Host an Event Volunteer Join Tickets

Support the plant database you love!

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
57 ratings

Thursday - June 09, 2005

From: toronto, NV
Region: Select Region
Topic: General Botany
Title: Smarty Plants on cell elongation
Answered by: Joe Marcus

QUESTION:

Why do plants grow faster in the dark?

ANSWER:

In a strict sense, plants do not grow faster in the dark; they grow slower. However, plants seem to grow faster in insufficient light due to rapid cell elongation. In other words, they don't grow faster, they simply stretch. It is important to know that green plants really only grow as a result of photosynthetic processes. Without light photosynthesis ceases and plant tissue develop the characteristic, low-light induced sickly green or white coloration.

Rapid elongation of plant cells in low-light conditions is an emergency response on the part of the plant to return its plant tissues to the light where they can again photosynthesize and live. This would be analagous to standing on the bottom of a swimming pool and stretching to get your nose above water for a breath of life-giving oxygen.

In conditions of total darkness, plant cells will generally expand upward, a process called geotropism. In conditions where a small amount of light is reaching the plant, it will grow toward the brightest source of light in a process called heliotropism. Prolonged exposure to darkness will inevitably lead to the death of a plant.
 

More General Botany Questions

Changing the pH of the soil
January 16, 2012 - Hi, We have a job that has mostly Texas native plants on it. The architect is wanting to drop the pH levels of the soils to acidic levels that we don't feel is good for the plants and the area. ...
view the full question and answer

Cold hardiness zones for plants from Jackson MS
October 02, 2010 - How to search the plant database by cold-hardiness zone? Is it possible to do combination search by zone (not just state?) With the information provided with plant, I do not see the zone listed. Ma...
view the full question and answer

Bird nest fungus in Central Austin, TX.
August 21, 2012 - Hi, I live in Central Austin and have different types of ground cover (such as silver pony foot)in my garden and have noticed huge patches of bird's nest fungi in between and under. Every time it ...
view the full question and answer

Century plant dying after bloom
August 12, 2007 - My century plant is so tall that it is up to the top of the telephone pole top lines that carry our streets electric. I was wanting to know if you knew if I cut the stock off would it save the plant ...
view the full question and answer

Is Phlox divaricata evergreen?
June 27, 2011 - Is Phlox divaricata evergreen?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.