Just can't resist that little 80s reference.
Ghosting is a term, probably borrowed from screen printing, that we eco printers use to refer to the marks made when pigment from the original dye source bleeds through into contacting layers of fabric or paper, usually because nothing is present to stop it. It can be a maddeningly unintentional effect but equally it can be an intentional technique. Some eco-dyers in search of crispy prints will go ballistic when it happens unplanned, some embrace the happy accidental serendipity. I tend to fall into the later group, accepting that mama earth dictates the design. I mean, just look at this image of a ghosted eucalyptus leaf on cochineal dyed silk!

But if I'm honest sometimes I do want clearly defined leaf prints, so how to create a barrier between layers that remains true to the natural process? Using plastic feels like a betrayal to the integrity of what it means to be 'eco'. What can be more unfriendly to the environment than plastic? Especially that evil single use plastic food wrap, and sorry if you use it but I am not an advocate. I'm with India on this.
Here;s a creative solution. When we moved house I scored, amongst some packaging, a roll of recycled unbleached cartridge which is handily the perfect width to match my blank silk scarves. Following the Michael de Meng philosophy of *inherent thingyness, I tried placing this paper inside my tightly wrapped bundles between layers of silk and leaves, and bingo! It's like mama earth gave me a bonus. The results were both delightful prints and textures and a useful source of art material. Paper is relatively effective as a ghost buster, even more so when combined with another thin layer of fabric. It prints beautifully but surprisingly the marks don't always mirror that on the fabric, they seem to have a life force of their own. God knows what I'll do when this roll runs out!
"....and if you want clear leaf prints, put recycled paper between the layers. you'll have the bonus of making something gorgeous to write on" India Flint

I use it to make packaging for scarves, for hand made books, for wrapping paper and gifting to others. It's not the perfect solution to avoiding ghosting, and certainly not the only one. And you'll find if you experiment, that different types of paper, or dye stuffs, or techniques will have different results. But as a natural dyer you'll already be familiar with the endless variances we deal with anyways. However, sustainably sourced paper is a better alternative than plastic by a gazillion miles in my opinion. Have a go, see what you discover. Green it up.

* Inherent thingyness - Looking at objects and seeing what about them will assist in the assemblage process.