Light Needs
Mature Height
Mature Spread
Growing Zones
The showy, fluffy-looking flowers of the Iron Butterfly Vernonia will attract butterflies to your yard while providing a burst of color and texture. The Vernonia lettermannii has tall stems with thin, spindly dark green foliage. The stems are branched near the top and on the terminal end of each branch is a star-shaped purple flower with feathery petals. Enjoy the flowers from late summer into fall.
The Iron Butterfly Vernonia has an upright, mounded growth habit and can thrive in dry, rocky soil that is inhospitable to many other plants. This perennial is a good option for challenging environments and forgetful gardeners. Feature this beauty in beds, borders, and mass plantings. The flowers are very welcoming to butterflies, so this plant is a must-have for a butterfly garden. This cultivar is compact, making it a wonderful option for areas with limited space. Iron Butterfly Vernonia is a hardy perennial in USDA zones 4 through 8.
Iron Butterfly Vernonia Care
Vernonia prefers dry conditions, so plant in average, well-drained soil. Let the soil dry out before giving the plant water. Select an area that receives at least 6 hours of sunlight. Give the plant a dose of balanced fertilizer once each spring.
Deadhead the plant to encourage more blooming. Cut the stems back by one-third if the Vernonia becomes leggy. As a herbaceous perennial, trim all growth to a few inches after the first frost.
Iron Butterfly Vernonia Spacing
Iron Butterfly Vernonia is an upright perennial that will grow 30 to 36 inches tall and wide. Plants can be spaced 30 to 36 inches apart to create a full bed or planting.
Iron Butterfly Vernonia Plant Facts
Growing Conditions
- Hardiness ZonesGrowing Zones
- USDA Zones 4 to 8 (perennial); grown as an annual elsewhere (outdoors year-round); grown indoors elsewhere (outdoors year-round); grown in containers elsewhere (grown as a seasonal crop)
- Sun Exposure
- Full Sun (6+ Hours Direct Sun)
- Mature Height
- 3 Feet
- Mature Spread
- 3 Feet
- Growth Habit
- , Upright
- Water Needs
- Average
Flowers & Foliage
- Flower Colors
- , Purple
- Flower Description
- Purple
- Bloom Time
- Late Summer to Early Fall
- Foliage Color
- , Green
- Foliage Description
- Green
- Foliage Type
- , Herbaceous
- Seasonal Interest
- , Summer Flowering, Fall Flowering
Garden Benefits
Plant Overview
- Common Name
- Iron Butterfly Vernonia
- Botanical Name
- VERNONIA 'IRON BUTTERFLY'
Simple Plant Spacing Calculator
Please Note: The pictures below are to give a general representation of the different container sizes. The actual size/ages of plants are estimates and will vary based on type of plant, time of year, last pruning & many other factors.
Also Known As:
Quart
Plant Age:
~ 6 months - 1 year
Plant Size:
~ 4"-8"
Pot Size:
~ 4.75"H x 4.5"W
Volume:
1.50 quarts
Also Known As:
2.5 Quart Pot
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 8"-12"
Pot Size:
~ 6.5"H x 6.5"W
Volume:
2.20-2.30 quarts
Also Known As:
#1 Container
1 Gallon
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 10"-14"
Pot Size:
~ 7"H x 7.75"W
Volume:
2.26-3.73 quarts
Also Known As:
#2 Container
2 Gallon
Plant Age:
~ 1.5 - 3 years old
Plant Size:
~ 12"-18"
Pot Size:
~ 9.5"H x 9.5"W
Volume:
1.19-1.76 gallons
Also Known As:
#3 Container
3 Gallon
Plant Age:
~ 2 - 4 years old
Plant Size:
~ 12"-30"
Pot Size:
~9.5"H x 11"W
Volume:
2.32-2.76 gallons
Also Known As:
#5 Container
5 Gallon
Plant Age:
~3-4 years old
Plant Size:
~ 20" - 60"
Pot Size:
~11" H x 10 1/2” W
Volume:
3.5 - 4 gallons
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Plants that are currently in stock typically ship within 2-7 business days after your order is placed.
Plant Addicts ships to the lower 48 states within the U.S. Unfortunately, we do not currently ship to Alaska, Hawaii, or internationally.
This plant cannot be shipped to the following states: AK, HI. These restrictions apply only to this specific plant due to agricultural regulations or other limitations. Other plants may still be available for shipping to these states.
If you have any questions about shipping restrictions, feel free to reach out to our team!