I've been trying to grow dill and coriander in the garden several times. No joy. It's too hot and too bright, and the herbs bolt and go to seed almost instantly. This got me to thinking that, if I keep the temperature to something reasonable and the light somewhat lower, I might have better luck. Keeping things a little cooler is easy, just move them inside. But the light is difficult there. Sun coming in through the windows is what you don't want to have in a Queensland summer, and the house is designed to minimise sunlight in summer and maximise it in winter.
This is (hopefully) the answer.
That's an iDOO hydroponics system with a 4 l tank. I picked it up during one of the limited-time sales on Amazon at half price. Left to right columns, I seeded watercress, coriander, dill, and mustard greens. First sign of life from the mustard on day 3:
On day 12, things are happening already. Two of the coriander pods did not germinate, so I re-seeded those.
Four weeks since I first turned it on, and I've been munching on fresh mustard greens for more than a week. The dill is coming along nicely, and the coriander is not far behind. Next time, I'll probably give the watercress and mustard a miss; those are so easy to grow in the garden that there is no need to put them into the hydroponics system. Instead, I'll probably have half dill, half coriander, and stagger the seeding so there is always some supply.