Summer's Swan Song Ironweed (Vernonia)
|Zones||4 - 9|
|Mature Height||36" tall|
|Mature Spread||40" wide|
|Bloom Time||Early to mid fall|
|Shipping Details||No longer available this season. Learn More…|
|Item Package Size||Plant - 5" Deep Pot|
USDA Hardiness Planting Zones
To determine if a plant is sufficiently cold hardy, the USDA created numbered zones indicating winter low temperatures; the lower the zone number the colder the winter.
- If the coldest winter temperature expected in your area is -15°F (zone 5) then any plants rated zones 3-5 will survive the winter temperatures in your area.
- If you live in very warm winter areas (zones 9-11) plants with zones 3-4 ratings are not recommended. The lack of freezing winter temperatures do not provide a time for winter dormancy (rest).