A shimmery blue flower and an extended blooming time are two great traits for a perennial. The long flowering Geranium ‘Johnson’s Blue’ (cranesbill) is an attractive perennial for planting under shrubs or in a border. Mine are planted under a lilac tree, where they provide bright blue colour long after the lilac has stopped blooming.
Johnson’s Blue has been flowering for a couple of months without stop. These plants are in part-shade, yet they have been covered in flowers. There are many fresh buds still ready to open and reveal their glimmering flowers. They look striking when the sun is shining on the blooms.
The flowers are a purplish blue, with faint purple lines giving an iridescent look to the petals. You can see from this closeup how much depth of colour the blooms have. A small white centre sets off the blue color. The simple open rounded petals are very appealing.
These Johnson’s Blue geraniums are about 60 cm (2 ft) tall and wide. The deeply lobed leaves are attractive before the plant starts to bloom. The stems have a loose habit, with their flowers weaving into the edges of the plants which surround them. This can look fine, depending on the neighbouring plants. If you don’t want them mixing with other flowers, they look good as a grouping around shrubs with an open base, or under a tree that doesn’t cast too much shade. They need to be sited where their loose structure looks appropriate.
Geraniums are relatively low maintenance plants. All they need is to be cut back in late fall or early spring, and to be deadheaded as their flowers fade. The dead blooms are easy to spot. The long, thin developing seed sticks out of the old bloom, giving them the common name, cranesbill. I try to cut off the finished blooms before the bill gets too long. This is one plant I prefer to deadhead with snips, rather than my fingernails, since they are sticky.
I’ve thought about trying ‘Rozanne’ and ‘Jolly Bee’ geraniums, but I’m not sure if they’ll be as hardy in zone 3. I might try planting one of each, to see if they return next spring, and compare their hardiness to Johnson’s Blue.
Perennial geraniums are another mainstay in the garden. They have attractive, long blooming flowers, and tolerate part-shade. Removing the faded blooms, and cutting back the foliage for winter are the only maintenance required.
What are your favourite perennial geraniums, and how do you place them?
Here is a followup comparison of Johnson’s Blue and Rozanne geraniums in my garden.