@Autotron ..... Mulch, I use sweet barley straw - worms like it and feeds the soil, albeit not much but a lot for container mulching .... and it looks good and cover crop can get thru ....
https://buildasoil.com/products/barley-straw-mulch
feed store, they carry straw just not sure of their sources or type of straw ... I’m not an expert so I spent the $12 and got online .... more than enough for 25 or more containers and nice straw and packing, stores nice and is convenient.
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