Mine are doing the same here including my bromo's so I dont have an answer either

Stress can cause plants to flower. Whether it be a cold snap, fire, a hurricane/tornado, drought, chemical spill.

The plant realizes taht there is something not typical for it's regular metobolic and seasonal activities. Thus, the response by a plant is "my death may be imminent, I need to ensure survival of the species". Thus, flowering occurs with an attempt to get viable seed out there before the mother plant dies.

But, you have some plants that naturally flower in a dry season as compared to the high sun/wet season that we'd think would have them flowering their heads off. Comparatively speaking, the temperatures are warmer in November as compared to the same day length that happens in late January. SO, plants may still find it warm enough to flower "comfortably" but not so in late January (or vice versa).

It looks like my Aristolocia litoralis is just about done flowering now. I was amazed it could flower all the way into December, but it had a late start. Some of my ceropegias are starting to flower outside too; I'm sure from the cold stress.
Where in CA are you Mike? I'm in Placentia, CA.

Robert

I agree with poi (above). Stress does sometimes cause certain plants to flower. I have observed annuals doing this in fall or during an early cold spell or during dry spells. Many perenials also do this. Some plants react to changes in day/length (light) like poinsetta and other tropicals. Bougainvillea does seem to flower well after a dry spell. Some people even stress thier bougainvillea by holding back water and then watering to induce flowering. I have many tropicals blooming now like bougainvillea, brugsmania, passiflora etc. Also my moonflowers are going crazy since the weather started cooling down at night. Bananas and hawiian ti plants are sending up new shoots.
I have searched for the cause of plant stress and flowering. I would like to know what the "trigger" is. Does the plant send out a certain hormone or chemical to induce the reaction (flower/seeds) as a direct result of some sort of stress? Most likely, but I don't know what it is exactly. It would be interesting to find out.
~SJN

Finally recuperated from Thanksgiving; don't know why I thought I'd have time to log-on over the holiday weekend :>

Poiu, I have to agree that stress probably has a lot to do with what we're seeing. But, some of my tropicals had already been moved into the greenhouse and are not really experiencing the cooler temperatures, although I'm not doing anything about the shorter day length. I wouldn't figure that tropical plants that have never experienced these types of pressures would have evolved adaptations to deal with seasonal changes.

Robert, I'm in the Sacramento region and we're a bit cooler than you in the winter months. We usually get a few light freezes by the beginning of November, but usually don't get colder that 30 F anytime during the winter.

Sultry, I hadn't begun holding back on water until after I posted last week. I figured that as long as they were still growing... We had a freeze on Thanksgiving night and that pretty much took care of the bananas and Brugmansias that I winter outdoors, (they'll grow back come spring). I'll be curious to see if the bamboo keeps getting taller or if the existing shoots continue to grow when temperatures begin warming up at the end of February.

I would expect the triggers that you mentioned in plants accustomed to seasonal variations, but it must be something latent in tropical plants.

Since my last post, the Coral Tree, (Erythrina Crista-galli), and a tropical Ginger have also begun to put out flowering spikes. Only three more months until spring!

Mike

Actually, tropicals have various "triggers", too. Stresses being a general category for discussion. Temperatures (also the nighttime low temps), humidity can be triggers.

The "seasons" in the tropics are wet and dry, whether it be in a coastal plain to mountainous area, Mediterranean clime, et al. ALso, closest the equator there are 2 "high sun" periods, when sun intensity is strongest as rays travel from Tropic of Cancer to equator to T of Capricorn and back to equator. Often people note that animals sense things so much more acutely than us preoccupied humans. I'm sure plants are much more in tune to the subtleties (spelling?) to very strong light versus 75% of that, etc.

Then again, there is the photoperiod. Brugmansias, for example, are well documented for their flushes of blooms seemingly corralated with the lunar cycle (some seem to flower afer the new moon, others consistently after the full--?). Since there is not a 4 season cycle over 12 months in the tropics, i oculd readily see that a plant has genetic codes that have their own species (or generic) cycles--whether it be driggered by day length, an exposure to a heat or cold stimulus/stress, etc--that may revolve every 30 days, or 3 months...

Some plants, based on their location in the rainforest (howmuch sun they actually receive on the forest floor) may also be the trigger of flower or vigor. Perhaps the light intensity of the sun's rays in November matches the light level needed for floral initiation. For example, maybe in nature an aroid is in deep shade all year (in the Amazon basin) until the height of "summer", when the few rays that come down through the dense overstory is now at say, 1000 footcandles. Take it out of the rainforest and place it in a temperate zone garden that has an overstory tree (but not as dense as a tropical canopy). In this temperate garden with the less dense canopy, the aroid may always receive 1500 footcandles (too high for it's genetically disposed trigger of 1000 footcandles to produce flowers). But, as the sun diminishes towards winter, perhaps the sun is weak enough to pass through that same sparse canopy to BOOM! match that 1000 footcandle threshold that would be achieved in the rainforest, and all of a sudden it flowers--in the seemingly "wrong" season.

Now, adding that you're in central northern CA and I"m in southern FL, and I too have noticed that the Alpinia purpureas are flushing brand new floral spikes, that there is perhaps something genetic with photoperiod. But I'm sure there are other plants that may do some "atypical" things from a FLoridian standpoint there in CA based on humidity, soil pH, or a host of other things that really need to be isolated and researched.

My dwarf Carrie mango is producing flower buds, and it is about 35-40's outside. Maybe a dip in cold weather triggers it (longans need a slight dip before they bloom in spring). But I have to really baby this mango, because it doesn't realize the weather is about to get much colder.