There are a few ways to add fillers, and create a flat surface inside your planters or pots... However I have found that I like this one the very best! It is the cheapest, and also works so well for any shape or size of planter (for the most part). ☺️ I add some large rocks for fillers and some weight. These planters have a lot of depth, and we’ve also had a lot of wind so I need to keep my plants in place!! 😆 Sometimes I use plastic bags, bubble wrap, floral foam, or paper for the fillers & base, but like I said, this is the best! ⭐️Shop the post in my Amazon store - link in bio!