The geraniaceae family is a large diverse one. It can be confusing to those who are not familiar with all the relatives. The commonest, and best known one, is actually not a "geranium", but a pelargonium. The true geranium is a cold hardy , usually, but not always, low growing plant that is widely grown in rock gardens, and edgings. It likes shade, something a pelargoniun does not like too much of. It survives below zero temperatures by dying down in the fall and re-emergiing the next spring the same as a daffodill or daylilly.
Pelargoniums are divided into more than one category, the species, and garden hybrids, often called cultivars, short for cultivated varieties. These cultivars are the common garden plants that are so familiar, growing in parks, and a lot of them in home gardens, in pots, baskets and in window boxes. There are a lot of red ones seen, as it is the favorite color, though they come in pinks, oranges, purples, white, salmon and a host of colors in between. They are all cold intolernt, pelargoniums will not survive temperatures much below freezing, 32(F). They must have winter protection, unlike their cousins the true hardy geraniums.
The mix up in names occurred in the 1700s when botanists thought that they were all the same, but later found that altough related, there were differences, so separated the family into sub groups, Geranium, Pelargonium, Erodium, Monsonia and Sarcocaulon. Some now put the Mosnonia and Sarcocaulons as one plant category rather than two.
We use the incorrect name "geranium" as it had been used by gardeners for so many years before, changing to pelargonium would confuse gardeners, including nurseries who still sell "geraniums" rather than the proper, pelargoniums.
The original "geraniums" properly pelargonium, originated in South Africa. Those first brought to Europe, principally England, were not as large flowered and diverse of color as today. Hybridizers have worked with them for several hundred years and still do, giving us ever lovelier plants for our gardens.
In the pelargonium parentage is the species that are still the same as when first introduced into cultivation in Europe. In the pelargonium cultivars group, a very diverse range of lovely plants can be found, all highly collectible, some are well known, others are not. The best known is a regular garden "geranium" called commonly, zonal for the zone in the leaf. Flowers may be double or single.
