Floppy Blackberry

[fishpond]

Oregon Thornless Blackberry
planted this last winter in a prepared hole.
Taken as a rooted cutting from an existing plant.
Watered at least once a week.
Fed once a fortnight.
Was doing well, still looks healthy.
Noticed the tip had flopped yesterday during the day.(watered and fed last evening just to be sure)
It was erect last night.
It has flopped again today.
It is in full sun, when we get it.
Nothing else appears to be affected, Even the mother plant and 1 other offspring in the shade.
Any jokes about V***** and e******* d********** will be laughed at
I wonder if it the roots that haven't established themselves yet.
Any thoughts?

[WendyC]

I think if it is only droopy in the heat of the day, and then recovers there's nothing much to worry about, especially as you suspect the roots haven't extended that far yet. You could try a mulch to help conserve water and keep the roots cool.
You say you prepared a hole for planting, but what is the soil like around the hole. I reason I ask is that if you have planted it in nice compost and the rest of the soil is hard work, the roots may be unwilling to leave their hole to search for water further afield. Would you swap a duvet for sacking? I'd be surprised if it needs watering and feeding quite so often. Lay off those a bit and the roots might venture further.
Interesting leaves by the way. Quite different from those of "Loch Ness".