News from Hidden Valley Hibiscus

Did Hibiscus Grow in the Jurassic Age of Dinosaurs?

Mauritius is a tiny, little island off the coast of Africa, and for some mysterious reason, three of the species that make up our modern hibiscus came from that one, isolated little spot on our planet. Even more strangely, all three of these species can interbreed with the five other species sprinkled across the tropics that also went into the genes of the modern hibiscus. And all but one of these five species are also native to distant, small, isolated islands. How is this possible? It is very unusual for different plant species to be cross-compatible, and it is particularly rare for plant species from different geographic locations to be cross-compatible. There is a mystery here that has puzzled us for years!

The hibiscus species that make up the modern hibiscus originated across a huge geographical span

Recently some new scientific information gave us a couple of tantalizing clues to the possible origins of our favorite plant. We have a theory - possibly just a fanciful theory. But nothing else seems to explain all the facts yet, so we thought we would share our theory with you just for fun.

Going Back in Time ~ 100 Million Years Ago

To solve this mystery, we have to go back to the dinosaur days. Modern scientists have thought that flowers didn't exist until about 100 million years ago, during the Cretaceous period. According to the bulk of fossil evidence, flowering plants suddenly sprung to life all over the various continents during this super warm, humid time when the Earth was splintered into many small continents. But evolution almost never happens this quickly, and certainly not on many distant landmasses that are separated by huge expanses of water. Some scientists have questioned this timeline and suggested that very tiny flowering plants may possibly have started well back into the Jurassic period.

Finally, one tiny fossil from Spain has now been dated back to 160 million years ago, right in the Jurassic period. Although it is very, very small, it clearly looks like a flower in all respects! It's an old fossil that was dug up 40 years ago and has been sitting around unappreciated for all these years until new dating methods allowed scientists to establish its age.

So now we get to shift our thinking and look back deeper into the Jurassic period for the origins of flowers instead of being locked into the Cretaceous period. Let's follow our trail further back in time and see where that takes us...

Further Back into the Jurassic Period ~ 200 Million Years Ago

Let's set the stage for the evolution of hibiscus. What was Earth like about 200 million years ago? It was very, very different! All the land on Earth was pushed together into one, single, giant continent called Pangea. The climate was warmer and more humid than today over much of Pangea - a huge tropical paradise. Dinosaurs thrived in this warm paradise, as did plants and tiny mammals. Life grew and flourished everywhere, spreading freely to all parts of the land since there was only one single large landmass.

Countries where hibiscus originated at the time of Pangea, about 135 million years ago. Mauritia, Madagascar, India, and Tibetan China were all part of to the east coast of what is now Africa. Photo Credit: Massimo Pietrobon

This is where we get excited! In the ancient Pangean single continent, Mauritia, Madagascar, India, and Tibetan China were all crammed together in one relatively small geographic area. Talk about a hot clue! Here we have one small spot in the ancient world where 5 of the 8 hibiscus species that blended to make our modern hibiscus could have all evolved together from one mother plant. Could this possibly mean that hibiscus evolved in this one part of ancient Pangea? We had to try to find out more!

After a lot more digging, it turns out that even more emerging fossil evidence is pushing the development of flowers way back into the Jurassic period. Fossils of very early flowering plants have been discovered in both China and Germany that date from the early-mid Jurassic era during the time of Pangea. China! So if flowers evolved in China on Pangea, our little hypothesis is not looking so crazy after all. The earliest hibiscus could have started in the part of Pangea where Mauritia, Madagascar, India, and Tibetan China clustered together sometime toward the end of the Jurassic period.

Hibiscus are in the mallow family, and the mallows are know to be among the oldest flowering plants on Earth. The ceiba tree, a very ancient mallow, is thought to be one of the very first flowering plants. You can easily see below how much these ancient ceiba flowers look like their cousins, our hibiscus species flowers. Hibiscus still have the same 5 staminal filaments that ceiba flowers have, only hibiscus evolved to protect and encase them inside a sturdy staminal column. Amazingly, very little has changed in the basic structure of hibiscus flowers since the days of the ancient ceiba flower.

Ceiba, ancient hibiscus cousin Photo Credit: Michigan State University

Hibiscus liliiflorus

Hibiscus fragilis

So how did the earliest hibiscus end up becoming our 8 special hibiscus species that spread across all across the globe, and why aren't these hibiscus found in other tropical parts of the globe? For that, we have to move forward in time to the warm Cretaceous period, 100 million years ago.

Moving Forward Again ~ Changing, Migrating Continents

The Cretaceous period really changed our planet. The Earth was already very warm, but now it warmed up even more. All glaciers melted all over the planet, and sea level rose by a full 100 meters (328 feet)! The entire planet, all the way to the poles, was very warm and tropical. The new flowering plants that had evolved on Pangea really took off in this new, warmer world. But the extremely high sea level poured water all over the land, and the giant Pangea continent began to splinter into many smaller, separate continents.

Interestingly, Mauritia, Madagascar, India and Tibetan China moved together away from the rest of the land, and became a single island off the coast of Africa! They stayed in this island formation for many millions of years. We don't know what kind of hibiscus they took with them, but whatever it was, it could have eventually evolved, in the isolation of this island, into the 5 related species that we know today. Mystery solved! This finally explains why these 5 species are cross-compatible, can mix their genes, and have not been found anywhere else.

The Cretaceous Period, 100 million years ago India, Madagascar, and Mauritius are still stuck together, moving away from Africa Photo Credit: Christopher Scotese, Paleomap Project

The Cretaceous period was the final burst of glory for the dinosaurs. Our little hibiscus plants could have grown next to Tyrannosaurus rex, Ankylosaurus or Triceratops! Pteranodons flew through the air, and Archaeopteryx was evolving into increasing numbers of birds. It would be an amazing thing if Hibiscus liliiflorus, storckii, genevieve, schizopetalus, and rosa-sinensis could have grown up alongside these giant creatures - or if not they themselves, perhaps a mother hibiscus plant that later evolved into our species plants.

Moving Forward to Modern Times ~ Finishing the Migration of Continents

A few years later, about 66 million years ago, the dinosaurs were all gone. A massive asteroid or comet is thought to have hit the earth and blanketed our sky with dust that created a long, cold winter. About 75% of all species of plants and animals on our super warm earth could not take the cold and died off, never to be seen again. Amazingly, our little hibiscus species were able to survive!

By this time, India and Tibetan China had pulled away from Madagascar and Mauritius, leaving them as separate islands off the coast of Africa. India and Tibetan China migrated rapidly across the ocean until they collided with the rest of China about 50 million years ago. They settled snugly against Nepal and the rest of China, where they still sit today. At this time, India and Tibetan China were in the perfect position to spread hibiscus around the rest of southern Asia, where it is still found today. From there, or from Madagascar or Mauritius, Polynesian travelers could have carried hibiscus in their boats to Hawaii and Fiji where the last 3 species could have evolved.

Could all of this be true? We don't know. We need more research to know anything for sure. It's just a guess on our part, based on many, many hours of research - more than our readers will ever want to know about! The trails led here there and everywhere and many seemed to point to hibiscus possibly being much older than we ever thought before. So maybe it is true, and maybe some day researchers will discover more evidence that moves us along in our knowledge. Whatever the outcome, we'll never be able to think of T. rex again without imagining a little hibiscus blossom growing daintily between his giant toes.

For anyone who is interested in reading our sources, we did a lot of research in four languages to follow this trail. We didn't do an exhaustive review, but we did get pretty exhausted from the searching! We don't want to put you to sleep or drive you to total boredom, so listed below are only our most important and most interesting sources.

Hibiscus Care

Pruning Time!

Here in Southern California and across most of the southern states, pruning time is here. If danger of frost has passed for your area, now is the best time to prune. If you are still in danger of frost, wait until it's a bit warmer. Frost falling on newly pruned branches really slows down their regrowth, and can actually make the tips start to die back and set up an infection.

Ideally, we will all prune just as soon as the frost danger is past, just before the spring warm-up begins. This way, our hibiscus plants can get the full benefit of all the spring warming phase to grow the maximum number of new branches. Remember, the more branches your hibiscus have, the more flowers you'll get, since each branch tends to produce 1-2 flowers at a time on its growing tip.

Pruning makes your hibiscus bloom like crazy!