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New York ironweed

Vernonia noveboracensis · Asteraceae

New York ironweed (Vernonia noveboracensis)
Photo: User:SB_Johnny · CC BY-SA · via Wikimedia Commons

New York ironweed (Vernonia noveboracensis) is a perennial herbaceous plant in the Asteraceae family. It is native to North America. USDA records it as hardy in zone 3 and warmer, down to about -33°F.

At a glance

Typeforb-herb USDA
Lifecycleperennial USDA
Native statusnative USDA
Mature height6.6 ft USDA
Lightpart-shade USDA
Water needmedium USDA
Growth ratemoderate USDA
Soil pH4.5–8 USDA
BloomAugust–September USDA
Flower colorPurple USDA
Hardiness zones3 and warmer USDA
Guild layerunderstory Derived
Nursery availabilityRoutinely Available USDA

USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It grows in partial shade. USDA rates it as having moderate water needs. Its drought tolerance is rated medium. It will not tolerate waterlogged soil — USDA rates its anaerobic tolerance as none. It is recorded on soils from pH 4.5 to 8 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 3.

Size and growth

At maturity it reaches about 6.6 ft, making it a plant that will finish above head height. It grows at a moderate rate.

Bloom period

USDA records a bloom period of August through September. Flowers are purple.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is dark green, medium in texture. Its flowers are conspicuous. It carries conspicuous autumn colour. Its active growth period is summer. USDA rates its lifespan as short, so plan on replacing or resowing it rather than treating it as permanent structure.

What the site needs to provide

USDA records it across sites receiving 40 to 60 inches of annual precipitation. It needs at least 140 frost-free days to finish its season. It roots to at least 6 inches. Fertility requirement: medium.

Propagating it

Propagate it from seed and container stock. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a moderate rate. It does not spread vegetatively, so it will stay where you put it.

Resilience and wildlife

Browsing animals find it moderately palatable, so expect deer and rabbits to take an interest. Its fire tolerance is rated none. Its growth form is recorded as multiple stem.

Role in a guild

Understory. In a layered planting this is the layer beneath the canopy, tall enough to hold structure but shaded from above. The layer is derived by a fixed rule from growth habit and mature height.

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Tags

deciduousdrought-tolerantclay-tolerantnative

Related plants

Others in Vernonia

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol VENO, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

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