Do the pots have drainage holes? Hydrangeas love their water, but they don't want to sit in it.

Yes they have holes in the base and I also used crock before filling with compost.

Well, that latter isn't great: Master Gardeners used to recommend that some 40 years ago, but we found out that that just slows if not stops the drainage. Nowadays, we just recommend putting a piece of screen over the drainage hole before filling with compost. Also, how large is large? I have never seen a dedicated porcelain plant pot more than 25 cm by 25 cm.

Öne pot is glazed but may not be porcelain 470 dia x 400 high the other is terracotta 430 dia x 320 high. This is the first year the leaves have not been dark green. What can you suggest I do.

I think I would lift them out and check the roots for signs of grubs like vine weevil. then replant in fresh john Innes No 3 type compost.
Over feeding can cause problems so I wouldn't add any more this year.

I assume the measurements are in millimetres.

Hi there,
Not sure if you received my last reply as i had problem with signall, so here again.
I read somewhere that they do not like pots after about a year, what is your take on this ? So I will check the roots as you suggest and re pot or maybe plant out, however I am concerned on our chalky soil, what is your thoughts ?
Yes my figures are in mm, I am trying to keep modern with new money and the metric system !
KR
Barry

I garden on chalk and the 3 that I have [Annabelle, Red Disc and H petiolaris] are all happy in my alkaline soil. I did have a mob/lace cap one that was a mucky pink colour but I removed it so I could grow other things.

they are ok in pots if they are kept well watered and there is some root room for them.

Hi again Seaburngirl,
I would llike to send you photos of my Hydrangeas we discused before but can see how to. Maybe you can give me your email address then I know how to do it.

Kind regards,
Barry

you can add photos to your question on this site. there are instructions. go to the your options tab and then select add a photo. it tells you there how to add pictures and the size they need to be.