This is a host of random suggestions I have found on various websites....

It seems that any plant just 'sitting in a pot' isn't going to give off enough oils to repel anything. But if you had suitable plants you could run your hands through from time to time as you sit on the patio to release the oils, it might work.

Try these:
Lemon thyme
scented geranium, Pelargonium citrosum Vanieenii
lavender
tea tree
pennyroyal
lemon balm (there's a strain with high scented-oil content available)
catnip (the essential oil is 10 x more effective than deet at controlling mozzies)
horsemint
rosemary
marigolds
ageratum



And a few other ideas:

Protect natural mosquito predators such as dragonflies, ants, ground beetles, spiders, water striders, frogs and snails. Avoid spraying broad-spectrum insecticides that kill off many of these beneficial creatures.

Keep chickens, because they eat mosquitos.

Numerous studies have confirmed that electronic zappers also kill many beneficial insects and relatively few 'skeeters - unfortunately, less than 2 percent of insects killed by bug zappers are the biting female mosquitoes.

One good way to help shoo mosquitoes off your deck or patio is to use a fan. Mosquitoes may be great smellers, but they are weak fliers. If you often sit on an unscreened porch, install an overhead ceiling fan: you'll be cooler and have fewer bites.

Avoid using highly perfumed soaps and shampoos, wear loose-fitting clothing, which forms an air barrier between you and the bugs, and use an herbal repellent. The key to using any plant-based repellent is to watch how it's working. Immediately after application, mosquitoes will not light on your skin; as the effectiveness wanes, they will light but not bite. That's your signal to go inside or to apply more repellent because the third stage is near - when the mosquitoes light and bite.

In a 2002 study conducted at the University of Florida's Medical Entomology Laboratory, three plant-based repellents were found to be effective for at least an hour. These were Bite Blocker, which contains soy, coconut and geranium oils (and which now has had citric acid added and is called Bite Blocker Herbal Spray), Repel's Lemon Eucalyptus and Fite Bite Lemon Eucalyptus, both lemon eucalyptus-based lotions. (The study found citronella products, Avon Skin So Soft and wristbands laced with DEET provided protection for only 20 minutes or less.)

There's also a variety of ideas for repelling all sorts of insects here http://www.lowchensaustralia.com/health/homeremedies.htm


Then finally, a recipe for your own natural repellant:

Herbal Insect Repellent
2 1/2 teaspoons total of any combination of the following essential oils (available at health food stores): basil, cedarwood, citronella, juniper, lemon, myrrh, palmarosa, pine, rose geranium and/or rosemary
1 cup 190-proof grain alcohol (available in liquor stores)

Place ingredients in a jar with a tight-fitting lid and shake vigorously. Transfer to small bottles for storage. To use, rub a small amount on any exposed skin (test first to be sure your skin will not be adversely affected by the repellent) or dab it on clothing.

Experiment a little to find which essential oils work best with your body chemistry. If you're lucky, you also will like the way they smell; otherwise, add a few drops of peppermint oil to fine-tune the fragrance.