Alana,

I have seen M. umbellata growing in Mexico IN THE BLAZING HOT SUN, with zero shade. However, that is entirely different from our Blazing Hot Sun - at least where I live. I saw them growing and blooming in April, which is the winter season in Mexico, in about 75 to 80F daytime with guessing lows 60F. Their warmer seasons are around 80F with guessing again lows around 70F

Compared to temps in Texas peaking at 100's F end of July through August and night temps around 70F

I will be curious what Ron and Joseph have to say as well.

Emma

Thank you Emma. I may have read that about a particular plant and may be misapplying it to umbellata. I can't find any reference to support it so I may have to experiment.

I found this species growing alongside a roadside in short vegetation and in rocky type soil. It was baking hot there too, but the location was in a region known for more frequent rainfall (i.e. on north side of the cordillera that runs east west in the midline of the island).

Hi Alana,

The container size is good and as long as you can keep the plant hydrated by a water reservoir under the container or any other method of shielding the container from being baked by the sunlight e.g., like those water filled shields that are advertised to protect tomato plants grown in containers from the sun...or covering the container with a very reflective material like aluminum foil or the heavy duty water resistant reflective mylar...so , if you can protect the container the plant should be okay in the sun.

Plants that are planted directly in the ground do not have the root system heated in the same way as plants grown in containers where the root system is above the ground and more susceptible to the baking rays of the sunlight upon the contents of any container.

A mulch to cover the container surface that will help to retain moisture but still allow good aeration would likely be helpful for growing the Merremia umbellata.

The difficulty with the Merremia umbellata is that the wild strains are strongly tending to be acclimated to flower very late in the season when they days are very short and so far few have had luck with getting the plants to flower...

Good luck with the Merremia umbellata.

regards,

Ron

Thank you Joseph. It may be that humidity is more of a factor than air temperature.
I use mylar in the greenhouse to reflect sunlight in winter-I never thought about using it to reflect heat away from outdoor containers. I'm going to try that with these.
Thanks Ron!
Alana

Alana, that will be fun to see if you can get blooms.
I'm think about growing the M. umbellata too and see what luck I have.
Thanks for the tips, Ron
Emma

Hey Ron,

Is the under-container water reservoir similar to the wicking system used in African violet culture?

Joseph

I've tried this from seed a couple times. It sprouted easily and grew but I never had blooms. I tried wintering it over in the greenhouse one season but had to cut it back so much to get it in that nothing happened. I hope you are able to get it to bloom.

Joseph - I'm not familiar with the wicking system used for african violet culture ;
I was referring to a basic water reservoir under the container as this helps keep the container hydrated and helps to prevent over-heating when the heating rays of the sun are shining intensely directly on the containers and plants.