What I do depends on the herb. Cilantro does well with succession planting. Basil gets the flower buds pinched back or cut off when I am cutting leaves for use. It encourages the buds below to branch out giving me a fuller plant.

You've got two different types--cilantro is really a cool season grower and will bolt in heat regardless. Just don't plan on it in the mid of summer heat. There are some varieties that are supposed to be more bolt resistant, but once it gets warm it will bolt.

Basil depends on the variety. Some flower (Thai) much faster, and pinching/pruning will help.

Start basil indoors and do some direct sowing to have basil for most all of our Northern summers. Regular basil is so easy to come by that I suggest trying basil varieties and flavors harder to come by. Thai basil is my favorite culinary basil. Try others like lemon basil, cinnamon basil, etc. Holy basil, not a basil to cook with, makes an awesome tea.

Cilantro - plant in the spring and later summer/early fall for best harvest. Let some spring planted cilantro set seed for coriander (the seed spice) or harvest seed for planting more. Letting it self-sow is also effective.

FataMorgana