No, we’re not talking about the fancy metal kind in botanic gardens. Save the plastic ones that came with any sets purchased from a nursery. Tape these to a page for future reference. Also save any plant care notes that come with online orders
Seed Packets. Don’t throw away empty seed packets after planting. Staple them onto a page in your diary.
Observations. Make quick notes when you can about matters such as how particular plants are faring in their current location, color combinations that look good and which ones are attracting bees, hummers and butterflies.