I have had the plant for many years. Last year it seemed weak, so I divided it. This year the plant seemed to come up strong but without any taste in the leaves. Seems odd to me.
My Tarragon Plant Has No Anise-Like Taste
Certified GKH Gardening Expert
This happens to herbs when you are too nice to them. The better their conditions, the weaker and more diluted their flavor becomes. They need to struggle a bit to have good flavor.
At the very least, do not fertilize your tarragon. Do not provide more than 2-3 inches of water a week, if you can help it.