It will bolt much more rapidly in summer conditions, but its hard to say exactly how long, because growing conditions have such an influence. I guess the best way to explain it is to say that, the more stressed the plants are factors such as heat or drought, the faster they will bolt.

Shade in the afternoon would definitely help to delay bolting. Shaded cilantro also is, IMHO, somewhat better for certain culinary uses, because it has very tender stems.

Sounds like you're doing this for commercial purposes -- you may want to check out a few of the improved varieties such as 'Santo', "Leisure", or "Slow Bolt" which were bred to be slower to bolt.

Thanks so much. That really helped a lot. I will check those varieties out.

Thanks for the tips.

I've never had much luck with cilantro in the summer. It can bolt before it grows very much at this time of year. It lasts a lot longer in the fall or early spring.

Nobody has much luck with it in the summer, not even us Northern gardeners. Though we do have a much longer season for cilantro than others in warmer zones. You can plant for fall harvests maybe mid-august or so.

FataMorgana

Thanks for that info FataMorganna!!

I planted some seeds a few days ago so I am right on time :)

For those in the south the best time is for fall and winter plantings of cilantro. Also for us in the Houston area I have gone to "Hong Kong" grocery store but that was years ago and planted a large row over 30 feet long and ended up with plants over 3 foot tall over a foot wide and I ended up giving most of it to family and friends, it was wonderful in looks and flavor, the prettiest plants I have even seen. They bolt quickly here in our weather once it starts to warm up. They can take a good frost without missing a beat.

I'm sure our ideas of "winter" and "frosts" are quite different. ;)

Cilantro - Light frosts, yes. Killing or heavy frosts, no. Most things give up for the season or for good at that point. Young plants can overwinter under the snow but do not expect anything out of them come spring. Best to sow new seed.

FataMorgana