Flower Bud Induction Overview and Advisory

Flower Bud Induction

 

NOTICE FOR CITRUS EXTENSION AGENTS & SPECIALISTS AND GROWER NEWSLETTERS
The following information has been developed as part of the Decision Information System for Citrus

L.  Gene Albrigo, Horticulturist Emeritus
Citrus Research & Education Center, Lake Alfred, FL

 

Archives of past Flower Bud Induction Advisories

 

Flower Bud Induction Overview and Advisory
NOTICE FOR CITRUS EXTENSION AGENTS & SPECIALISTS AND GROWER NEWSLETTERS
The following information has been developed as part of the Decision Information System for Citrus

L. Gene Albrigo, Horticulturist Emeritus
Citrus Research & Education Center, Lake Alfred, FL

FLOWER BUD INDUCTION ADVISORY #2 for 2017-2018-12/1/17

This is a service to our citrus growers posted on the CREC website. The indicated Expert System on intensity and time of bloom can be accessed at the designated Web Site: http://disc.ifas.ufl.edu/bloom
If you are not familiar with the website and flower bud induction in citrus you should read the overview section in the first advisory this year.
The on-line version has been updated so that you can shift from one FAWN weather site to another without back tracking. More FAWN sites have been added to the menu. Another added feature is that the total accumulated hours is now listed as is the projected hours to be accumulated the following week. Additionally estimates of the start of bud break for psyllid spray timing and 5-10 % open flowers to aid in managing psyllid sprays and bee movement for the bloom period will occur with the first initiation of flower bud growth.

Flower bud induction status in 2016-17 for the 2017-2018 crop- In this La Niña winter, with less cool temperature accumulation and rainfall expected, citrus locations currently have accumulated moderate inductive temperature hours, < 68 degrees F, of 300 to 500 hours from southern to northern areas, respectively. The next 7 days will have low cool temperature accumulation of 30 to 70 hours, south to north. The totals of 350 to 550 hours after another week would be 1/3 to ½ of the total we would like to have for a good economic flower induction level.

Accumulation of cool temperatures and prevention of growth during a fall or winter warm spell is very important for good 2018-19 citrus production. The weather needs to continue to stay cool to prevent early initiation of bud growth, which can occur with daytime temperatures in the mid-80s for 7 to 10 days after accumulated cool inductive temperatures have reached 450 to 500 hours. Unfortunately, we have had several days of 80 degree daytime highs and seven more days are predicted by the weather service. Lows are expected to be at near 60. With the low level of induction so far in southern and central areas, we must hope that an initial set of buds do not start growth. It is too bad we cannot apply drought stress to stop initiation of growth at this time. See the first advisory for why this is dangerous with HLB affected trees.


If you have any questions, please contact me (albrigo@ufl.edu).