Alum powder is typically found in the spice department of supermarkets, as well as most garden centers. But what exactly is it and how is it employed in gardens? You can learn more about alum uses in
Peak Alum Works – Ravenscar, England - Atlas Obscura
3 Ways to Grow Alum Crystals - wikiHow
The Best Way to Grow Alum Crystals at Home - Crystalverse
How to Grow a Big Alum Crystal
I grew some really cool alum crystals at home. Hope you like it! : r/somethingimade
Method of casting off the evil-eye using Alum and How to get rid of negative energy - Sanatan Sanstha
Native Plants for Southern California Pollinators - FineGardening
5 ALUM POWDER HACKS FOR YOUR GARDEN TO BOOST FLOWERING & KEEP PESTS AWAY – GKVKs – Gardening Tips and Store
Alumroot; Coral Bells - Grow Native!
California Native Gardens! - Torrance Recycles
Flower Therapy: Easy Garden Flower Arrangement and Method – Home is Where the Boat Is