Passionflower

Passiflora incarnata

Common & Folk Names

• Maypop
• Purple Passionflower
• Passiflora
• Wild Passionflower
• Apricot Vine
• Holy Trinity Flower
• Passion Vine

Plant Family

Passifloraceae

Geographic Location

Native to the southeastern United States, from Virginia south to Florida and west to Texas, Oklahoma, and Kansas. Now naturalised in tropical and subtropical regions worldwide, including parts of Central and South America, the Caribbean, Southern Europe, and Australia. Commercially cultivated in the United States, India, and various tropical regions.

Habitat

Naturally grows in open woods, thickets, along roadsides, fence rows, and disturbed areas. Prefers well-drained soils in full sun to partial shade. Tolerates a range of soil conditions but thrives in sandy or loamy soils with good drainage. Found from sea level to moderate elevations. Can become invasive in favourable conditions, spreading via underground rhizomes and prolific seed production.

Growing Conditions

Sun: Full sun to partial shade; flowers and fruits best with at least 6 hours of direct sunlight daily

Soil: Well-draining sandy or loamy soil; tolerates poor soil but prefers moderate fertility; pH 6.0-7.5; avoid waterlogged conditions

Propagation: Sow seeds in spring after scarification and stratification for best germination; take semi-hardwood cuttings in summer; divide established plants in spring; layering is also effective

Care: Provide sturdy trellis or support for climbing vine; water regularly during establishment and dry periods; mulch to retain moisture; prune in late winter to control spread; dies back to ground in cold climates and re-emerges in spring; protect roots with mulch in borderline hardiness zones

NZ Planting Calendar

Sowing (seed): Spring (September-November) after scarification (lightly sand or nick seed coat) and cold stratification (4-6 weeks in refrigerator); germination can be slow and erratic

Propagation (cuttings/division): Take semi-hardwood cuttings in summer (December-February); divide established plants or rhizomes in spring (September-October)

Planting: Spring (October-November) after frost risk has passed; can also plant in autumn (March-April) in warmer regions

Growth: Herbaceous perennial vine; dies back to ground in winter in cooler areas, remains evergreen in frost-free regions; vigorous climber reaching 3-6 metres in one season

Flowering: Summer to autumn (December-April) with spectacular, intricate flowers followed by egg-shaped yellow fruits (maypops)

Harvest: Aerial parts (leaves, stems, flowers) harvested during flowering period (December-March) when constituents are at peak; fruits harvested when ripe (late summer to autumn)

Note: Not native to NZ; introduced ornamental and medicinal plant; grows best in warmer regions like Northland, Auckland, Bay of Plenty, and coastal areas; may not survive heavy frosts but roots often survive and resprout; can become vigorous or weedy in ideal conditions; requires frost protection in cooler regions; may be grown as annual in very cold areas

Harvesting Guidelines

Harvest aerial parts (leaves, stems, and flowers) during the flowering period when the plant is in full bloom, typically in summer to early autumn. This timing ensures maximum concentration of flavonoids and other active constituents. Cut stems in the morning after dew has dried but before the heat of the day. Harvest the upper third of the plant, leaving enough growth for the plant to recover and continue flowering. Include a mix of leaves, stems, and flowers for the most comprehensive medicinal profile. Dry quickly in a well-ventilated area out of direct sunlight at temperatures not exceeding 40°C to preserve the delicate constituents. The herb should retain its green colour when properly dried. Store in airtight containers away from light and moisture. Fresh herb can also be used immediately for tincture preparation.

Parts Used

• Aerial parts (leaves, stems, flowers) – primary medicinal use
• Fruits (maypops) – edible but less commonly used medicinally
• Occasionally roots, though aerial parts are preferred

Constituents & their Actions

Passionflower contains a complex array of bioactive compounds that work synergistically to produce anxiolytic, sedative, and antispasmodic effects. The therapeutic properties result from flavonoids, alkaloids, and various other constituents acting on multiple neurotransmitter systems.

Flavonoids:

These plant pigments represent the primary active constituents responsible for passionflower’s therapeutic effects. Some of the main flavonoids in passionflower are:

• Chrysin
• Vitexin
• Isovitexin
• Orientin
• Apigenin
• Luteolin
• Quercetin

The main actions of these flavonoids are:

• Modulate GABA neurotransmission by binding to benzodiazepine receptors, producing anxiolytic effects
• Provide neuroprotective effects through antioxidant activity
• Reduce inflammation through inhibition of inflammatory mediators
• Support cardiovascular health through effects on blood vessels and blood pressure

Alkaloids (Harmala Alkaloids):

These nitrogen-containing compounds contribute to passionflower’s central nervous system effects, though present in very small amounts. Some of the main alkaloids in passionflower are:

• Harman
• Harmaline
• Harmol
• Harmalol

The main actions of these alkaloids are:

• Inhibit monoamine oxidase (MAO) enzymes, though weakly in whole plant preparations
• Contribute to sedative and anxiolytic effects
• May enhance the effects of other constituents through synergy
• Note: These alkaloids are present in much lower concentrations than in other plants (like Banisteriopsis caapi) and do not produce significant MAO inhibition at normal dosages

Maltol and Ethyl Maltol:

Aromatic compounds that contribute to the plant’s characteristic flavour and potential therapeutic effects.

The main actions of maltol compounds are:

• Provide antioxidant properties
• May contribute to anxiolytic effects
• Enhance the overall therapeutic profile through synergy with other constituents

Glycosides:

Sugar-bound compounds including cyanogenic glycosides (in very small amounts).

The main actions of these glycosides are:

• Contribute to the overall therapeutic effect through complex interactions
• Cyanogenic glycosides are present in trace amounts insufficient to cause toxicity but may contribute to the plant’s effects
• Support the plant’s bioactivity through synergistic mechanisms

Essential Oils and Volatile Compounds:

Present in small amounts, these aromatic compounds contribute to the plant’s therapeutic profile.

The main actions of these volatile compounds are:

• Provide mild sedative effects
• Contribute to the overall calming aroma
• Support the synergistic action of other constituents

Actions with Mechanisms

Anxiolytic:
Passionflower’s anxiolytic effects result primarily from flavonoid interactions with the GABAergic system. Chrysin and other flavonoids bind to benzodiazepine receptors in the brain without causing the dependency associated with pharmaceutical benzodiazepines, which in turn enhances the inhibitory effects of GABA and reduces neuronal excitability. This mechanism decreases the neural activity associated with anxiety, worry, and nervous tension. The flavonoids also modulate other neurotransmitter systems, including serotonin and dopamine pathways, contributing additional anxiolytic benefits. Unlike some pharmaceutical anxiolytics, passionflower reduces anxiety without significantly impairing cognitive function or causing sedation at moderate doses, making it suitable for daytime use.

Sedative and Hypnotic:
The sedative properties arise through multiple mechanisms acting synergistically on the central nervous system. Flavonoids enhance GABAergic neurotransmission, which in turn promotes relaxation and facilitates the transition to sleep. The harmala alkaloids, though present in small amounts, may contribute mild MAO inhibition that increases the availability of calming neurotransmitters. Passionflower appears to increase total sleep time and improve sleep quality without causing the “hangover” effect common with pharmaceutical sleep aids. The herb works particularly well for individuals whose anxiety or racing thoughts interfere with sleep onset, as it addresses both the mental restlessness and the difficulty falling asleep.

Antispasmodic:
Multiple constituents relax smooth muscle tissue through several pathways. Flavonoids reduce calcium influx into smooth muscle cells, which in turn decreases muscle contractility and relieves spasms. The GABAergic effects contribute to muscle relaxation by reducing neural stimulation of smooth muscle. This antispasmodic action extends to the digestive tract, uterus, and bronchial smooth muscle, making passionflower useful for menstrual cramps, digestive cramping (particularly when stress-related), asthma with a nervous component, and general muscle tension. The spasmolytic effects appear to be particularly pronounced when spasms have a nervous or emotional component.

Nervine Tonic:
Passionflower provides long-term support and nourishment to the nervous system rather than just acute symptom relief. The flavonoids and other constituents support nervous system resilience through multiple mechanisms, which in turn helps the body better manage stress over time. Antioxidant constituents protect nerve cells from oxidative damage, whilst the modulatory effects on neurotransmitter systems help maintain balanced nervous system function. With consistent use, passionflower may reduce the overall reactivity of the nervous system to stressors, decrease baseline anxiety levels, and improve stress tolerance. This tonic effect makes it valuable for individuals experiencing chronic stress, nervous exhaustion, or anxiety disorders requiring long-term management.

Analgesic:
Passionflower provides gentle pain relief, particularly for pain with a nervous, spasmodic, or tension-related component. The GABAergic activity reduces pain signal transmission in the central nervous system, which in turn decreases pain perception. The antispasmodic properties relieve cramping and spastic pain, whilst the anxiolytic effects reduce the emotional distress associated with chronic pain. Research suggests passionflower may be particularly effective for neuropathic pain, tension headaches, and visceral pain. The anti-inflammatory properties of flavonoids contribute additional pain relief by reducing inflammation-related pain.

Hypotensive:
Passionflower produces mild blood pressure-lowering effects through multiple mechanisms. The anxiolytic and sedative effects reduce sympathetic nervous system activation and stress hormone release, which in turn decreases heart rate and blood pressure. Flavonoids act directly on vascular smooth muscle, promoting vasodilation and reducing peripheral resistance. Some constituents may have mild diuretic properties that contribute to blood pressure reduction. These effects are generally mild and most pronounced in individuals with stress-related or neurogenic hypertension. The cardiovascular effects make passionflower potentially useful as an adjunct in managing mild to moderate hypertension, particularly when stress is a contributing factor.

Anti-inflammatory:
Multiple flavonoid constituents exhibit anti-inflammatory properties through inhibition of inflammatory mediators. These compounds reduce the production of pro-inflammatory cytokines and prostaglandins, which in turn decreases inflammation throughout the body. The antioxidant activity of flavonoids prevents oxidative stress that can trigger and perpetuate inflammatory processes. While passionflower is not primarily used as an anti-inflammatory, this property contributes to its overall therapeutic effects and may explain some of its benefits for conditions with an inflammatory component.

Antioxidant:
Flavonoids, particularly quercetin, apigenin, and luteolin, provide potent antioxidant protection by scavenging free radicals and reactive oxygen species. These compounds protect cellular structures, including lipid membranes and DNA, from oxidative damage, which in turn supports overall cellular health and may slow aspects of ageing. The neuroprotective effects of these antioxidants are particularly relevant to passionflower’s use as a nervine, as they protect nerve cells from oxidative stress that can impair nervous system function and contribute to neurodegenerative processes.

Main Use

Passionflower is primarily used as a gentle, non-habit-forming anxiolytic and sedative for managing anxiety, nervous tension, insomnia, and stress-related conditions. It excels at calming an overactive mind, reducing racing thoughts, and easing the physical symptoms of anxiety such as muscle tension, restlessness, and palpitations. Unlike pharmaceutical anxiolytics, passionflower provides relief without significant cognitive impairment, making it suitable for daytime use when mental clarity is needed alongside anxiety relief. The herb works particularly well for generalised anxiety disorder, social anxiety, performance anxiety, and anticipatory anxiety.

For sleep support, passionflower helps individuals fall asleep more easily, particularly when anxiety or mental hyperactivity interferes with sleep onset. It improves sleep quality and reduces nighttime awakenings without causing morning grogginess or dependency. The herb combines beautifully with other nervines and sedatives such as valerian, hops, lemon balm, and chamomile for enhanced sleep support.

Passionflower’s antispasmodic properties make it valuable for tension-type headaches, menstrual cramps, digestive spasms related to stress, and muscle tension. The herb provides gentle support for individuals experiencing nervous exhaustion, stress-related fatigue, or recovery from periods of intense stress. Its mild hypotensive effects offer additional benefits for those with stress-related high blood pressure.

The herb is also used for opioid and benzodiazepine withdrawal support, where it may help reduce anxiety, agitation, and sleep disturbances during the withdrawal process, though this application requires professional supervision. Passionflower’s excellent safety profile and gentle action make it suitable for long-term use and an excellent choice for individuals seeking natural alternatives to pharmaceutical anxiolytics and sedatives.

Preparations

Infusion (tea): Steep 1-2 teaspoons (2-4g) of dried aerial parts in 250ml freshly boiled water for 10-15 minutes; strain and drink 2-3 times daily for anxiety or 30-60 minutes before bed for sleep support. The tea has a mild, pleasant flavour.

Tincture (1:5, 25-40% alcohol): Standard preparation using dried aerial parts; lower alcohol concentration is sufficient as many constituents are water-soluble, though some alcohol is needed for flavonoid extraction and preservation.

Tincture (1:2, 60% alcohol, fresh herb): Fresh herb tincture captures the full spectrum of constituents including more volatile compounds. Particularly effective for acute anxiety.

Glycerite: Useful alcohol-free alternative for children or those avoiding alcohol; use 1:5 ratio with vegetable glycerine; less effective than alcohol tinctures but still therapeutic.

Capsules: Dried, powdered aerial parts in capsule form; standardised extracts typically contain 3-4% flavonoids. Convenient for consistent dosing.

Tea Blend: Combine passionflower with complementary herbs such as chamomile, lemon balm, lavender, or valerian for enhanced effects. Use 1-2 teaspoons of blend per cup.

Dosage

Dried Herb (infusion): 2-4g, 2-3 times daily; for sleep, take one dose 30-60 minutes before bedtime

Tincture (1:5, 25-40% alcohol): 2-4ml (40-80 drops), 3-4 times daily for anxiety; 4-5ml before bed for sleep support

Tincture (1:2, fresh herb, 60% alcohol): 1-2ml (20-40 drops), 3-4 times daily for anxiety

Standardised Extract (3-4% flavonoids): 250-500mg, 2-3 times daily

Glycerite (1:5): 4-6ml, 3-4 times daily for anxiety

Topical Use: Not commonly used topically

Note: Effects may be immediate for some individuals but often build with consistent use over several days to weeks. Start with lower doses and increase gradually to find the effective dose.

Safety & Drug Interactions

Scientific Evidence

Anxiety Disorders: Multiple randomised controlled trials support passionflower’s effectiveness for generalised anxiety disorder (GAD). A systematic review of clinical trials found that passionflower significantly reduced anxiety symptoms compared to placebo. One notable study comparing passionflower to oxazepam (a benzodiazepine) for GAD found similar anxiolytic efficacy with fewer side effects and no impairment of job performance. Another study found passionflower effective for preoperative anxiety. The evidence is most robust for GAD, with emerging research on other anxiety disorders.

Sleep and Insomnia: Clinical trials demonstrate that passionflower can improve subjective sleep quality, though evidence is more limited than for anxiety. Studies show improvements in sleep onset latency (time to fall asleep), total sleep time, and sleep quality ratings. Passionflower appears particularly effective for individuals whose sleep difficulties stem from anxiety or mental hyperactivity. Polysomnography studies show increases in slow-wave sleep and improvements in sleep architecture.

Mechanisms of Action: Laboratory research confirms that passionflower extracts and isolated flavonoids bind to GABA-A receptors, though at different binding sites than benzodiazepines. Studies demonstrate enhanced GABAergic neurotransmission and anxiolytic effects in animal models. Research also supports antispasmodic, antioxidant, and anti-inflammatory mechanisms. The presence of multiple active constituents suggests synergistic effects rather than a single active compound.

Opioid Withdrawal: Preliminary clinical trials show promise for passionflower as an adjunct in managing symptoms during opioid detoxification. One study found that passionflower combined with clonidine was more effective than clonidine alone for managing withdrawal symptoms. Further research is needed, but initial results are encouraging.

Safety and Toxicity Studies: Extensive toxicology studies in animals show very low toxicity, with no adverse effects at doses far exceeding normal human consumption. Clinical trials report minimal side effects. Long-term safety studies support the safety of extended use. The harmala alkaloid content is too low to cause MAO inhibition concerns at therapeutic doses.

Western Energetics

Temperature: Cooling to neutral. Passionflower’s calming effects help cool “hot,” agitated nervous states characterised by anxiety, restlessness, and irritability. The herb reduces the heat of inflammation and nervous excitation, bringing a sense of coolness and calm to an overheated system. The cooling quality is gentle rather than strongly refrigerant.

Moisture: Neutral to slightly moistening. Passionflower neither significantly dries nor moistens tissues, making it suitable for most constitutional types. Any moistening tendency is very subtle and primarily relates to the herb’s nourishing effects on depleted nervous systems.

Tissue State: Particularly indicated for tense, constricted, and excitable tissue states. The herb’s relaxing and antispasmodic properties address tension and spasm, whilst the anxiolytic and sedative effects calm nervous system excitation. Passionflower is excellent for individuals experiencing nervous tension manifesting as physical tightness, cramping, or hyperactivity. Also valuable for atrophy and depletion when nervous exhaustion has depleted the system’s resources, as the herb provides tonic support for rebuilding nervous system resilience.

Taste

Bitter: A mild but distinct bitter quality stimulates digestive function and contributes to passionflower’s cooling energetics. The bitterness reflects the presence of alkaloids and other complex medicinal compounds. This taste quality helps “clear heat” from the nervous system and supports the herb’s calming effects on agitated states.

Sweet: An underlying sweetness, particularly noticeable in well-prepared tea, indicates passionflower’s nourishing and tonifying properties. Sweetness is traditionally associated with building and strengthening, supporting the herb’s nervine tonic effects and its ability to restore depleted nervous systems.

Slightly Astringent: A subtle astringency contributes to passionflower’s tissue-toning effects and may relate to its traditional use for various conditions. The astringent quality is very mild but adds to the overall therapeutic profile.

Plant Lore

The name “passionflower” derives from early Christian missionaries in South America who saw symbolic representations of the Passion of Christ in the flower’s intricate structure. The ten petals represented the ten faithful apostles (excluding Judas and Peter), the corona’s radial filaments symbolised the crown of thorns, the five stamens represented the five wounds, and the three stigmas represented the three nails. This religious symbolism quickly spread, and the plant became associated with spiritual contemplation and divine suffering.

Native American tribes, particularly in the southeastern United States, used passionflower long before European contact. The Cherokee used the plant as a blood tonic and for various ailments. The Houma tribe used the roots to treat earaches and wean babies from breastfeeding. Various tribes employed the plant for its calming effects, though traditional uses varied among different groups.

In early American Eclectic medicine (19th century herbal medical movement), passionflower gained popularity as a nervine and sedative. Eclectic physicians valued it for nervous exhaustion, anxiety, insomnia, and various nervous complaints. The herb appeared in the United States National Formulary from 1916 to 1936 and has remained popular in herbal medicine ever since.

The plant’s common name “maypop” refers to the sound the ripe fruit makes when stepped upon—a loud popping noise as the fruit bursts. This playful name contrasts with the more solemn religious associations of “passionflower.” Children in the southern United States traditionally played with the fruits, competing to make the loudest pops.

In folk magic and folklore, passionflower was carried or placed under the pillow to promote peace, calm troubled minds, and bring about prophetic dreams. The plant was believed to attract friendships and calm household arguments when grown around the home. Some traditions associated passionflower with love and fidelity.

The purple colour of the P. incarnata flowers held special significance in Christian symbolism, purple being associated with royalty, penance, and the suffering of Christ. This colour symbolism reinforced the plant’s religious associations and contributed to its mystical reputation.

Different passionflower species grow throughout the Americas, from the tropical Passiflora edulis (commercial passionfruit) to various ornamental species. Most medicinal research focuses on Passiflora incarnata, though some other species share similar properties and are used in traditional medicines of Central and South America.

Additional Information

Passionflower is often confused with passionfruit (Passiflora edulis), though they are closely related species with different primary uses. P. incarnata produces edible fruits (maypops) that are smaller and less sweet than commercial passionfruit, but the plant is primarily valued for its medicinal aerial parts rather than fruits. Commercial passionfruit comes from P. edulis, which is grown mainly for fruit production rather than medicinal use, though it may have some similar properties.

The spectacular flowers make passionflower an attractive ornamental vine in addition to its medicinal value. The flowers attract butterflies, particularly Gulf Fritillary and Zebra Longwing butterflies, whose caterpillars feed on the leaves. Growing passionflower provides both medicine and support for these beautiful pollinators.

Passionflower combines exceptionally well with many other herbs:

• Passionflower + Valerian for deeper sleep support
• Passionflower + Hawthorn for anxiety with cardiovascular symptoms
• Passionflower + Lemon Balm for gentle anxiety relief suitable for daytime
• Passionflower + Skullcap for nervous tension and muscle tightness
• Passionflower + Hops for restlessness and insomnia
• Passionflower + Chamomile for anxious digestion

The herb’s gentle, safe nature makes it an excellent choice for beginning herbalists and those new to herbal medicine for anxiety and sleep support. Its effectiveness without significant side effects or dependency risk provides a valuable alternative to pharmaceutical options for many individuals.

When purchasing passionflower products, quality varies. Look for products specifying Passiflora incarnata rather than unspecified “passionflower,” as other species may have different properties. Products should be greenish in colour and have a pleasant, mild aroma. Avoid products that appear brown or have lost their colour, as this suggests oxidation and degraded constituents.

Fresh passionflower makes an excellent tincture that some herbalists consider superior to dried herb preparations. If you grow passionflower, harvest during flowering and tincture immediately for the most potent medicine. The fresh plant tincture captures aromatic constituents that may be lost during drying.

In the garden, passionflower requires sturdy support and can be vigorous. It spreads via underground runners and may become weedy in ideal conditions, though it’s generally easy to manage by removing unwanted runners. In marginal climates, heavy mulching of the root zone in winter improves survival. Container growing is possible but requires a large pot and regular feeding during the growing season.

Sources

Bone, K., & Mills, S. (2013). Principles and Practice of Phytotherapy: Modern Herbal Medicine (2nd ed.). Churchill Livingstone.

Hoffman, D. (2003). Medical Herbalism: The Science and Practice of Herbal Medicine. Healing Arts Press.

Mills, S., & Bone, K. (2005). The Essential Guide to Herbal Safety. Elsevier.

Akhondzadeh, S., Naghavi, H. R., Vazirian, M., Shayeganpour, A., Rashidi, H., & Khani, M. (2001). Passionflower in the treatment of generalized anxiety: A pilot double-blind randomized controlled trial with oxazepam. Journal of Clinical Pharmacy and Therapeutics, 26(5), 363-367.

Ngan, A., & Conduit, R. (2011). A double-blind, placebo-controlled investigation of the effects of Passiflora incarnata (passionflower) herbal tea on subjective sleep quality. Phytotherapy Research, 25(8), 1153-1159.

Dhawan, K., Kumar, S., & Sharma, A. (2001). Anxiolytic activity of aerial and underground parts of Passiflora incarnata. Fitoterapia, 72(8), 922-926.

Movafegh, A., Alizadeh, R., Hajimohamadi, F., Esfehani, F., & Nejatfar, M. (2008). Preoperative oral Passiflora incarnata reduces anxiety in ambulatory surgery patients: A double-blind, placebo-controlled study. Anesthesia & Analgesia, 106(6), 1728-1732.

Appel, K., Rose, T., Fiebich, B., Kammler, T., Hoffmann, C., & Weiss, G. (2011). Modulation of the γ-aminobutyric acid (GABA) system by Passiflora incarnata L. Phytotherapy Research, 25(6), 838-843.

Akhondzadeh, S., Kashani, L., Mobaseri, M., Hosseini, S. H., Nikzad, S., & Khani, M. (2001). Passionflower in the treatment of opiates withdrawal: A double-blind randomized controlled trial. Journal of Clinical Pharmacy and Therapeutics, 26(5), 369-373.

Soulimani, R., Younos, C., Jarmouni, S., Bousta, D., Misslin, R., & Mortier, F. (1997). Behavioural effects of Passiflora incarnata L. and its indole alkaloid and flavonoid derivatives and maltol in the mouse. Journal of Ethnopharmacology, 57(1), 11-20.

Zanoli, P., Avallone, R., & Baraldi, M. (2000). Behavioral characterisation of the flavonoids apigenin and chrysin. Fitoterapia, 71(Suppl 1), S117-S123.

Patel, S. S., Saleem, T. M., Ravi, V., Shrestha, B., Verma, N. K., & Gauthaman, K. (2009). Passiflora incarnata Linn: A review on morphology, phytochemistry and pharmacological aspects. Pharmacognosy Reviews, 3(5), 175-181.

Grundmann, O., Wang, J., McGregor, G. P., & Butterweck, V. (2008). Anxiolytic activity of a phytochemically characterized Passiflora incarnata extract is mediated via the GABAergic system. Planta Medica, 74(15), 1769-1773.

Fisher, A. A., Purcell, P., & Le Couteur, D. G. (2000). Toxicity of Passiflora incarnata L. Journal of Toxicology: Clinical Toxicology, 38(1), 63-66.

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