When sourcing dried hibiscus (Hibiscus sabdariffa), buyers must prioritize color, moisture content, and purity. High-quality flowers should exhibit a deep burgundy or dark red hue; a brownish tint often indicates age or improper drying. The moisture content should be strictly between 10% and 12% to prevent mold growth during transit while avoiding brittleness. Furthermore, ensure the product is 'whole flower' grade rather than 'siftings' or 'fine cut' unless specified for tea bags, as whole calyces retain essential oils and flavor better.