Since it is centered around new growth, check under the leaves for thrips. They prefer to hide under new growth tips and feeding damage causes leaf-curl/distortion as they unfold.
Older leaves naturally yellow and fall away.

Vera

Here is a link that might be useful: Thrips

This is weird. The last time I looked at this thread there was another post saying that your Basil looked fine but suggested that wind was possibly the problem for the curling.

I too posted that your Basil looked fine along with a pic. of my basil, but now both posts are gone! Second post this week to disappear on me.

Phht! Computers! Go figure.

But your Basil looks fine. Mine does the same thing and they're quite healty. No bugs or diseases or anything.

Best Wishes
Amino-X

I think the posts may be missing because GW has been having some technical issues lately..
I may have jumped the gun on this because besides the leaf curl damage caused by thrips, they also leave little brown strips/spots from rasping the leaf surface with their mouthparts....a small amount of the pests on a plant may not show this for a while, but the population explodes rapidly. We see thrips everyday in the greenhouse, but plants are usually treated before the rasping damage, but not before the leaf curling or they are spotted on sticky cards first placed near a crop. For example I got them on my peppers and tomato crops, as did many other student crops, but all where treated before signs of visable brown spotting/striping....BTW I'm graduating this month! Wooohoooo!!!
Very strange my basil never looks like this in the garden and it's windy where I live. On a day the wind don't blow you notice LOL!

Vera

Thanks Vera and Amino X. My basil tastes and smells okay and other than the crinkled leaves, seems to be growing well so I guess I wont worry so much. I didnt see any thrips on my basil or any damage that looked like thrips. But I did have thrips last year on my petunias. Neem oil seemed to work well, but this year has been so hot I am afraid to use anything oil based. I am not a morning person and cant seem to get going early enough to spray before it gets too hot. This year we basically had no winter so I am seeing a lot of pests that I didnt have last year. I am going to try spinosaid since it doesnt need to be applied as often as neem or insecticidal soap.

Thanks!
Lydia

PS. I did notice a lot of problems accessing this site this weekend, Hope they got everything fixed.

I'm having the curly leaves problem too. :S
It usually appeared on the top few leaves which i'd clip off. Hmm... I'm thinking that maybe it was rain/dew that causes those curls/dimples because it had been rainy and had little sun lately... but that's just my guess. I'm still trying to google it out.
Scientifically, (I am not a science person, but I've read about it in school last time) leaves goes pale when they don't have enough sun light. So... perhaps you could move your plant somewhere with more sun light?

Cheers.

Here is a link that might be useful: zu

I stumbled across this because my basil leaves started turning wrinkly too! It's only the new growth. Not only are they wrinkly & curly, they are thinner/narrower than the usual leaves.

Anyone managed to uncover more possible explanations? Do your basils eventually get past this phase?

I am in sunny Singapore by the way... And it has been raining a bit more than usual this week or so...

I'd suggest nitrogen rich all purpose fertilizer.

Wrinkling in itself is normal.