Pau d'Arco (Tabebuia impetiginosa)

Couch grass is a vigorous perennial growing to 32 inches with a long, creeping rhizome, slender leaves, and erect spikes bearing green flowers aligned in two rows. Found in Europe, the Americas, northern Asia, and Australia, it is an invasive weed harvested throughout the year. In times of famine, the root was roasted and ground as a substitute for coffee and flour.

Andrographis, commonly known as Green Chiretta or King of Bitters, is an upright annual herb reaching approximately 3 feet in height. Native to India and cultivated throughout northern regions of India and China, this bitter medicinal plant has been valued in Ayurvedic and traditional Chinese medicine for centuries. MSK notes that it has been studied mostly for colds, flu and upper respiratory infections. The plant thrives on plains and in forest undergrowth, where its spotted pale brown or purple flowers and long seed capsules distinguish it from other medicinal herbs.

Calendula (Calendula officinalis) has bright orange daisy-like flowers.

For many people the scent of eucalyptus conjures up days spent in bed during childhood with eucalyptus and other oils smothered on the chest. Eucalyptus is a common ingredient in many over-the-counter cold remedies.

Goldenrod is a perennial plant growing to 28 inches with toothed leaves and branched spikes of golden-yellow flowers. Native to Europe and Asia and naturalized in North America, it prefers open areas and hillsides and is gathered in summer while in flower. The herbalist John Gerard commented wryly in 1597 about how goldenrod's value plummeted once it was discovered growing locally in Hampstead wood, London, noting society's tendency to esteem things only while they remain rare and foreign. Four hundred years later, this observation still rings true.

Gravel root is an erect perennial growing to 5 feet with whorls of pointed oblong leaves and clusters of purple-pink florets. Native to eastern North America, the root is unearthed in autumn. The plant's alternative name, Joe Pye weed, honors a Native American named Joe Pye. The root was listed in the Pharmacopoeia of the United States from 1820 to 1842.

Irish moss is a reddish-brown seaweed growing to 10 inches, with a flat, forked plant body and fan-shaped outline. Found on the Atlantic coasts of Europe and North America, it grows just below the waterline, attached to rocks and stones. In summer in North America and in autumn in Ireland, it is pulled up by hand or with a rake at low tide and dried in the sun. This seaweed is used extensively in the food and pharmaceutical industries as an emulsifying and binding agent, appearing in products such as toothpastes. Its polysaccharides become jelly-like when immersed in water, which makes it useful as a food ingredient.

White mulberry is a deciduous tree cultivated for over 5,000 years, primarily known as the preferred food source for silkworms. The leaves contain flavonoids along with vitamins A, B1, B2 and C.