Climbing Hydragea, no growth or blooms after nine years

Nine years ago, a professional landscaper planted a climbing hydrangea on a sturdy trellis on the south side of a building on my property. The area wall is pretty sunny but it is tempered by some shade. The soil is the typical northeast acid, I assume. (However, the plant is next to a foundation of the same age) I live in central New Hamspshire.

I have patiently waitind for some growth and blooms and have none. The plant looks healthy.

What would an expert gardener do in this case to try to promote both blooms and growth?

I am absolutely not an expert gardener, but I have had a little experience with this plant. I bought one two years ago and planted it at the base of a telephone pole that sits right in the middle of my yard. Yes, it's lovely to look at, hence the purchase of the climbing hydrangea to hide it. I watched the hydrandgea not climb for two years, not bloom, and in general not do anything but look exactly the same as when I bought it. This spring I moved it to a shadier location and within three days it had perked up. It's been three months since the move and it's bloomed for the first time and is really starting to climb. Maybe a move for your plant would also work?

First I will tell you that Hydrangea petiolara is one of the slowest plants to get established. Most of the time it takes about 7 yrs on average, at that time you will get some growth and flowers. They are very much worth the wait. In the mean time give the plant some triple phosphate 3 times a yr fall, spring and mid summmer this should give it a jump start. And regular feeding of miracle gro or other fertilizer. Hopefully you will see flowers next yr.

Seven years is looong time - you certainly have mastered the patience part of gardening. I planted one on a split trunk pine tree in full sun probably 9 years ago and it is probably 25 feet up those trunks today. Spectacular. It did nothing much for 3 or so years, but then the magic happened. The blooms this year were spectacular and so fragrant the patio and beyond were perfumed. They do like water and appreciate your keeping any weeds away but I'm sure you do those.

Thanks for the advice. I am not familiar with triple phosphate, what is it and why should I use it?

Phosphorous is the middle number in fertilizer it encourages root develpopement and flowering. Triple phospate has just phosphorous in it, most flowering trees,shrubs and vines(perennials too) use a lot of it and if it is deficient you will see very little to no flowers. Make sure that it is getting enough water also.

Thanks, I have applied triple phosphate and will post if I get a response that is different than the usual. This year water certainly has not been an issue.

I'm not sure the shade/sun exposure is as much an issue for H.p. as water. In less sun they stretch out, and in full sun they are very dense and have woodier branches. I had a 15 yr old - about 14 ft high one growing in a very damp location in full sun and it bloomed nicely. Our soil is notoriously heavy clay and poor in nutrients. We had to move it after the 10 ton mulch truck backed into the pole set in cement that it was on and broke it off - I was annoyed beyond belief to have to do all that work because of those louts. Besides the pole damage, the plant had a 3" trunk on it that broke off at about 5' up.
My main concern has been to keep it alive and get it established again. I planted it beside a full grown Paw Paw tree and mulched it very heavily. It gets some morning sun and then the mid-late afternoon sun but the main issue is being beside tree roots and moisture competition. I have to work to keep groundcovers away but I've used Mighty Plant, home made compost, Messenger, and plenty of extra water to get it established this year. It repaid me not with blooms this year but with new vine growth. Someday I'd like it to climb the Paw Paw and bloom up the tree. I built up a bed around and extending away from the Paw Paw to give it plenty of soil to send roots to.

There is a 50+ yr old H.P. climbing/ spreading across an 10 ft high stone wall at an old home I know. It is in full sun all day with a gravel mulch and I doubt they need to water it as it is of course quite established now. When it blooms it is spectacular. Give it plenty of water as long as its draining away and then you just have to give it time.

Thanks for the tip on triple phosphate - I will use that!