Forbid and Floramite are both excellent miticides and they are fairly mite specific so they don't kill everything. I just handpick snails and slugs off my plants.
Karyn

ok thanks. I'll get some. I would hand pick the snails, but I never get to see them, It seems they do the damage over night.

I use diatomaceous earth for slug and snail control for many of my plants but passies are too long and sprawling for it to be of much help. If you can spread a ring of DE around your plant that might help because they won't cross it but they can probably find another way to get on the plant. I've also heard of people using copper strips to keep slugs and snails away. They supposedly won't cross that either. The problem with DE is that it needs to be reapplied after it rains so like I said earlier I pick them off by hand. Your neighbors might wonder what you're doing in the yard with a bucket of soapy water and a flashlight late at night. LOL

Forbid and Floramite are pretty expensive and you use very little at a time but they are both very effective. If you have any gardening friends that also have a mite problem you might want to see if you can get someone to go in on it with you. They both run about $350.
Karyn

Wow that is expensive!!! I'll have to see my options because money definitely weighs in my options. Ebay has a 1 oz bottle of floramite for $22, so maybe that is the way to go. I have to think fast because they are taking over. Thanks for your help Karyn!

1 oz of floramite should be enough. You only use 1/4 teas for a gallon of water. I only mix up a quart at a time. It contains an ovicide so it will kill the eggs as well as the adult mites and doesn't need to be reapplied.
Karyn

I use a granular systemic (by Bonide) to rid my plants of spidermites. (actually I just use it on Incense and all the mites go after that one first, of the ten passies I have). I generally give my 5 gal Incense 1 tbs sprinkled on the soil (under mulch) when I take the plants inside, and then again a month later.

This has solved my mite and bug problem for the past 3 years. At this rate I'll have enough systemic for 20 years (or so) with the one 8 oz granular bottle I bought

~Chills

keep your eyes open for caterpillars, there are a specific type that feed on passifloras here in FL, kind of orange with black spines, finding them when they are big is easy, not so much when they are real small. Not ever really seen slugs and snails attacking them that much here

You are thinking of the Gulf Fritillary. It would be a shame to kill them. They turn into such beautiful butterflies.

Yes Karyn is right, they are Gulf Fritillary butterflies. Yes I have had some plants eaten up by them. I usually pick the cats off untill my plant is big enough to sustain them without getting devoured. I get plenty of Zebra butterflies too, and I love those.
The vines that are in my porch definitely have a snail and spider mite problem. I have gotten these pests under control for now though.

You might try Spinosad for spider mites. It's a fairly new product and I only have limited experience with it. but it seems to work very well.

Here is a link that might be useful: Spinosad info

I was wondering if anyone here has tried using diatomaceous earth in spray form for the demon spider mite. Living in so. Cal. the intense summer heat makes most forms of organic control impossible. Spinosad was hopeful, but has turned out to be of little use against them. Still looking for something that works!

I've never heard of DE in a spray form.

and why would you want to use DE on mites to begin with?
DE is like razor blades to snails and slugs. Not gonna help with walkers. If you are extremely vigilant you can hose a plant down, every surface and wash them off, especially the larvae. Do it daily. You results may vary but it will help. Neem oil could gum them up, but don't suffocate the plant. Combination attack is best.