Contact Us Host an Event Volunteer Join

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
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

Native North American bulbs
August 19, 2011 - I saw your list of 4 lilies native to the Northeastern United States, which was very helpful. What other bulbs are native to North America? Although I garden in Connecticut, I am interested in learn...
view the full question and answer

Which one is huajillo and which one is guajillo?
November 19, 2013 - Recently I attended a field trip to the Leonard Garden at the Kleberg Institute in Kingsville. I took a picture of a tree that was referred to as Tenaza or huajillo. Later I took another photo of a ...
view the full question and answer

How is native range changed in the scientific record?
March 28, 2011 - I am accessioning Pachysandra procumbens for the Baker Arboretum. These plants were made from cuttings of a native stand here in Warren County (Western KY). How does the record get amended to...
view the full question and answer

Disappearing sunlight in Phoenix, AZ
September 29, 2009 - I live in a condo in Phoenix, AZ with a north facing patio that goes out about 10 feet and is 20 feet wide. During the summer months there is a span of 1 foot in the front that goes the 20 foot length...
view the full question and answer

Grafting stone fruit
April 02, 2009 - Do you know of anyone grafting the new low chill stone fruit trees to the Mexican plum to minimize cotton rot? Or would it even work?
view the full question and answer

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