01.
Pennyroyal: A Bit of Botany
a little botanical information on pennyroyal

description
Mentha pulegium is the smallest of the perennial mints in the Lamiaceae family.

Two varieties are common, the variety decumbens, has weak, prostrate stems, bluntly quadrangular, 3 inches to a foot long, which readily take root at the lower joints or nodes. The leaves are opposite, shortly stalked, more or less hairy on both sides, round/ oval, grayish green, about 1 to 1 1/2 inch long and 1/2 inch broad. The flowers are in whorled clusters of ten or a dozen, rising in tiers one above the other at the nodes, where the leaves spring in pairs, beginning about the middle of the stem, their color reddish purple to lilac blue, and in bloom during July and August. The seed is light brown, oval and very small.

The other variety, erecta, has much stouter stems, not rooting at the nodes and not decumbent, but erect or sub-erect, 8 to 12 inches high. It is rarer, but the best for cultivation, as it can be reaped and tied up in bundles easily, whereas the stems of decumbens form a dense green turf. The leaves of either, when crushed, have a spearmint-like scent.

common names & nomenclature
One of its popular names is pudding grass, from being formerly used in the stuffing for hog's puddings.

Also known as:
pennyroyal, european pennyroyal, squaw mint, mosquito plant, pulegium, run-by-the-ground, lurk-in-the-ditch, pudding grass, piliolerial

Pennyroyal, the natural pest deterrent
02.
Pennyroyal: Where in the World
habitat and range for pennyroyal

Mentha pulegium is native to most parts of Europe and parts of Asia.

03.
Pennyroyal: Cultivation & Harvesting
considerations for growing and harvesting pennyroyal

climate
Grows in moist meadows and by streams in sun to part shade.

soil
Prefers sandy soils, does not tolerate dry soil well.

growing
Sow seed in spring in a cold frame. Germination is usually fairly quick. Transplant the seedlings into individual pots when they are large enough to handle and plant them out in the summer.

Mentha species are very prone to hybridization and so the seed cannot be relied on to breed true. Even without hybridization, seedlings will not be uniform and so the content of medicinal oils etc will vary. When growing plants with a particular aroma it is best to propagate them by division. Division can be easily carried out at almost any time of the year, though it is probably best done in the spring or autumn to allow the plant to establish more quickly.

harvesting
The leaves are harvested in the summer as the plant comes into flower and are dried for later use.

preserving
Store dried pennyroyal in an airtight container in a cool, dry place.

04.
Pennyroyal: The Rest of the Story
pennyroyal history, folklore, literature & more

Pennyroyal became popular during the first century after the Roman naturalist Pliny noted the aromatic plant repelled fleas, hence its name, fleabane. When rubbed on the skin or strewn, it also repels other insects, hence such common names as tick weed and mosquito plant.

During the early middle ages, pennyroyal was recommended for truly bizarre purposes. Physician/philosopher Saint Albertus Magnus wrote that by covering drowning bees in its warm ashes, "they shall recover their life after a space of one hour," though it remains unclear why anyone would want to revive drowning bees.

For repelling insects, rub fresh, crushed plant material around the body, or mix pennyroyal tincture into a skin cream and rub that on.

For an herbal pet flea collar, try a pennyroyal garland or a bag of the herb hung from a regular collar.