En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Friday - August 28, 2009

From: Tucson, AZ
Region: Southwest
Topic: Drought Tolerant, Herbs/Forbs
Title: Range and adaptability of evening primrose from Tucson AZ
Answered by: Barbara Medford

QUESTION:

What is the natural range of the evening primrose? What adaptations does it have to live in the arid Southwest?

ANSWER:

There are 12 plants with the common name "evening primrose" in our Native Plant Database. There are 4 native to Arizona, so we chose to give you the ranges of those. 

Calylophus hartwegii ssp. pubescens (Hartweg's sundrops) -blooms yellow March to August. Range in Arizona from USDA Plant Profile. Range in North America

Calylophus serrulatus (yellow sundrops) - blooms yellow April to July.  Range in Arizona from USDA Plant Profile. Range in North America

Oenothera caespitosa (tufted evening-primrose) - blooms white April to August. Range in Arizona from USDA Plant Profile. Range in North America.

Oenothera speciosa (pinkladies) - blooms white or pink February to July. Range in Arizona from USDA Plant Profile.  Range in North America. 

To try to find out what were the traits of these plants that made them drought resistant, we found three websites that had a great deal of information:  Central Washington Native Plants  Plant Adaptations in Arid Environments; Plant Life in the World's Meditteranean Climates, by Peter R. Dallman, from University of California Press; Arizona Sonora Desert Museum Center for Sonoran Desert Studies How Plants Cope with the Desert Climate.

From this information, we found that the characteristics that the plants share that contribute to their survival are:

Long, narrow leaves, to avoid loss of moisture. Leaves also are hairy or downy, are blue-gray on the underside, and may fold up in the heat of the day.

Most of these plants bloom in the evening, and blooms close the next day when the heat begins to rise, again reducing moisture loss. 

Taproots-the seedlings quickly put down a taproot for moisture, and the mature plant develops a network of fine roots near the surface of the soil.

Plants may go dormant in summer, resprouting with rains.

From our Native Plant Image Gallery


Calylophus hartwegii ssp. pubescens

Calylophus serrulatus

Oenothera caespitosa

Oenothera speciosa

 

 

 

 

 

 

More Drought Tolerant Questions

Tree to replace Betula nigra (River birch) in Memphis
August 13, 2012 - HI Mr. Smarty Pants, I think I need to replace the river birch tree in my west-facing front yard in Memphis, TN. I have sun all day, but it gets really hot in the afternoon. The soil in my yar...
view the full question and answer

Native replacement for non-native Bermudagrass in Leander TX
October 16, 2011 - We have Bermuda grass. Large patches have died due to the drought and our yard has been taken over by weeds and St. Augustine grass whose seeds must have blown in. Even when the grass was in great con...
view the full question and answer

Replacement for Kentucky grass in Colorado
July 02, 2012 - What kind of grass to replace "Kentucky grass"? It uses too much water. Need drought tolerant grass for the Rifle, Colorado area ("zip code is 81650"). Water bill is way too high, pushing over $10...
view the full question and answer

Deer and Drought Resistant Natives for San Marcus, Texas
February 15, 2012 - Hi there, Do you have a list of plants and ground covers (deer/drought resistant) for the San Marcos area? Much as I love grass, it's impossible with this drought. I'd love to have lots of flowers ...
view the full question and answer

Alternative to swamp sunflower for Austin
June 15, 2011 - Dear Mr. Smarty Plants, I love this forum and have learned so much from it! Do you know of an alternative to Helianthus angustifolius L. (Swamp sunflower) that requires less water and would be m...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center