Sounds like those sheets are a fail, terrible performance after a short time. Try ordering the bamboo sheets from North Shore Linens next time. Mine looked ok for a year before the colour went weird. More on reddit.com

I used to have bamboo sheets and swore at one point that I'd sleep under nothing else but bamboo. However, that was years ago when the bamboo craze was just getting started and everyone thought, wrongly, that bamboo was the 'it' fabric that would not only help be more eco-friendly but also was durable and super-soft, to boot! It was as soft as satin/silk and it held up semi-well to washing without pilling/etc. So, yes, at the time I thought---wrongly---that it would not only replace all other fabrics but would help lead us into a new eco-friendly future. I was naïve as hell. To have sheets that soft for that cheap there has to be a catch. Which you might disagree that bamboo is cheap in comparison to other fabrics when you're looking at places like Cozy Earth (highly overpriced and not really any different from other bamboo bedding companies, in the end). Egyptian cotton, Supima cotton, linen, silk---all natural fabrics that are super-soft (if made right)---are pricey for a reason. They are the more eco-friendly versions (compared to bamboo, though Tencel is a better version of it, I will admit). Keep in mind that anything that says 'cotton blend' or 'microfiber' are essentially (when you do some digging) 9 times out of 10 are going to be plastic byproducts. Bamboo many times is one such fabric. When bamboo is done being doused in tons of harmful chemicals what's left over is barely considered 'bamboo' anymore and is usually created with tons of harsh chemicals added to it to melt it down to get it that soft. The OEKO-TEX and Certi-PUR certifications might test to ensure that you are not sleeping in chemicals, but recent studies on microplastics in the oceans (and the high presence of rayon/viscose included in that study) leave me a bit leery on bamboo's effect on the ecosystem, especially the conflicting reports about it---either way, until we know more about it as a fabric (after 20-30 years of study) I would be cautious about expecting a lot out of it. Personally, I would much rather use cotton/silk/linen fibers just on account of them having been around for longer and more tried-and-true fabrics to use for bedding in general. This is also not taking into account the sheer devastations that bamboo production will wrought on its surrounding areas that they farm it from, nor the leftover sludge/chemical baths that are leftover from the textile industry that they will dump back into the environment, which at least Tencel is trying to help reduce (but rayon/viscose process is pretty horrific and it does have a human cost to it when it's produced that should not be overlooked). Cotton might be a water guzzler in comparison to bamboo, but damn does it not use so many harmful chemicals in its production compared to bamboo. I would stick with 100% cotton or linen, to be honest. Or, if you want absolute silky softness, then silk would be a good way to go, though it will cost you an arm and a leg and be a pain in the ass to wash and somewhat hot if you get one that's very high momme/tightly woven. Which is why I always recommend 100% Egyptian cotton or Supima cotton for softness and durability usually. Though, keep in mind that the softer and lighter the weft of the fabric weave is the less it will last. Either way, most sheet sets will not last more than a few years anyway unless you buy absolute quality which will range in the hundreds of dollars for silk/linen/cotton fabrics. If you go the route of cotton you will be best served in the 200-400 thread count range since that's the 'sweet spot' for most people in terms of softness and longevity. If you still need more convincing about bamboo's ugly side, I'd recommend doing a deep-dive into bamboo and its production process to get a firmer idea of why it is not all it's cracked up to be for not only the environment but also the human costs in the manufacturing stage. Either way, I wish you well on your search :) P.S. 100% bamboo is basically rayon (bamboo cellulose melted down without any of bamboo's good properties left) to classify it as 'bamboo' so the set you picked out that's 40% bamboo and the rest polyester is basically still classified as a plastic mix. More on reddit.com

There’s no such thing as “bamboo” (or “eucalyptus” for that matter) clothing and bedding. What you are wearing is Rayon, and yes it’s marked up insanely over material cost because people hear “bamboo” and think “natural” and “green” and “sustainable” (all of which is complete bullshit, the manufacturing process for rayon via bamboo cellulose is INSANELY toxic and corrosive, there’s nothing green about it). A bunch of big retailers have already been sued and fined by the FTC for labeling their bedding that way, but unfortunately the FTCs ability to go after every little company making similar deceptive claims is limited, and it’s a very effective marketing strategy (as seen in this post and every other one about bamboo bedding in this sub, it makes people think a synthetic fiber is a natural fiber), so the companies all still do it. More on reddit.com

Just a side note: Tencel and Bamboo fabrics are both made from wood, softened chemically. They can feel great out of the package, but in my experience that softness goes away after a few washings. More on reddit.com