Hardy Geraniums are lovely plants that offer loads of brightly coloured flowers carried above decorative foliage. Not to be confused with tender bedding geraniums which are more correctly known as Pelargonium, Hardy Geraniums are commonly known as cranesbills and they grow without fuss and flower reliably. They are often overlooked by gardeners, but there is a huge variety (500 different types) of Hardy Geraniums to choose from. Some are evergreen, while others have lovely autumn leaf colour. They are generally very long flowering, require little attention and are ignored by pests and diseases.
This video shows you how to divide perennial plants to make them go further.
Geraniums are generally very adaptable and forgiving plants which will tolerate most soils (unless really waterlogged) and, as a rule, cope with either sun or shade. The exceptions are the smaller species which do need sun and free-draining soil.
- During the growing season, feed with a balanced fertiliser every month and water during prolonged dry spells.
- In the winter they will prefer to be kept quite dry.
- Pruning off the dead flower heads will encourage further flowers later in the season.
- The foliage of some varieties can look tatty by mid-summer, but they can be cut back hard with shears to encourage a further flush of fresh foliage. Give trimmed plants a thorough soaking and a boost with a high-potash fertiliser, such as tomato feed.
- Geraniums are fairly trouble free although they can be attacked by vine weevil larvae, slugs and snails. Also, in dry conditions, they may suffer from powdery mildew. A good layer of mulch applied in spring will help to combat this. The mulch helps maintain the soil moisture level which will prevent the water stress that encourages the fungus.
- Geranium seeds can be sown outside in containers in spring. Collecting seeds from plants in the garden can be a difficult process as the seeds have to be gathered at exactly the right time so that they are ripe, but before they fall.
- It is much easier to take cuttings in spring. These should root well given some bottom heat.
- Larger clumps can be divided in spring which will help them generate lots of fresh new growth and give you more plants to move around your garden or give to friends.
Hardy geraniums range in size from ground-smothering plants that grow to 25cm (10in) high up to border beauties reaching 1.5m (5ft). On the whole they can survive in almost any garden situation from hot, dry and sunny, to cold damp and shady. They can be planted in alpine gardens, in pots, in the middle of the border, at the front of the border or as ground cover.