There's all kinds of growing medium - Perlite, expanded clay pellets, rock wool, and coco coire are probably the most popular. Pretty much any inert substance you can think of can be used to grow stuff in a hydroponic system. There are advantages and disadvantages to all of them, but almost none of them are both Cheap and Available at the grocery store.
I got this pool noodle for $0.95
@frickhaditcoming Yes! They do actually grow like this. I will tell you to be careful of how tight you make it. I haven't quite found the best balance yet. The only ones that seem to survive are in that middle part where the gap is the widest.
@frickhaditcoming And this is not for starting seeds. You have to sprout seeds using some other method and transfer them to the pool noodles.
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