Control of insect pests starts with identification and then learning something about the life cycle since control is often easiest if you can disrupt part of that life. For example using some of the disease spores early in the life of some larva disrupts the larvas life. Dormant oil sprays smother the eggs of some insects. What to use depends on what you have.
For mosquitoes, eliminating standing water is one good method of control, although sometimes that is not possible so then either larva eating fish can be used or mosquito dunks (Bacillus thuringiensis - Iraelensis, BTI) can be used as can garlic oil floated on the water surface. But mosquitoes travel a fair distance and the wind helps, so even control measures you take may not keep them totally away.
If you purchase any commercial product dilution instructions will be on the label. You can make your own Insecticidal soap by mixing 1 teaspoon of a real soap (Ivory, Fels Naptha, Dr. Bronners, most any castile soap, many hand made soaps) in 1 quart of water. Any pest control product you use should be used with due care because all potentially can harm the good insects as well as the pests.

mcaren, if the mosquitoes are breeding on your property, and it sounds as if they are, then you should take steps to remove breeding sites. Stagnant water, very little of it, is all that is needed. If they are coming in from somewhere else, then you are limited to products that will keep away flying insects. Truthfully, I cannot think of any "organic" solution to this. Mosquito invasions usually occur during specific hours - twilight time - and you can avoid being in their way by staying indoors during this period. Citronella oil (not the citronella plant) might qualify as an organic repellant applied to the skin. My only justification for saying this is that it was extensively used by surveyors, prospectors etc. in an environment plagued by mosquito borne diseases. I have used it for this purpose and..... for many years, as a "perfume" additive to petroleum jelly as a "hair dressing". The fact that I might be the only person who is grey and bald may have nothing to do with this, of course.

mcaren,

You need cedar for an insect repellent that is almost as good as deet, not quite. There are different brands. Green Light's Lotion works well, is pleasant, non greasy.

http://www.greenlightco.com/purchase.htm

rangier (isn't connected with Green Light)

Thank you all for your advice (sorry for the late thank-you -- have been having intermittent computer problems). I wish the prevention part were that easy -- we live in Va. Beach and our property is on the Lynnhaven River -- fairly brackish shallow muddy and probably mosquito nirvana. Our property has a "dog leg" strip that goes down to the water, but we haven't cleared it yet (and legally I'm not sure how we'll wind up doing that -- harsh restrictions because they're trying to revive historical oyster beds). That area is full of marsh grasses, poison ivy and lots of muddy puddle areas. The perimeter of the rest of our rectangular lot is fairly heavily covered in trees, azaleas, ivy, etc. -- lots of hiding places. We're working to clear it somewhat (replacing ivy with mulch) but I also am torn -- I like providing habitat for wildlife (and we have plenty!).

I think the biggest problem are the Asian tiger mosquitoes. They're out all day and are so small and fast -- and from what I've read can breed in 1/4" of water very quickly. We purchased one of those pheromone/CO2 traps (is supposed to lure them in where they're fanned into a tray of soapy water) and caught lots of moths. I called the manufacturer in New Zealand and was told that "oh -- they'll work on pretty much all mosquitoes except Asian tiger mosquitoes."

We've also got what I'd consider a healthy predatory population -- tons of skinks, snakes, frogs, every bug imaginable (some have got to be predatory, right?) -- I know we've got wheel bugs because I accidentally killed a nymph yesterday before I realized it wasn't a squash bug nymph (similar body shape; wrong color...). Spiders everywhere. We live on a secluded private lane and I've never noticed the city spraying back here.

But,.... we're getting eaten alive. Even my husband and kids are getting bitten this year, which is rare. Contrary to what I've heard on the news from "studies" I would disagree that concentrations above 15-20% deet are no more effective than the lower ones. If I wear the "regular" lower concentrations I might as well wear "here's dinner" signs. When I wear the 10-hour yucky oily stuff that's 95% deet it works like a charm. It's horrible, and who knows what it's doing to me, but at least I can step outside and check the garden.

But, I did get in my shipment of essential oils -- I just still don't know how to mix the concoctions -- I've read the recipes posted but don't know what the base is. I'm even growing lots of catnip -- I don't yet have enough to take handfuls of the stuff and rub it on myself, but I'm working on it!

So thanks again -- and I'll still welcome any recipes! mcaren

We have some bad misquito years and I do not like deet and the like rubbed into my skin either. Even though it is usually warm and humid during the bad times I learned from a fellow to spray light weight, loose fitting, long sleeve and pants, then put them on to go out. Spraying a handerchief then draping over the head under a hat for protection there.
I hope there is a good recipe posted. This drought won't last forever. I hope.

Am not sure if the critters enjoying my blood when I lived in MD were 'tigers' or not. I have always been a major mosquito magnet....as well as deerflies and gnats!

The best deterrent for me was a combo of daily 200mg of Vit B-1, (or consumption of 1 tablespoon of food yeast over a vinegar-oil salad daily), plus slathering on artificial vanilla over exposed skin. Do not use real vanilla as it is 'sticky.' On the other hand, there may be some toxicity to artificial! (though tons are used in commercial foods). Of course, I'd follow the advice of others with the max coverage of body surfaces.

When I'd mow grass, I'd also pin a sheet of 'Bounce' fabric softener to my hat brim-as it kept even gnats from nibbling on me. A dairyman said this kept his crew bug free.

Have also read that folks who use the blue plastic cup with stickum to catch deerflies often get a few mosquitos embedded-am not sure of the variety. Might check that out as well-research done in NH, or another northeast state.
cella jane

I roll a bandanna to tie as a headband, and before tying it on I put several--or more--drops of Deet on it. I wear it like a sweatband, around my forehead. It keeps off skeeters & those awful little midgies.
The Deet stains the bandanna, so I have one used just for this.
Also, try using Mosquito Dunks; these are round donut things impregnated with Bt--you put them in birdbaths, watering cans etc--anywhere you want to fake the skeeters into laying eggs. The Bt kills the young & you have caused the adults to "waste" their chance at reproduction. It's a bacterium specific to insects & won't kill any beneficial insects if you leave it in your "egg laying traps."