Gabion planters?

Has anyone ever used gabion planters / raised beds?

I’m considering doing a border of natives but worried the 20cm high and 100cm depth won’t be enough. I’ll dig and refresh the soil below a fair bit so the 20cm may not be so much of an issue, but unsure about the depth, the inner dimension will be just over 80cm deep by 480cm wide.

Hoping to plant some things that are 1.5m – 2m high. Grevillea, banksia, Gerald ton wax.

Thanks in advance!