[TowerTalk] Manilla rope rejuvenate?

[wb2aio at yahoo.com]

I use 5/8" rope to haul things up, pull the extension ladder up, or with my arborist device when on my steep roof., tc. It ends up spending the summer hanging while I do my various antenna projects.  It has spent probably the last five years being outdoors for several months each summer. 
I don't see any signs of fraying or rot but was wondering if anyone has any suggestions on how I can prolong its life? Perhaps lanolin soak or? It has lost its golden color to grey at this time.
73,Kathy, w2nk