The four workhorses
Dried apple supplies body and sweetness cheaply. Hibiscus supplies acidity and colour. Blackberry leaf supplies the tannin that stops the drink tasting like hot squash. Rooibos supplies body in caffeine-free blends. Between them they are the base of a very large share of what is sold as fruit or herbal tea.
Why that is not a scandal
Dried fruit alone tastes tart and vague, because drying removes the volatile compounds that make fresh fruit smell of fruit. A blend needs something to carry it. The problem is not that a base exists; it is that the packet’s picture implies the base is not there.
Reading the list
Ingredients are ordered by weight. If apple and hibiscus come first and the named fruit is near the end, you know what you have. This takes five seconds and it is the single most useful habit in this category.
What a good blend looks like
The named ingredient high in the list, a base that suits the drink rather than whatever was cheapest, and either no flavouring or flavouring declared plainly. Visible petals tell you nothing either way — cornflower and calendula are in the packet for the buyer’s eye.