How are you cooking and what do you plan on cooking? By cooking outside do you mean over a grill or do you mean herbs to add to a fire to infuse the smoke with the flavor. For the first anything you would use inside. For the second rosemary, sage, thyme.

Ditto Maifleur. But I'd add something lemon-y, like lemon-scented geranium, or lemon balm. Aside from the delicious flavour and smell, lemon-scented herbs tend to help keep down the mosquito population. Handy if you're entertaining in the evenings. Mint is also useful.

Yes, for grilling and infusing flavor is a good idea. I have never tried useing herbs for grilling. When you use herbs for infusing flavor, do you just cut part of the plant and throw it in the fire or does it have to be dried?
thanks

You use the fresh plant. Similar to using soaked wood chips I find that if you allow the herbs to soak in water the herbs absorb the water and smoke more. You can throw directly on the fire but it may be better for your taste to place the herbs on low coals or a chip basket at the side or end of your grill so that the smoke forms slowly and lasts longer. Throwing directly depending on the herb can cause a sharper flavor that some find distasteful. In several cultures the herbs are tied in bundles and then dipped in an oil vinegar marinade and brushed on the grilled items. Thyme and sage stems will make a good brush after removing leaves for another use.

You can of course prepare a paste of chopped mashed herbs and butter and apply the paste to whatever you are grilling allowing it to melt either fully or partially before removing from the grill. These herb butters can be used all year.

The thing with using herbs is to try different combinations. Just because one book states to use a specific herb with a specific food you do not have to follow that advise. Crush the herb in your fingers and think of the last time you had the dish you are about to make. In your mind do the memory and scent go together or clash.

In grilling and other cooking you will notice different tastes and scents depending on when the herb is added. Generally, but not always, a herb added at the start of cooking will have a mellower flavor than one added at the last minute.

Remember to use vegetables in grilling. A local grocery has the most wonderful grilled articoke? They tell us they are grilled and then steamed but we have not been able to decide which herbs are used.

Bay is good both for marinading and burning.

I like to use branches of rosemary for basting when grilling,even as a brush for barbecueing. As the herb is heated and the marinade, sauce etc. gets warmer, the herbs flavor is added to the grilled item. Try using a rosemary brush with an olive oil and garlic marinade ( with whatever your favorite herb is) and use it on grilled veggies. We love zucchini done this way