Paint that will work in outdoor applications.
Dye an outdoor rug.
I have dyed a lot of clothes but never a rug.
Outdoor spray paint i recommend rust oleum painters touch i used about 3 5 cans for my rug but it will depend on your rug and the design you choose note.
Just prior to dyeing add several large potfuls of boiling water which will give your rug a much better color result.
After a few months of having the rug outside i would not recommend the fluorescent rust oleum paint shown in the middle of the photo below.
Stir the dye bath with a wooden stirring stick to evenly spread the dye.
Using a spray bottle is an interesting idea for applying dye to large items.
I took the rug outside laid it on an old shower curtain dissolved the dye and put it into an empty windex container.
The more synthetic in the fabric the less dye it will absorb.
You can keep your color fresh by setting it with a vinegar and salt solution both during and after the dying.
Practice the different colors on a piece of white paper until you are able to match the color of your indoor outdoor carpet.
Different carpet dye sticks can be used together to blend into different shades and colors.
Different fabrics do absorb the dye differently.
Then i sprayed the dye all over the rug until the color was fairly even.
You might also want to test the dye on a small area of carpet which isn t normally visible.
Mine is an ozite 6 x 8 rug in bark it cost 12 bucks and i had a 2 dollar rebate.
If this size is too big you can cut them down with a scissors to any size or shape you desire probably even puzzle pieces.