You know those shaped-plastic blister packages that a lot of products are sold in, filling up your plastic waste bin? Here's an easy way to (partly) reuse them if you have a vegetable garden! All you need is scissors and some way to label things.
A lot of this style of packaging has large rectangular flat areas of plastic; almost always on the back of the package, sometimes areas on the front too. Find all of them and cut them out, so you're left with a stack of flat, rectangular(-ish) pieces of plastic.
Then just cut those rectangles into strips of about 5-10cm. They don't need to be cut nicely, they just serve as posts for your labels! Then either print labels and stick them on or, alternatively, write on them with a thin permanent marker.
Now you have tags for your plants, without needing to buy a bunch of new plastic ones!