In the video below, I answer the question whether geraniums are annuals or perennials by looking at the geraniums in my garden.
So are geraniums, annuals or perennials?
Odd as it might sound in a post about geraniums, we’ll start with some plants that aren’t actually geraniums, namely pelargoniums.
Pelargoniums – are they even geraniums?
Pelargoniums and geraniums both belong to the same family, Geraniaceae, and there are enough similarities between them for them to have originally been thought to belong in the same genus.
But, although they have long been known to be separate plants, pelargoniums are still often referred to as geraniums. Therefore, you will see pelargoniums sold as zonal geraniums, ivy leafed geraniums or scented geraniums. And it is for that reason that we cover them in this post.
As an aside, it is worth noting that the word geranium is derived from the Greek for Crane, because as the common name Cranesbill hints at, the plant’s seedpods are shaped like the Crane’s bill. Interestingly, as the Laidback Gardener points out, the word pelargonium comes from the Greek for Stork. What is more, the pelargonium has seed capsules that are almost indistinguishable from the geranium’s. All of which demonstrates the close connections between the two types of plants.
So, are pelargoniums annuals or perennials?
Pelargoniums produce beautiful pink and red flowers and have fleshy stems. Their leaves are attractive, sometimes scented, with interesting leaf shapes and colouring.
In temperate climates we tend to grow pelargoniums as annuals. But they are in fact tender perennials. So, in a climate where there is no frost, they would continue to grow on year after year.
But in areas where frost occurs, pelargoniums are at risk and will be killed if temperatures fall much below freezing. Therefore, in frost prone areas, pelargoniums need to be kept in a heated greenhouse or indoors in order to overwinter successfully.
Geraniums – annuals or perennials?
Herbaceous perennial geraniums
The plants I think of as true Geraniums, like Geranium ‘Johnson’s Blue‘ are mostly hardy herbaceous perennial plants.
They will come back year after year. They’ll die back in the winter, often with attractive leaf colouring in autumn. But, they will come up with a fresh flush of growth in spring and flower for much of the summer with beautiful pink, blue or purple flowers.
Annual and biennial geraniums
But even amongst the geraniums, there is some variety of life span. Of the plants commonly grown in gardens, there are two species in particular, noted below, that are not straightforward herbaceous perennials.
Geranium maderense is an exotic look geranium species with finely cut deep green leaves and spectacular panicles of flowers held erectly above the leaves.
This is a somewhat tender species of geranium that is native to Madeira. It is technically a perennial, but is very short lived and often behaves like a biennial – flowering in its second year and then dying off.
I grew Geranium maderense once and was surprised that it didn’t last beyond a couple of years, as I didn’t know at the time that it was a short lived perennial. Of course, you can keep it going by letting set seed and raising the seeds the following Spring or by taking basal cuttings.
Geranium Robertianum (Herb Robert) is essentially a wild species of geranium in many parts of the world. It has aromatic leaves and pink flowers. It is important to cover in this context because Herb Robert it is an annual or biennial species.
Martin Cole has been an avid gardener for more than 20 years and loves to talk and write about gardening. In 2006 he was a finalist in the BBC Gardener of the Year competition. He is a member of the National dahlia Society.
He previously lived in London and Sydney, Australia, where he took a diploma course in Horticultural studies and is now based in North Berwick in Scotland. He founded GardeningStepbyStep.com in 2012. The website is aimed at everybody who has been bitten by the gardening bug and wants to know more.
Gardening Step by Step has been cited by Thompson and Morgan, the UK’s largest mail order plant retailer, as a website that publishes expert gardening content.
Check out my comprehensive step by step guide, with plain language explanations and ultra-useful images and illustrations. This is for you if you love dahlias and want to the best out of the dahlias you grow.