Getting that nice solid colored blurred background is all about finding the right camera angle. Most macro photographers that I have worked with in field workshops will find a subject, plop down in front of it, and shoot without ever exploring all the camera angles for the least clutter background.
Here is an image of a cluttered field with some white daisy flowers that I am going to shoot. My subject is the small white daisy just above the center of the frame. As you can see it is really cluttered all around the flower, but if you work all the camera angles, you can sometimes find a gap where the background is far enough away to get a nice solid colored blurred background.
I have shot this flower at different camera angles to show what you will get for a background if you are not paying attention. In the camera angle of the first image, you can see in the background a small flower near the bottom left corner, and stems of grass throughout the background. In this very tight cluttered surroundings you will have to shoot in the low f-stop numbers to help blur the background. I was shooting at f/3.5 with my 180mm macro lens. On all four images I placed the point of focus near the front part of the flowers yellow center area. Now at this small f/stop number and very shallow depth of field, you will not get the whole flower in focus. Under the conditions of all this close clutter and using a low f/stop number we will have to sacrifice some focus on the flower to get our nice solid blurred background if we are not using focus stacking.
In the next angle you see another flower in the background and more stems including some distracting beige colored stems that stand out and pull your eye away from the main subject.
On this third angle you are seeing the grey color of the 4X4 wood post and some more multi colored stems.
With the last image I was able to find a camera angle where there was a small opening through all the clutter with the background subjects far enough away that I could get a nice solid colored blurred background at f/3.5.
Although it is tough working in these conditions, you can still pull off a decent shot by working the camera angles.