Pink Jasmine: where does new growth originate?

I'm curious.

I'm unable to determine the "origins" of new season's growth following the Spring Flower. The vine is, as many of you no doubt know, packed with green stems of the passed flowers. I would like to truly "train" my vine so as to have a bit more control over it's path across the metal fabric fence. But I simply cannot find out what happens with these "bundles" of stems. I mean . . . this vine is so "woundaround" that it is impossible for me to figure out earlier patterns.

The photo here shows the entire tip of a branch with numerous flower stems. The next photo is the same branch closer up. The displays the earlier branchlet (?) a tad long and without apparent flower stems (top right), with several pair of flower stems and new growth tucked in with each pair. When I look at similar branchlets the distance between each pairlet(s) is considerably longer . . . which causes me to consider that the branchlet between them grows as the new branchlet develops. How's that for a convoluted sentence? My botany ignorance is certainly evident here, eh?

Would someone please reduce that ignorance for me? And if training this massive cloud of wondrous vine is neigh impossible, at least my curiosity will be satisfied.

Oh, and would simply pruning this back to the fabric fence along the length of the fence, fill in the lower fence? Or is growth always at the upper fence despite any pruning?

TIA to my wondrous gardening friends,
Linda and The MopTops

Here's the close-up. Some of you might wonder if I have a life outside of gardening. Well I do [chuckling]. But gardening is a big part and I'm filled with curiosity and ignorance.

Wisdom?

Linda

i would like to know the answer too. i want to try to train up some jasmine so that it is a little thinner, not so bushy. is this unrealistic? new growth is starting now.

Hmmm, wonderearth, no wisdom here. Bummer!

My Star Jasmine is easier to "pick apart," as it were, to watch new growth. I regularly snip new growth with my fingers to encourage growth elsewhere (I think). But the pink jasmine is much more difficult for me to "pick apart."

When I get home from work this evening I'll try to move the thread elsewhere to see if another forum is more appropriate for the question. Or . . . if you wish, you might also do so this afternoon.

Later . . .

Linda

New growth can emerge from the roots or leaf nodes. All plants produce a growth hormone called giberellic acid. The growing tips of stems produce an anti-giberellic acid which suppresses the growth of secondaries farther down on the stems. That's why when you cut something back, new growth starts at the leaf nodes because cutting off the top which contains the growth suppressant allows the giberellic acid to stimulate new growth.

I just noticed this is the beginner forum .. leaf nodes are the little bumps on stems where leaves used to be or still are.

X

This message was edited Jul 15, 2009 10:03 AM

Aaah, X, yes, when I look at roses, "dead-heading" I am very aware of the nodes from which the next flower will emerge. I refer to the leaf joint with that bump as my pregnant joint. Some of them are already quite "fluffy" with life, others less so. I love finding the quite fluffy ones.

So, okay, it makes sense then that the old tips suppress new growth further back along the branch. The old tips want to keep control, it would seem. Hmmm, does cutting further back down the branch promote more growth and more growth further back down the line? So if I cut more severely then there would be more new growth and much of it might be further back, closer to the main stem/trunk? I never thought about there being an "anti-growth" hormone stifling growth. Does it stifle growth throughout or simply further back down the line?

So pruning or "topping," for example, my pink jasmine might promote growth to fill in the center of the vine, reducing the cloud effect that pink jasmine produces? This particular vine throws out an enormous amount of growth at the end of the stem, throwing out what in effect appears to be a cloud atop the wire fabric fence. Cut that cloud off come fall? or spring? and it will fill in from closer back to the origins at the ground?

I would love to fill that space in some, then allow the cloud to appear every couple of years.

Am I making sense here?

Linda

Cutting off the tips will stimulate growth farther down. The "anti-growth hormone" doesn't suppress it completely. I have noticed that secondaries, new growth at the leaf nodes does occur in a lot of vines when they get to a certain point away from the primary growth point - the growth suppressant is probably a lot weaker.

Growing leaves, stems, flowering and creating seed pods use energy in a plant. There are a lot of factors that tell a plant to stop growing and start flowering. In some plants it might be the angle of the sun, how much dark there is, temperature, moisture levels in the ground, even how much stress the plant is under can make it start flowering.

When I prune things to make them fuller, I always try to root what I prune off.

X

Linda,

This vine's natural tendency is to be a very thick, dense, agressive vine. If left untrimmed, it can very easily get out of control and invade just about everything in it's vicinity. It will build up a huge amount of dead wood underneath the new growth and in time, there will be layers upon layers of it.

Keeping it "flat" to a chain link fence or similar type of trellis, IS possible, but it will require constant trimming and thinning.

You can do either of the following to keep it under control:

1.) I used to have one growing on a wire mesh type support. AFTER it bloomed, I would go along and clip off the dead blooms. (You'll see that the old blooms will have a dead brown stem where they attach to the main runners. This is where the new shoots (foliage) emerge.)

I would cut off ANY brown stems I saw...regardless of if they had old blooms or not.

Depending on how established the vine is, there can be a LOT of this.
It's also very time consuming to do, but if you don't, it will become a massive thick mound of new growth intertwined with old growth.

After you've thinned out the dead growth, it will resprout amazingly fast, then you can direct the new growth where you want it to grow...but you have to keep up with it or it will get away from you in no time flat.

2.) Since you live in the opposite type of climate as I do, you can also do this: AFTER it blooms, and BEFORE your temperatures get really hot, you can take an electric hedge trimmer and shear it back to three inches or so of the fence (being careful not to let the blades of the trimmer make contact with the fence.) Or, you can use a hand held hedge trimmer to do it. Then you can see where the dead non productive growth is and remove it.

It's pretty hard to kill one of the vines once they're established. It may not be prudent to do this in the middle of summer where you are due to the heat. We have one rental property that has this vine along a chain link fence like you do. I use the hedge trimmer on it after it blooms then let it resprout. It hasn't hurt it one bit, but I do it in March.

If you don't keep up with keeping it flat to the fence, you're going to have a massive build up of undergrowth and pretty soon you won't be able to walk around the fence. This vine will pretty much send out new growth wherever it's been cut.

I don't know how many of these you planted, but one plant can easily cover about 50 feet of fence, if not more.

Oh my, JD, you certainly went to a lot of effort to help me understand this. What a blessing you are. Thank-you so very much.

So, OK, I planted a single plant on each side of the enclosed garage driveway, along with, on one side, Clematis and a passion flower to create a window of sorts to open the patio up to the drive, and the other side has a Mary somethingorother rose dead center. Both sides of the driveway have a Star Jasmine in deep shade at one end, with a Sally Holmes at the other end closest to the garage/house. Clearly, I must maintain control of the pink jasmine. There are, then, only two -- one on each side of the driveway. But they certainly entertain the eye with their huge clouds of growth atop the fence. The vines are hmmmm, 4 years old, it seems to me.

I dug up underneath the cloud at the top of the fence today. The vine underneath is in pretty ragged condition. It is, of course, showing no new growth and what is there is thinly leafed with heavy stems moving about without design. I hear ya, when you speak of our temperatures right now (it's 109 at 6 p.m. UGH) and the inadvisability of pruning heavily right now. So, should I wait until Spring following the flowering? Or can I cut it back heavily in Fall? Hmmm, I want to go out tonight and strip that puppy down to the wire, but will restrain myself.

And, Xeramtheum, that's very interesting information about the hormone growth inhibiting function of the outer flower bouquets. That is very helpful to have in my brain-based pruning encyclopedia.

Again, thank-you all so very much for taking the time and energy to educate me and wonderearth about how to manage the jasmines.

Fascinating stuff, huh?

Warmly,
Linda