Bazza wrote:
I am refashioning the garden this winter and have bought several potted
roses for a new bed, I have access to free composted stable manure at
least for the next couple of weeks.
Is it beneficial to place this in the bottom of the hole when planting
the roses or would this be detrimental to them?

Bazza

Composted stable manure-and for free? You're a lucky man Bazza.
Just one or two comments (just in case )
Don't plant them where you had roses previously.You will not get
the best results.
Shake out the loose soil about the roots especially if it is peat based.
This type of soil will act like a wick and dry out the roots.Roses do
best on heavy soil.
Dig a good sized hole and incorporate the manure in the bottom
and the spoil.
Firm it all down after planting.
Add a sprinkling of sulphate of potash and lightly hoe it in.This is
a winter dressing which you should give every year at this time,
because it's now that next year's buds are being formed in embryo,
the number of petals and the colour.It's too late in the summer when
the flowering starts.
You can still give them some in the summer to keep them going
into the autumn.
Roses can mean work, but they are without equal.
Happy gardening!
Sam