When it comes to bamboo outdoor rugs there is a level of hesitancy and rightly so. Bamboo as a raw material can withstand rains and actually heavy rains. But to date it has not been test against the rigors of the outdoors of the home. What makes an outdoor rug truly one is what it made from and that is polypropylene, this is a very durable and synthetic material. Common sense will tell that a natural material like bamboo is not as strong or durable as something that is specifically made to withstand rain, snow and other elements of the outdoors. So yes you will find bamboo rugs that are water resistant but these are more appropriate for the interior of the home.
They are great for basements and other areas of the home where mold and mildew are a concern but will you put your three hundred dollar rug outside the home and exposed to all kinds of weather? That would be a mistake in my humble opinion and yes it could very well last but for how long and for how many years? The porch might be a sensible place to place a bamboo outdoor rug but even there the wear and tear on the bamboo will become more apparent than other outdoor rugs that are specifically made for the outside of the home.
If for some reason you desire the design of bamboo then you can opt for a rug that looks like bamboo but is actually made from polypropylene. The difference will be apparent but such an option is available and some of them look pretty darn good. A bamboo rug is essentially like other rugs in the home the main differences is that they require less maintenance. I know you might see some towns and villages on TV in which people have bamboo rugs outside of the home. Well those people are not paying a whole lot of money for those rugs and secondly they replace them every so often.
If you want to put yourself in that situation then by all means go right ahead. But bamboo as a material does not bode well with moisture nor is it able to withstand the pressure and friction of boots and other heavy footwear. Bamboo is actually a gentle material but flexible material. Manufactures have however made advancement in ways that makes it more durable, this has more to do with the actually stitching rather than altering the actually bamboo. So think carefully if you see an advertisement stating outdoor bamboo rugs are available.