Do I really need a new digital SLR macro camera lens

I am back after the best part of a year away with various health problems now resolved. Hoping to pick up with you fellow bloggers on my favourites list. More posts to follow on my allotment plot later.

As to the title, well no, not really except I love mosses, ferns and lichen and they do look good under the microscope so to speak and I had the chance to buy the IS (image stabilised) version which does away with a tripod for most of my work. Most smartphones and even basic digital SLR kit lenses can get close enough for most pictures with some cropping but true macro at life size of 1-1 take some beating.
Let me explain what I mean by life size, it relates to the size of the sensor in your camera, so the sensor in my full frame Canon 5D is 36 x 24mm so if I photograph an image that is 36 x 24 mm it will fill the viewfinder and the final image should not need cropping, my watch face picture gives you an impression although note that very little of the face except the sub dial is in focus at f2.8 macro lenses have very little depth of field at that aperture.
Some zoom lenses mention macro but they are usually at best half life size 1-2 or even 1-4 in some cases.

My watch face at life size note how very little except the sub dial is in focus due to the f2.8 aperture set by the camera

This Herb Robert flower would need cropping to show more of the flower since it is tiny at about 1cm in diameter

Lichen on our apple tree