Hydrangea pruning help

_MH_

Hi everyone,

I hope this isn't a silly question - We have some (too) large, mature, woody hydrangeas (both mophead and lacecap) that we cut down low a year ago - this meant we got no flowers last year but lots of (also tall) fresh growth - as expected.  My question is: when I prune down to a bud in the coming month or so, how many buds can I go down and still get flowers this year?

Thanks
Mike

Obelixx

They flower on the previous season's wood so this year, rather than shortening all the stems and risking no flowers again I would, instead, prune out some complete stems.  Select the thinnest, weakest and any damaged stems and take them out to the base, removing up to a third of all the stems.   Then give them a generous dollop of good fertiliser.

You should then get flowers on the remaining stems and a hole set of new stems which will be ready to flower in 2021.  Then, next spring, remove another third of the stems that choosing the weakest and any damaged or crossing stems.  Then remove the old flower heads from the remaining stems and feed them again.

This system will keep your hydrangeas renewed every 3 years and thus maintain flowering vigour without letting the shrubs get too big and bulky and they will benefit from increased air flow and light to lower leaves and stems.

_MH_

Many thanks Obelixx - does this mean we shouldn't even touch the new stems that have come up from the woody stems we cut back hard last year?  I was under the impression I should cut back to a bud?

Also as an aside, I think every question I've asked on this forum, you've provided an insightful and helpful answer to so I'd just like to thank you personally for being such a trove of information and a great community member.  Something for me to aspire to.

Mike

Lyn

I take mine down to about the 3 rd bud down someone’s 4th if they’re big buds, or else they’ll be huge again by the end of the year. 

Fairygirl

I'd say the advice from both these esteemed ladies is valid @_MH_, so you might want to experiment a little if you have plenty of them. 

As is often the case, your own climate/conditions will dictate the timing of pruning back to buds. @Obelixx's method is less reliant on weather though. 
There's a house near me with a hydrangea at the gate. Every year it's hacked back as you've done with yours. I often wonder if the residents think to themselves 'why does that thing never flower?' 

Obelixx

Thank you @_MH_.   I have recently moved to the Vendée which has mild winters compared to my last garden in central, rural Belgium where no lace cap or mop heads survived the winter frosts and never flowered as all they had was new wood.  Paniculata types did OK as they flower on new wood.

In this garden we have inherited two large, desne, over-crowded mop head types and I have been doing the pruning as described above and it's working.  Lots of healthy new stems and plenty of flowers and the sparrows have conferences in there.