Lost,
I agree with the others, cover it. If you have a sunbrella (canvas) sailcover it will protect it from UV but still allow the sail to slowly dry. If the sail is relatively clean, mould and mildew will not be a big problem.
Stu,
I was born in the PNW, and just because I go through WD40 and/or other lubricants by the case lot does not mean it rains here alot

. Once I spend a whole weekend removing the "green stuff" from the boat in the spring, (once the dock water is back on), the boat looks good again. Around here, if I stood outside all fall, winter, and early spring, without taking a shower or bath, I would be pretty rusty and covered with mould too!!

Besides, at least up here, we know about any deck or fitting leaks in a hurry

Regards,
Tom