Top Tips for Trailing Geraniums in your Garden
Give ivy leaf geraniums a try for a summer of colour
Trailing geraniums are a popular addition to hanging baskets, but can really excel when planted on their own, in large group plantings. They are easy to grow and come in vibrant colours and in pastel shades, in single and double forms.
What's the difference between geraniums and pelargoniums?
All plants have a species or Latin name, as well as a common name. 'Geranium' is the common name for the species Pelargonium. Confusingly, 'Geranium' is also the botanical name of hardy geraniums, also known as cranesbills or 'true geraniums'. Despite sharing a common name, geraniums (pelargoniums) and cranesbills (geraniums) are different species, and have different growing requirements.
In the family Geraniaceae, Pelargonium peltatum is commonly known as ivy leaf, trailing, or cascading geranium.
An herbaceous perennial native to South Africa, P. peltatum was introduced to the cool climates of Holland and England by 1704. Winter hardy only in Zones 9-11, their fast growth and easy propagation soon saw them being used as an annual – as they still are today.
A green wall is a stackable, modular living wall system only requiring restraint fixings. Each trough is typically 60cm wide and both stacks vertically and clips horizontally, fitting any space. The 1.8L water reservoir and capillary felt allows plants to draw up the water they need and the cascading overflow system avoids the risk of overwatering and water wastage.
Pots and hanging baskets are a less expensive and more traditional option.
How to grow
Plant into in a good quality compost, irrigate moderately from spring to summer, allowing the compost to dry between waterings. Apply a balanced liquid fertilizer during the growing season and switch to a high potassium fertilizer when flowering starts. These plants thrive in full sun and don’t appreciate constantly wet compost when the leaves can become prone to downy mildew. An advantage of a hanging basket or green wall is that watering can be controlled and the plant in the rain shadow won’t be soaked by showers. Unlike most companion annuals in the same basket, trailing geraniums don’t mind drying out. Regular deadheading should mean flowers from June until the first frost.
Overwintering
These plants are tender perennials rather than annuals and overwinter well in pots in an unheated greenhouse when allowed to go dormant, and flower much earlier than plugs or seed raised plants in the following spring. They will cope with surprisingly low temperatures as long as the compost is dry. Keep them in your porch, conservatory or on a windowsill in an unheated room in the house. Mine have survived -5C, but probably no lower. Allow to dry out completely and cut back by about one third. Take off leaves that succumb to mildew. In early spring water very sparingly and cut back by another third in late February or March. They will begin to bud profusely in the greenhouse so water and feed at this stage, and bring out in sunny days. They are happy to bake in the greenhouse in March and April sunshine and will flower well with little attention. Bring out after the risk of frost has passed.
Seeds or plug plants
They are slow to grow from seeds, which need to be started early, around late January, so plug plants can be a better option. Online suppliers sell named varieties or collections of 10 or 20 plug plants for around £1 each which is my preferred option.
Propagation
Pelargoniums are usually easy to take cuttings from. You need a small pot with gritty, peat-free compost. Choose a non-flowering side shoot and make a clean cut using a sharp knife or scissors between two of the bumps (nodes) on the stem that the leaves grow from. Take just the tip, about 5cm or so, and remove the bottom couple of leaves. Let it dry out for a couple of hours, and then simply push it into the compost and give it just enough water to make the compost slightly damp. Keep the pot somewhere warm and light, but out of direct sun, and check regularly to make sure the compost is still damp, but never wet. You should soon see signs of new growth, and when you can see roots growing from the bottom of the pot, you will know you have a new little plant.
Our many thanks to Les, for sharing these wonderful tips, we hope this inspires you to add your own trailing geraniums to your garden!
