Unlike mint, Basil grows best in full sun. Why dont you find a sunny spot for it? Probably getting plant would be more suitable for you. Plant them about a foot apart and try planting basil seeds between them. This way your childeren will see how a plant grows from seed. With your basil, let it grow about10 inches then cut from top of each branch roughly 3-4 inches, just about a quarter of inch above where two leaves are accross each other. In a few days two branche will grow above each of those leaves. Again, let those branches grow about 10 inches and repeat the process. Given you have a good growing condition, your basil will have many branches. You dont just pick the leave off of basil. If the seeds that you planted germinate, you have to thin them. lets say only have one or two of them between your previously planted basils. The seed package should give you some guideline. But try to find a sunny spot. Probably cilantro grow better where you have described. I see you are in zone 5. Probably you will have to wait til the end of May?? or after mothers day??to plant basil. You have to know when in your area the danger of frost is over. Basil will not grow if it is cold and a light freez can kill it. But you can plant cilantro , both plant and seeds in your garden, RIGHT NOW, TOMORROW.

That sure looks like insect damage to me ... the mint won't do much to the basil (except try to take over the world!). From the pattern, I'd guess four lined plant bugs or maybe a leaf miner but you'd have to go out and check the leaves to see what critters are running around. If it's four lined plant bugs, then the basil should just outgrow the damage. Slugs or Japanese Beetles would eat more of the leaves.

Thanks everybody for the feedback. carolb_w_fl I saw that mildew photo and my leaves aren't fuzzy, just dying on those brown spotted areas. I also haven't been spraying anything - and no changes to the soil or how I water them. coorscat, I was thinking it might be something like that. It's affecting most of my plant (the genovese one, though not as bad on the other basil types) so if I pick off the bad leaves I'll lose all the leaves. I may try to cut it all the way back to see if it will make a comeback though. I did a little more research and it looks like it might but fusarium wilt or late blight, both of which are a bummer. Anyway, if anybody has any more ideas of how to treat it/avoid it, I'll take suggestions!

Leafhoppers. You can see what they look like in this other thread that was just posted: http://forums.gardenweb.com/discussions/3931438/insects-on-my-herbs-please-help