The Citronella plant is a wonderful mosquito repelling plant to have planted around your patio or any other area you spend time outside.
The Citronella scent that the Citronella plant gives out will repel the mosquitoes just like Citronella candles will.
Lavender plants are also another good plant to plant as well as Garlic plants to repel mosquitoes.
I always recommend if you can afford to is buy a mosquito magnet that uses propane to catch and kill mosquitoes and although they're a bit expensive they really do work and they've gotten rid of tons of mosquitoes in my yard and I'm happy I bought it and the mosquito magnet was well worth the money spent.
The mosquito Magnet sucks up the mosquitoes like a vacuum as they're attracted to it and then it kills them.