It might work if you lay it on its back, remove the glass shelves and cover the whole front (which is now the top). It doesn't look big enough (floor space) to me standing as is.
I see the old style wide filing cabinets with the lift up door at thrift stores all the time. They are like 3’x7’ and about 18” deep. Silicone in a heavy shower liner to protect and add mulch. Use pvc to make a light supports over it and the cover with another shower liner