Butterfly Pea Flower Tea
The colour-changing blue infusion that turns purple with a squeeze of lemon — mild, earthy and mesmerising.
Few herbal teas are as visually striking as butterfly pea flower. Steeped in hot water, the dried blue flowers release a vivid indigo colour that seems almost too vivid to be real. Add a squeeze of lemon and the pH shift turns the cup from blue to purple — a transformation that never loses its charm, no matter how many times you have seen it.
Beyond the spectacle, butterfly pea flower tea is a genuinely pleasant drink: mild, earthy and slightly floral, with a subtle woody undertone. It has been a fixture of traditional South and Southeast Asian cuisine for generations, used to colour rice, cakes and drinks long before it became fashionable globally.
This guide covers the botany, history, flavour, and brewing of butterfly pea flower tea from an educational angle. Nothing here constitutes medical advice; see our disclaimer.
Botanical overview
Clitoria ternatea is a climbing perennial vine with striking bright-blue flowers. It is a legume — unrelated to true tea or common herbal tea plants — grown widely across tropical Asia as a food dye source, traditional medicine plant, and protein-rich forage crop.
The vivid blue colour comes from anthocyanin pigments called ternatins. These are pH-sensitive: they shift from blue to purple in the presence of acid — which explains the colour change when lemon juice is added. For tea, only the dried flowers are used.
- Botanical name
- Clitoria ternatea
- Plant family
- Fabaceae (the legume or pea family)
- Part used
- Dried flowers
- Origin
- Tropical Asia; now cultivated across South and Southeast Asia, Africa and the Caribbean
Traditional uses
In Thailand, butterfly pea flower is known as anchan and has been used for centuries to colour sticky rice and traditional sweets. In Malaysia, the rice dish nasi kerabu owes its vivid blue colour to these flowers; in Malay ceremonial culture the plant carries symbolic associations and appears in traditional medicine.
In India and Sri Lanka it has been part of Ayurvedic practice for a long time — referred to in Sanskrit texts as shankhapushpi, though that name can apply to more than one plant species. Butterfly pea flower has recently become fashionable in specialty cafes worldwide, but its culinary history in Asia is far deeper than its current trendiness implies.
What the science says
The blue anthocyanin pigments — the ternatins — have attracted laboratory interest, and a small number of human or animal trials have been conducted exploring their properties. As with many herbal compounds, the gap between laboratory observations and what happens in someone drinking a cup of tea is significant, and we keep our language accordingly measured.
What is straightforwardly true is that butterfly pea flower tea is caffeine-free, visually vivid, and has a long track record of safe culinary use in Southeast Asia. The colour-changing chemistry is well understood and entirely natural — no additives required.
Educational only. This section summarises traditional context and general, science-aware information. It is not medical advice and does not describe treatment. See our disclaimer.
Flavor & aroma
Flavor profile
The flavour of butterfly pea flower tea is surprisingly mild given its visual drama. It is earthy, slightly woody, and gently floral — closer to a mild green vegetable than a fruity herb. The taste alone, without the colour, would not stand out among mild herbal teas.
This mildness is part of its appeal: it acts as a visual centrepiece in blends without dominating. Any tartness in a lemon-spiked version comes from the lemon, not the flower. For more flavour, blend with hibiscus, lemongrass, or ginger.
Aroma
Dried butterfly pea flowers have a delicate, slightly earthy floral scent. When brewed, the aroma is gentle — a faint earthiness and the faintest trace of floral sweetness. It is not a particularly aromatic tea by itself, which is why it so often appears in flavoured or blended preparations.
How to brew Butterfly Pea Flower Tea
Butterfly pea flower brews best at 90°C — slightly below a full boil. This protects the delicate pigments and produces a cleaner, more vivid blue; fully boiling water can sometimes push the colour toward a murkier, greener hue.
Use 5–7 dried flowers per cup. Colour deepens with quantity and steep time. Brew in a clear glass and have lemon juice ready to add at the table for the full colour-change effect.
Heat fresh water to 90°C (just below boiling — turn off the kettle just before it reaches a full boil).
Add 5–7 dried butterfly pea flowers per cup into your infuser or teapot.
Pour the water over the flowers. You will see the vivid blue colour develop almost immediately.
Steep for 4–5 minutes, then remove the flowers or strain.
Serve in a clear glass for maximum visual effect.
Add a squeeze of fresh lemon or lime juice and watch the colour shift from blue to violet-purple.
| Setting | Recommended | Notes |
|---|---|---|
| Water temperature | 90°C / 194°F | Heat matched to this botanical |
| Steeping time | 5 minutes | Cover while steeping; taste to finish |
| Ratio | 1–2 tsp (2–3g) per cup | More herb for a bolder cup |
| Caffeine | Caffeine-free | Great any time of day |
Serving & pairing
Serve butterfly pea flower tea in a clear glass so the colour can be appreciated fully. With lemon and honey over ice it becomes one of the most eye-catching iced teas imaginable. Its mild flavour is a natural canvas for additions — ginger, lemongrass, or mint all work well.
It is also widely used as a natural food colouring in cocktails and lemonades; the colour-change chemistry works equally well in a pitcher.
- Lemon or lime juiceThe classic partner — triggers the blue-to-purple colour change and adds welcome tartness.
- LemongrassA natural blend companion from Southeast Asian tradition; adds citrusy brightness.
- HoneySoftens any earthiness without affecting the colour drama.
- Fresh gingerAdds warmth and spice to balance the flower's mild, earthy character.
Storage tips
Dried butterfly pea flowers are relatively stable, but light is their particular enemy — prolonged exposure to sunlight can bleach both colour and flavour. Store them in a dark, airtight container: a tin or dark glass jar is ideal.
Stored properly away from heat and moisture, dried flowers should remain vividly blue and fragrant for up to 12–18 months. If the flowers have faded to a dull grey-blue, both the colour and subtle flavour of your brewed tea will be disappointing.
Beginner advice
Butterfly pea flower is one of the most beginner-friendly herbs — there is almost no wrong way to brew it. The main variable is the quantity of flowers, which controls how deep and saturated the blue becomes.
For a first brew, try seven flowers in a clear glass mug with 90°C water, then add a squeeze of lemon and watch the colour shift. From there, experiment with other flavours to find a combination you enjoy drinking as much as watching.
Interesting facts
- The vivid blue colour comes from pH-sensitive anthocyanin pigments called ternatins.
- Any acidic ingredient — lemon juice, lime, vinegar — shifts the colour from blue toward purple or pink.
- Butterfly pea flower has coloured Thai sticky rice and Malaysian blue rice for centuries.
- The plant is a legume — in the same family as beans and lentils, not related to mint or daisy plants.
- It cold-brews beautifully overnight in the fridge, producing a clear, vivid blue infusion.
Common myths
- The colour change is caused by food colouring or additives.Reality: The shift is entirely natural chemistry. The anthocyanin pigments in the flower are pH-sensitive; acid makes them purple, neutral or alkaline water keeps them blue. No additives needed.
- Butterfly pea flower tastes as dramatic as it looks.Reality: The flavour is mild and earthy — pleasant but subtle. The visual drama is the main event; the tartness in a lemon-spiked version comes from the lemon, not the flower itself.
- All blue-coloured teas contain butterfly pea flower.Reality: Not necessarily — some products use synthetic colourants or other sources of blue pigment. Check ingredient labels if authenticity matters to you.
How it compares
| Tea | Colour | Flavour | Colour change? |
|---|---|---|---|
| Butterfly pea flower | Vivid blue / purple | Mild, earthy | Yes — blue to purple with acid |
| Hibiscus | Deep crimson | Tart, fruity | Slight shift with pH |
| Rosehip | Ruby red | Fruity, tart | No |
| Rose petals | Pale pink | Floral, delicate | No |