Make Chamomile Tea, cool and water top of soil with the tea.

Also, air circulation is important. You might try having a small fan running near your seedlings next time.

Use the minimum amount of water and always water from below.

I don't think I'd recommend that those jiffy pellets be watered from below. Here's my thinking:

These pellets are made of 100% peat moss, very finely processed. Oxygen will be at something of a premium in such a mix. Seeds, seedlings, and growing plants require plenty of oxygen (and gas exchange) at the roots in order for rapid cell division to occur. Oxygen in and CO2 out. Watering from above accomplishes this every time you water.

However, using those pellets can be a challenge in the first place. I'd be sure to provide good air circulation, absolutely! Next time you may want to think about using small pots and a fast draining potting mix.

I've seen lots of recommendations about the chamomile. Powdered cinnamon, too....sprinkled on the top of the soil. I've not had reason to try either of them, but would certainly give it a shot.

I've had good luck wintersowing them outside in milk jugs. This method pretty much eliminates damp off problems. Check out the wintersowing forum for more info.

Lavender from seed is notoriously difficult. Its my understanding that Lavender is typically propagated by cuttings. Thats always worked really well for me. I dip the cutting in rooting powder before I pot it up. Check out the propagation forum and maybe you'll get some other tips.

Good Luck,
Little John