There's lots of ways to make recycled plant markers. I'm always baffled why you can buy them in the shops. Who would pay money for rectangular bits of plastic?
I've used yogurt pots, plastic milk containers, ice cream tubs, but this time I used an old margarine tub. You'll also need some scissors and a marker pen.
Cut down the sides of the margarine tub to get lots of short plant labels suitable for plant pots. If you want longer labels suitable for the garden or allotment, you could cut down one corner of the tub, then cut horizontally. Or you could use a bigger container to start with.
When you have made lots of vertical cuts, snip all your rectangles off along the bottom.
You can use the bottom of the tub, too. Just cut it into strips.
Trim one end of your label into a point to make it easier to push it into the earth.
Make sure you write with a permanent marker. It's really annoying if the plant names when you water them.