Thanks Rob and Elsie
Will try and explain Flora, the BG in the original is fairly irrelevant something neutral, a light grey will do.
It's then just a straight shot of the dandelion processed in Capture one but only concentrating on the dandelion.
imported it into PS then I added a textured BG to it, you are not replacing the BG just adding to it and brushing out the bits you don't want
there where two layers at different opacities, the colourful layer at about 40% was erased using the clear brush on the flower at 100%
and the textured layer at about 5% was erased with the clear brush at 50%
When you are happy flatten the image and save.
Thats as clear as mud isn't it.
So Tim any lens would work I don't know what lenses you have, anything you can get fairly close will work the 55-200 would work I think or maybe the 18-55.
I used the Fuji 60mm macro which isn't really a macro but for close up work like this I find it to be perfect, its a bit slow to focus sometimes but I'm not exactly in a hurry.
I picked it up for £180 on eBay it would do decent portraits too but maybe not in a cosplay convention as I think it would take a while at times to focus in the light available.
If you can get one cheap enough it's a handy lens to own.