug and snail bait.
- Mildew: Powdery mildew can affect the leaves of the plant, causing a white, powdery coating. It can be controlled with fungicides.
Habitat
Helianthus Giganteus is native to North America, and can be found growing in prairies, meadows, and along roadsides. The plant prefers full sun and moist, well-drained soil, but can tolerate a range of growing conditions.
Question and Answer
Q: Can Helianthus Giganteus be grown in containers?
A: While Helianthus Giganteus can technically be grown in containers, it is not recommended due to its large size and deep root system.
Q: How often should I fertilize my Helianthus Giganteus?
A: Helianthus Giganteus does not require much fertilization, but a light application of a balanced fertilizer in the spring can help promote growth and blooming.
Q: Is Helianthus Giganteus deer-resistant?
A: Helianthus Giganteus is not typically deer-resistant, and may need to be protected from deer with fencing or other methods.
Q: Does Helianthus Giganteus attract pollinators?
A: Yes, Helianthus Giganteus is a popular plant for pollinators such as bees and butterflies.
Related Plants
- Helianthus annuus (common sunflower)
- Helianthus maximiliani (Maximilian sunflower)
- Helianthus strumosus (paleleaf woodland sunflower)
References
- “Helianthus giganteus.” Missouri Botanical Garden. Accessed October 28, 2021. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=287017.
- “Helianthus giganteus.” North Carolina State University. Accessed October 28, 2021. https://plants.ces.ncsu.edu/plants/all/helianthus-giganteus/.
