A month to grow sugar crystals.

 Tighe and I watched this video on how to make sugar crystals in geodes by Ann Reardon
https://www.howtocookthat.net/public_html/rock-candy-geodes-recipe/

 After a few days, our crystals were tiny, so we wrapped them up in foil, and left them for another week.

 They were still tiny, so we left them for another week.

 After a month, the crystals were a decent size.  This was fun to do.