Help with Herbs, please?

I’ve got a reasonably good herb garden, but there is one thing that just won’t grow for me…….coriander!!!

What is the secret?

I live on the Gold Coast in Qld, Australia in a tropical climate, but cold at night time in Winter. I don’t over water or give too much sun or shade, but the plant will never last longer than, say, 2 weeks without going droopy and eventually fading away.

Any coriander experts out there, please give me yout secret!!

Thanks

Since it is a mediterranean native, you’d think it would thrive in your location!
From e-How, the only thing I can think of, is:
"Choose a site that gets full sun. Like most herbs, coriander isn’t fussy about pH, but it needs soil that’s well-drained and amended with plenty of compost.

"Plant coriander where you want it to grow; it quickly develops a deep taproot that doesn’t respond well to transplanting."

So is it in full sun? Are you growing it from seed, or trying to transplant?
Also, "Keep a close eye on young plants to make sure they don’t dry out, but once established, coriander (Mediterranean native that it is) needs little water."

Try it again! lol…and enjoy your herb garden. Sounds wonderful.