Goldenrod (Solidago virgaurea)

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 classical times, both Dioscorides (40-90 CE) and Pliny (23-79 CE) recommended couch grass root for poor urine flow and kidney stones. The herbalist John Gerard wrote in 1597 that 'Couch-grasse be an unwelcome guest to fields and gardens, yet his physicke virtues do recompense those hurts; for it openeth the stoppings of the liver and reins [ureters] without heat.' In times of famine, the root was roasted and ground as a substitute for coffee and flour.

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 the Native American said to have used it to cure New Englanders of typhus. Native Americans valued the herb as a diuretic and remedy for genitourinary conditions, and the root was listed in the Pharmacopoeia of the United States from 1820 to 1842, attesting to its recognized medicinal importance.

Buchu is a strongly aromatic, bushy shrub reaching about 6½ ft (2 m), with slightly leathery, dotted leaves that release a distinctive scent. Indigenous peoples of South Africa have long valued buchu as a general stimulant, diuretic, and digestive aid. In contemporary Western herbal medicine, it is prized mainly as a urinary antiseptic and diuretic, traditionally employed for cystitis, bladder infections, irritable bladder, and sometimes prostatitis.

Cleavers is a straggling, square-stemmed annual growing to 4 feet with whorls of lance-shaped leaves, clusters of small white flowers, and small round green fruits covered with hooked prickles. The name refers to the plant's ability to cling (or cleave) to fur or clothing. Common throughout Europe and North America and found in many other temperate regions including Australia, it grows prolifically in gardens and along roadsides. The Greek physician Dioscorides in the 1st century CE considered it useful for countering weariness and noted that shepherds used the stems to make sieves for straining milk.

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 and demulcent when immersed in water, making it valuable both as a food ingredient and medicinal herb.

Marshmallow (Althaea officinalis) is a downy perennial up to about 7 ft (2.2 m), with thick white roots, heart-shaped leaves, and pink flowers. Known for its high mucilage content, marshmallow soothes inflamed mucous membranes, including those in the respiratory, urinary, and digestive systems.

Pau d'arco is an evergreen tree that can reach 100 feet in height, producing pink flowers. The bark of this South American tree has been treasured for centuries in traditional medicine for its extensive health benefits. Indigenous peoples including the Incas and the Callawaya valued it as a cure-all. The tree grows in both mountainous terrains high in the Andes and in low-lying areas of Paraguay and Brazil. The prized inner bark is collected from wild-growing trees throughout the year.

Uva-ursi is a low-lying evergreen shrub growing to 20 inches tall with long trailing stems, dark green leaves that are glossy on the upper side, bell-shaped pink flowers, and small glossy red berries. The name means 'bear's grape' in Latin, as bears are fond of the fruit. Native to Europe and naturalized throughout the northern hemisphere up to the Arctic, it grows in damp undergrowth, heathland, and grassland conditions. The plant was first documented in The Physicians of Myddfai, a 13th-century Welsh herbal text.