Lavender Growing Tips

Hi everyone,

I’m trying to understand what went wrong with our lavender and would really appreciate some advice.

We kept it for about 2–3 months in a Click & Grow 9 alongside basil, lettuce, and purple chili, all of which grew really well. The lavender, however, gradually became thin and weak.

We then tried to rescue it by taking it out of the unit and placing it in a vase (see picture), but unfortunately it still died.

As you can see, instead of growing into a bush, it is taller and dispersed. Has anyone experienced something similar with lavender in Click & Grow?
Any tips for growing it successfully next time, or things we should avoid?

Thanks in advance!