En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Is Rudbeckia hirta annual, biennial... or what?

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.

Need help with plant identification, visit the plant identification page.
 
rate this answer
1 rating

Wednesday - January 20, 2010

From: Beaumont, TX
Region: Southwest
Topic: Wildflowers
Title: Is Rudbeckia hirta annual, biennial... or what?
Answered by: Jackie OKeefe

QUESTION:

The desciption for Rudbeckia hirta says it is biennial and blooms the second year then further down the page it says it is an annual, which is it? Will I see blooms the first or second year?

ANSWER:

There are several factors which can determine a plant's longevity. Rudbeckia hirta (blackeyed Susan) thrives in a wide range of climates and soils. In the wild, having the adaptability to complete its life cycle in one season ensures survival in some environments, while being able to mature for a year before blooming promotes survival in other situations. Since weather conditions can vary considerably year-to-year, this adaptability is one of the qualities that makes  Rudbeckia hirta (blackeyed Susan) such a wide-ranging plant.

In Texas' warm climate, if your Rudbeckia hirta (blackeyed Susan) plant is sufficiently mature and gets enough rain/water it will almost certainly bloom this season. If it gets enough moisture through the heat of the summer, it will probably live for another year. If the spent flowers drop seeds, seedlings will sprout with the fall rains for a new generation of plants next year.

According to the  USDA's PDF Fact Sheet :

Adaptation and Distribution
Black-eyed Susan is naturalized in most of the states east of Kansas and the bordering areas of Canada. It is adapted throughout the Northeast on soils with a drainage classification range from well-drained to somewhat poorly drained. It will perform acceptably on droughty soils during years with average or above rainfall, but best growth is achieved on sandy, well drained sites. It is winter hardy in areas where low temperatures are between -30 ° and -20 °F.


Rudbeckia hirta

Rudbeckia hirta

 

 

More Wildflowers Questions

Franciscans and bluebonnets
October 05, 2007 - I always thought the bluebonnets were native to Texas. However, I'm reading a book on the Missions of Old Texas and the author states the Franciscan brought into Texas the horse, cow, honey bees ...
view the full question and answer

Reducing Allergens in Yards and Gardens
January 31, 2012 - What are some allergen-free native plants to Central Texas that thrive in the soil and can survive in the weather?
view the full question and answer

When is it safe to mow wildflowers in Castroville, TX?
May 26, 2010 - Hi Mr. Smarty Plants, My yard in Castroville, TX sprouted many wildflowers early in April. By now the Blue Bonnets are seeded and gone. However, I still have a lot of Mexican Blankets. My husba...
view the full question and answer

Plants for a Steep, Sunny Slope in Iowa
April 28, 2013 - I am looking for plants native to Iowa for a steep, sunny slope or groundcover.
view the full question and answer

Plants to prevent erosion in IL
August 02, 2012 - We just got done building a house and have leveled all of the dirt piles. We do have a row of straw bales to help prevent the dirt from washing onto the neighbors property. It is the wrong time of ye...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center