Plant of the Week

Iris germanica

Each week, OGV sub-committee member, Gayle Parkes presents the 'Plant of the Week'. She also posts to OGV's Instagram - make sure you check back weekly for her latest post. This week Gayle brings us Iris germanica, with its stunningly distinctive flower that comes in a rainbow of colours.

The Iris is a genus of 260–300 species of flowering plants with showy flowers. It takes its name from the Greek word for a rainbow, which is also the name for the Greek goddess of the rainbow, Iris. 

It's a magical time when iris flowers unfurl their pencil-slim buds to reveal a kaleidoscope of colour. With many different types and colours available, it seems there is an iris for nearly every garden, large, small, formal, cottage style, they even look fabulous in pots. The vast majority are hybrids with the most popular, I think, being the bearded variety. Other popular varieties include Siberian and Japanese irises, Louisiana irises that are native to North America, and Dutch hybrids.

It is Iris germanica, the bearded iris, that is stopping me in my tracks at the moment.  I am seeing these intricate and exquisite blooms in so many gardens around my area and even found myself stopping the car to photograph the mauve beauty you can see here. What a perfect example of this week’s Plant of the Week!

This evergreen perennial spreads by creeping rhizomes that form large clumps over time. In spring it produces stunning silky textured, flag-like flowers that come in a wide range of colours including yellow, gold, lavender, mauve, purple, brown and white. Many have combinations of more than one colour making them truly spectacular!

The distinctive six-petaled blooms have three outer hanging petals (called “falls”) and three inner upright petals (called “standards”). Nature is quite remarkable!

Bearded iris should be planted in a sunny spot in late summer. The plants need well-drained soil and at least six hours of sunlight per day. A full day of sun is even better to keep the rhizomes dry. 

Ensure that the top of the rhizome is placed just at soil surface and the roots are fanned out either side then covered in soil. Set rhizomes at least 30cm apart. It is said that there are only two reasons why a bearded iris does not flower; either the rhizome is planted too deep or the plant is not getting enough sun. Many, many years ago when I started gardening I learned this the hard way, planting my irises like one would plant a daffodil bulb….!

Try not to over water your irises as the rhizomes are susceptible to rot. This is one plant that doesn’t like mulch as this can also encourage rot. Watch out for the snails too.

Iris plants are abundant multipliers….. great news for our friends and neighbours. They are often passed down from generation to generation and are very popular at the “swap table” at garden clubs around the world. Once the rhizomes become crowded, flowers may be limited indicating the rhizomes need to be separated. It’s a good idea to make dividing a habit. Divide your irises every three to four years in late summer when the plant is dormant.

Iris germanica is among the most elegant and colourful perennial you can grow. To see a border of flowering iris is a sight to behold. To visit Monet’s garden in Giverny was for me, a dream come true. Over the centuries they have been the go to flower of water colourists and oil painters alike, the often featured flower of lead light artists and now, their images are being “coloured in” by young and old.

With a little know-how, you too can grace your garden with long-lasting, ever-multiplying blooms for years to come, be it the pretty soft pastels or the big, bold purples and golds, and like a rainbow, the many colours in between.