Euphorbia Pulcherrima - Poinsettia Plant Blooming in Balboa Park, San Diego, CA.

Named for General Joel Roberts Poinsett...a botanist and physician..

Sorry ...I called him General...but on doing some research he was Secretary of War...also special agent to Mexico where he first saw the poinsettia...was also part of the organization which was part of the founding of the Smithsonian. Interesting man...can see from this pic, D1, why, as a botanist he would be interested in this plant! very striking...and blossoms in the winter! So how is it that this one is blooming in June???lol.

That's the million dollar question - it's just very weird seeing this blooming at the same time as the jacaranda!! Over here in Oz it blooms in June but that's our winter - this one might be a mutant.

Or maybe it's from downunder!

Lori, Bernieh:

I commented earlier on the last photos...the 3 plants in this area are not the only ones I've seen in full bloom around the city. That's the strangest thing. I'm not sure what causing them to bloom...because they must have short days and longer nights to set the bracts and flowers.

I'm sure there's no lack of light in an urban area! could the bloom trigger have a moisture component? and the moisture availability could outweigh the darkness requirement? It's an interesting puzzle. I noticed too that the brachts don't look as large as we see in winter. could it be a spontaneous cross with something else? maybe the desert euphorbia heterophylla? You mentioned some cloudy weather recently could they be that light sensitive???

Lori:

Actually, these plants "must" have photoperiodism in order
for them to bloom.(so I thought. lol). The bacts are pretty large
and the plants is 7 feet plus tall.

The cloudiness was not dark and constant enought to provide
the darkness they need. They want at leat 13 to 14 hours of
pitch dark...even porch lights can cause them not to bloom.

i remember a story I heard about a grower who had a greenhouse of poinsettias that he was readying for market...couldn't figure why they weren't turning... turns out there was a lighted sign nearby that was just enough light to put them off!!

ours still alive since Christmas.Can anyone tell me when exactly they need to go into the dark,and for how long !

I know that you can "time" it... Delonix1 says 13 to 14 hours of complete darkness per night...but for how many nights?

Thats what I wanted to know..For how long !

Bonkersbon:

Poinsettias set their flowers based on light cycles. To force a poinsettia into a Christmas bloom, you need to provide 12 -14 hours of total darkness every day, beginning in late September or early October. If the 12 - 14 hours of darkness at night is interrupted with light, it generally will not bloom.

Thanks for this info Delonix....keen to do this as never had poinsettia survive so long ! Will follow your advice....many thanks !

Bonkersbon:

You're welcome! and Good luck!

Bonkersbon:

13 - 14 hours per night until you see the bracts develop.

Then I think it's okay to keep them in more light.

Thanks Delonix1, Much appreciated.

Lori:

You're welcome.

Thanks again Delonix...your advice has been invaluable !

Bonkersbon:

You're so welcome! Anytime.

Delonix....about to put poinsettia in darkness for 14 hours per night.in dark cupboard.Does it have to stay there in daytime too or can it come out then go back in at night? Sorry to have to ask again but quite excited it has survived all year !! Many thanks.

Bonkersbon:

It can come out during the day...however, it must have 12 -14 hours of uninterrupted darkness until the bracts and flowers have developed.

Thanks again Delonix...will post a pic if successful !!

Bonkersbon:

You're welcome! Good luck! : > )