The negative meaning of "Trotz" refers to a (childish) behavior in a kind of resistance. The way of your interpretations.
In a positive sense means "Trotz" resistance - against strong (environmental) factors (heat, aphids, height growth for seeds).
The best translation would be: "Brown Resistive (resistant) head".
This presumably means that this species tolerates (resists) heat without immediately to form a flower growth. The brown leaves helps to keep the aphid infestation low.
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