"Outdoor Mandevilla"...what's wrong?

Hi all - I just noticed this afternoon that the stems of some of the budding flowers on my Outdoor Mandevilla seem to have died (see photo)...plus another photo of one of the leaves (I think two leaves in total were like this) -







Any ideas and/or remedies please? TIA

 

When did you buy it?

Looks like the flowers stems are rotting.

I doubt the plant has ever experienced rain.

Hardening off comes to mind.

 

• I never grown a Mandevilla but read its usually pretty easy to take care of, but it is also prone to few common diseases that can threaten the beauty of this plant. I looked onthe net and came across this site it might help . .

Tips & Information about Mandevilla - Gardening Know How
www.gardeningknowhow.com/ornamental/vines/mandevilla

 

I have many of them (some for 12 years outdoors) and never have any problems. It looks rotted as Pete says. Because of my climate they are kept drier but watered frequently. I don't know about the leaf problem. Let it dry out and see if it picks up.

 

Thank you everyone…
@pete …I did actually remember to harden this one off! Planted in it’s pot mid May. It’s only some of the stems that are rotting? Maybe I’ve watered too generously? When I bought it (from a supermarket) the label stated ‘hardy’…it was only when I did further research that I read that it’s anything but!
@Janet mahay … thanks, I’ll take a look at that site!
@Victoria … I will hold off the watering for now and watch with interest - and fingers crossed! From your reply, it sounds as though you have fabulous success with them…but are you in the UK?

 

No, I am in The Algarve, Portugal.

 

Ahhh - lucky lady!!