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HomeHomeWildflower Seas...Wildflower Seas...TexasTexasEarly Blooms: What Does That Mean for the Spring 2019 Wildflower Season?Early Blooms: What Does That Mean for the Spring 2019 Wildflower Season?
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2/12/2019 2:25 PM

Early Blooms: What Does That Mean for the Spring 2019 Wildflower Season?

For nearly a month now reports have been coming into Texas Wildflower Report ( ) or in private message about sightings of early bluebonnet and other wildflower blooms. Photos are now circulating showing parts of the Big Bend area in full bluebonnet bloom which is several weeks earlier than usual for that region. A friend sent me a photo of a field of bluebonnets in bloom near Freer, Texas which is well south of San Antonio, an area that usually will see mid-March as the beginning of their bluebonnet bloom.  What is happening this year and does this mean the Spring 2019 Wildflower Season will be much earlier this year? As I mentioned in the 2019 Outlook, it does appear that roadsides and areas within urban heat islands along I-35, I-10 and I-37 will bloom much earlier this year and likely much earlier than fields. This means we might see a split season where the roadsides and urban areas peak well before the fields do. This is not totally unusual, especially when we see a warmer December and January which we did this year.
According to the latest NOAA Enso report, the USA just went through an anomalous ridging that put parts of the USA into warmer than normal temperatures. Look at this slide from the ENSO weekly report 2/11/2019 that shows most of Texas in much warmer temperatures for the 30-day period prior to 2/9/2019.

US Temp and Precip Last 30 days

Why would this make a difference to our bluebonnets? Our bluebonnet species are winter annuals. Winter annuals germinate in the fall and go through the winter as small plants called rosettes. Most winter annuals need a cold spell to stimulate or induce flowering in the spring. This need for the cold spell is called vernalization (there is some debate about how, why and if, but the general consensus is they need the cold). I have not yet found any references that state exactly how long a period of cold that our bluebonnets need. One source indicates that the vernalization requirement can be four to 12 weeks for winter annuals. And from other research, it is clear that plants do not just respond to short periods of warm temperatures that break up a winter. So, the plants respond by flowering only after a specific time of cold followed by a specific time of warming temperatures.  It appears parts of Texas went through a period of cold that was followed by a period of warm temperatures in the past 60 days. It could be the vernalization requirement for bluebonnets in those locations was met and the warm period following was long enough to start the process of flowering.  Another wild thought, is that we might already be seeing a new adaption in at least one of our bluebonnet species that will be blooming earlier as our winters are warming – it is wild thought, but it is already happening with other species of wildflowers in California.

Ok, but what about the next 30 to 40 days? According to the NOAA 3-month seasonal outlook, Texas should have an equal chance for normal precipitation and temperature.  NOAA ENSO is also showing a 65% chance we will see an El Nino develop and last through the spring.

US Seasonal Outlook Feb-April 2019

This means there should be plenty of moisture available, moderating temperatures and plenty of sunshine mixed in.  If this holds true then we should see at least the fields hold off until the usual time for them to bloom, but even they might start a bit earlier. I still think based on all of the reports of blooms that the roadsides will bloom earlier this year, especially along roads in the urban heat islands. Adequate rainfall, plenty of sunshine, and moderate temperatures typically means thicker and longer bloom times for all of our spring wildflowers. Hopefully, that is what develops in the next 30 to 40 days and into spring.

NOTE: The 2019 Spring Wildflower Season Outlook and our Wildflower Updates are not a forecast, they are merely a look at what the data and past record suggests might happen or happening. Attempting to forecast Texas weather or wildflower seasons is a futile effort laced with disappointment. One would have a better chance of predicting the Final Four one year out than to try and predict Texas weather or wildflower seasons. But we try our best to use the data to give us a clue about how the season might develop while remembering that one day it could be snowing in Texas and the next day be t-shirt weather. And Texas weather goes hand-in-hand with how the wildflower season will develop.



HomeHomeWildflower Seas...Wildflower Seas...TexasTexasEarly Blooms: What Does That Mean for the Spring 2019 Wildflower Season?Early Blooms: What Does That Mean for the Spring 2019 Wildflower Season?