What can I use as filler in planters?

I use colored sand from the dollar store.

What a fabulous planter! I think you'll want to fill the bottom with stones - any stones will do - even free ones from outside your home. Then potting soil over that.

I love pine cones for that kind of application because they're so light!

Chopped up packing peanuts.

Any kind of styrofoam should work.

The plastic foam peanuts that cushion mailed products can be used as lightweight filler for a planter box, but don’t pour loose plastic foam peanuts in the planter. Instead, put them in plastic bags, and fill the bottom of the planter box with the bags. Otherwise, plant roots will grow into the peanuts, creating a mess when you want to switch plants. Blocks of foam also can be used as filler. The foam blocks don’t need to be bagged if they are large, but cover them with a piece of landscape fabric to keep soil from washing between the blocks and downward in the planter box.

here is a light weight rock for your succuelents

https://www.google.com/aclk?sa=L&ai=DChcSEwjY1LvIzZDoAhUm_-MHHai8BtcYABAVGgJ5bQ&sig=AOD64_0hvejsp9w_P7l23h9oyCxXwpJIsw&ctype=5&q=&ved=2ahUKEwib-LHIzZDoAhUHLK0KHTTuD0oQ9aACegUICxCNAQ&adurl=

You can use just a small layer of stones at the bottom to help with drainage and fill the rest with dirt.

Styrofoam peanuts work well. I usually place them in a ziploc bag so they don't get mixed in with the dirt should I change out plants. There will still be ample drainage under the bag.

Styrofoam, you can get the green floral kind at Dollar Tree.

Hi ! Try putting in floral foam . It is super light weight and easy to cut , to fit into the space . I would still like the bottom with a thin layer of pebbles for drainage , first .

then lay your diet over the foam and plant as normal .

My question, is there drainage? I would begin there and hope there is...before proceeding with anything else.

Depending on how deep it is, you could use materials you have in your recycling and trash like water bottles or egg cartons.

What a fun project! I've used sand as a filler with my succulents, along with stones. Enjoy your project! Hugs, Holly

The best environmentally friendly answer here that's "lightweight" as you asked for and you won't have to worry about weight, plant roots, drainage and so on are the pine cones!!

Slices or pieces of styrofoam from packing materials in shipped items. Often the packing is an odd size and foamed to protect the item purchased. Save these pieces to upcycle and use in large or small planters or as a base for a flower arranement as filler or a base.

That looks like the perfect size for succulents!

You can use small pebbles the a little sphagnum moss and then the succulents.

Hi, Polystyrene bead!

Moss - soak in water and then ring out and use some glue to hold in place.

My trick, for a light weight option that looks like soil is to: cut up floral foam into chunks or styrofoam and put them into little black doggie poop bags 🐶💩 ~ new, unused ones of course!! Tie it up and now you have a dark, lightweight base that is also contained. You can poke some holes into the bags for water drainage. Then add a little moss or small rocks etc. on top.

small layer of plaster of paris will add weight to it.

use some fish tank gravel or other small pebbly gravel in the bottom 1/3 of it

I would use moss