En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Inducing flowering out of season

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
Not Yet Rated

Friday - June 22, 2007

From: Vineland Station, ON
Region: Canada
Topic: General Botany
Title: Inducing flowering out of season
Answered by: Joe Marcus

QUESTION:

We are currently conducting research on insect transmission of a plant virus to flowering weeds. Is there a process to trick biennials into flowering in their first year?

ANSWER:

There probably isn't a one-size-fits-all answer to your question since all biennials are not created equally. However, in general biennials begin growing one year - often in late summer or fall - and typically form a basal rosette. In late winter or spring of the following year, they flower. Bud initiation is typically dependent on accumulated hours of cold temperatures. When the plant has been exposed to enough hours of cold temperatures, the plant will initiate flower bud development. When the weather warms sufficiently, the plant will produce flowers, often on a tall flowering stalk.

Nurserymen have long taken advantage of some plants' response to cold temperature bud initiation to induce flowering out of season. Valentines Day tulips are a good example of this practice, though tulips are not technically biennials. In practice, greenhouse growers accomplish this feat by keeping vegetative-stage plants in in cold storage for a predetermined period of time and removing them to a growing area a specified number of days before they are to be marketed.

For your experiments, if biennial seeds were started early enough in the year to allow for sufficient time (along with other required conditions) to grow the necessary basal rosette, then the plants were placed in cold storage for long enough to accumulate the chilling hours necessary to induce bud initiation, then the plants were removed from cold storage and placed back in a growing area, it would be possible to complete a biennial's growth cycle in one year. Some trial and error might be required to determine the optimal mix of pre-chilling, chilling and post-chilling days and other conditions necessary for success.

 

More General Botany Questions

Effect of epsom salts and gray water on plants
December 04, 2007 - We live in Phoenix where water is a precious commodity. We have decided to use as much of the gray water as we can for watering our garden, shrubs and trees. One of the suggestions we heard about w...
view the full question and answer

Gardening books for Austin and Central Texas
June 09, 2008 - Hi, I'm looking for a book for my wife. She is a beginning gardener here in Austin. Do you know of an ideal book or two that covers vegetable gardening and gardening in general in Austin/Central Tex...
view the full question and answer

Clover in grass in Marysville WA
March 05, 2009 - I noticed clover growing in my grass and know that this is a sign of poor nitrogen in my soil. I would like to know of some native plants / shrubs that I could put near my house in Washington that ...
view the full question and answer

Effectiveness of house plants for removing household air pollution
January 30, 2006 - I have heard that there is a combination of house plants that will increase the oxgyen in your home. Could you please tell me the names of these plants? I think there are a group of four of them. ...
view the full question and answer

Drawings of Illinois native wildflowers
July 15, 2006 - I am looking for line drawings of Illinois Native Wildflowers to use for educational material for visitors to our new City Park. We plan to have signs throughout the park describing how Native Americ...
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