Seedling Propagation of Thunbergia Grandiflora

Propagating Thunbergia grandiflora (Skyflower, Bengal Clock Vine or Blue Trumpet Vine) from cuttings is much more difficult than we thought. With the cuttings that we took from a nearby source, survival rate was a disappointing 0%. It is for this reason that we decided to head for the hinterlands of Mt. Makiling.

Since one of our daughters is studying at UPLB, DH already noticed the vines among the trees in our many visits to the campus via the UPLB shortcut. And yes, they were quite floriferous with the lavender-blue blooms. Unlike DH, I generally don't notice these things. Somehow, DH has this keen ability to hone in to surrounding flora wherever she goes.


So after we parked near the St. Therese Chapel, DH goes "hi-ho, hi-ho" with her tools all packed inside a sack (see above photo). We weren't after cuttings this time. No, we were looking for seedlings that we could dig up or cut and then replant in our garden.



She was armed with the usual: her trusty old garden trowel, pruning shears, a scythe and even a machete. We even brought along a garden pick-and-hoe combo but decided against putting it in the sack. Her sack was getting too heavy.


Invasion of Thunbergia Grandiflora (Skyflower)

How did we know that the plant was indeed Thunbergia grandiflora? Aside from the obvious plant similarity, I learned from various student and university (UPLB) fora on the internet that this plant species dominates among the vines in the campus. Not only that, I came across internet articles mentioning Thunbergia grandiflora as an invasive plant in the forests of Los Banos, particularly Mt. Makiling. UPLB of course is nestled at the foot of this mountain.

Here's one on plant-bioinvasion. The author, Nestor Baguino, writes:

...the author believes Mt. Makiling forest is facing a serious problem of quick bioinvasion in gap and open areas for examples by Paper Mulberry (Broussonetia papyrifera) and Skyflower (Thunbergia grandiflora)...

If you think that's scary, Thunbergia grandiflora is an invasive and pest plant in other countries as well, like Australia and Hawaii. Thunbergia grandiflora has been shown to smother rainforest in north-east Australia at a rate of approximately 0.5 hectare per year. Here's how the vine eventually covered a landscape in Queensland. (Sorry for the blurry photo that I only took from the net.)



Growth of Thunbergia Grandiflora Seedlings (Skyflower, Blue Trumpet or Bengal Clock Vine)

There were no vines along the narrow road where we parked the car near the Math building. There used to be, so I thought they were cleaned up and removed.



DH went farther towards the creek with her sack of tools. After around 30 minutes, DH came back.

Here she is showing off her loot of Thunbergia grandiflora seedlings inside the sack, plus her deadly weapon.


We really didn't think much of digging up these seedlings because these vines have become weeds for the campus. How did the seedlings grow in the first place? DH theorized that the seedlings were either suckers or seedlings that sprouted from natural soil layering.

Here's how suckers are formed as new plants.


And here's how a process called soil layering allows new plants to be formed. A natural process occurs when the vine's long branch falls to the ground and gets buried by dirt and debris.



Actually, some vine branches become too long or lanky and will just naturally touch the ground.


In both cases, you will need to cut away the seedling from the mother plant.

When we arrived home, DH set the 7 seedlings in black plastic bags.



First Flower of the Thunbergia Grandiflora

Surprisingly, all of the 7 seedlings survived. Now it seems, I've got my hands full in building additional trellises for all seven vines.

After 4 months from the time the seedlings were transplanted, the first Thunbergia grandiflora flower appeared. The seedling in the garden pot below thrived well and grew fast on a sturdy container trellis that I built. (Here's how you can make a standalone trellis from bamboo.)


I pruned this Thunbergia grandiflora vine once a week, knowing I needed to contain it as much as possible in its standalone trellis. And at its height of just over 3 feet, I was pleasantly surprised that it gave us its first bloom ever. Truly, a welcome beautiful addition to our garden.



Go ahead, post your comment below!

Jan Pearce said...

Great information on this lovely vine. I however have unfailing success rooting these every fall before the first frost. I cut mature vine segments toward the blooming vines and leave at least two leaf segments at the end and cut the leaves off of two joints. I place them in a clear or green glass with water in a sunny window sill and 80% develop roots and have even grown a vine and flowered while in the window sill! I live where the frost bites them back so I get new cuttings every fall just in case they don't survive. Change the water every 2 weeks and enjoy!

Blackdove said...

Thanx for the tip, Jan. I'm slowly discovering that there are so many plants that can be effectively rooted in just plain old water.

bethreymatias said...

Thank goodness, I finally found someone who shared the same interest on this plant. Where can I buy this plant??? Can you sell me a thriving cutting of yours? Please? I can go to your place wherever you live. I am at QC. I would appreciate any response from you. Salamat po!

Blackdove said...

Hey there, bethreymatias. I'd have to check my garden. I have the feeling I have a few stable seedlings in seedling bags growing somewhere. How many do you need? Where are you in QC?

bethreymatias said...

Thank goodness my post went through! For awhile I thought it didn't push through because html was somehow required.

Did you know that I was so thrilled reading your story that I am tempted to got to UPLB because I read through your post you got your cuttings there. Oh, please sell your cuttings to me! I have been to Seddling Bank when they were still in EDSA looking for that plant which I just see so often on the sidewalks occasionally. I would need at least 4 please if you have that many. HOw much would you sell it? Could you sell it with thriving roots? PLease? I live here at New INtramuros Village. Are you staying in QC as well? :)

Blackdove said...

Yes, it did. I normally answer all queries to my blog. I didn't realize though that html was required(?). You have to describe that to me please. I need to review/revamp the blog.

I found 5 T.grandiflora plants in seedling bags. They're all healthy but not flowering because they're in an area where there isn't much sunlight.

Let's communicate via email na lang. I'm at blackdove212 at hotmail dot com.

Anonymous said...

Does anyone know if there is an insect that could use this as a host plant (other than Aphid) since it grows so fat it is hard to control but if there was a voracious eater like the swallowtail for the dutchman that would be great.