How to Grow Pelargoniums

Pelargoniums are tough, water wise plants that can provide a big splash of colour for minimal effort.  You’ll probably know these plants better as geraniums, and for a long time, they have been taken for granted, tucked away in neglected corners of the garden.  Early botanists lumped perlargoniums with a group of similar plants already known as geraniums and the name has stuck with gardeners ever since.

There are 5 major types :-

1. The ivy leave pelargoniums, which derive from a single distinctive species pelargonium peltatum, has a leave that looks like English ivy and has a wonderful trailing habit, which makes the plant a useful groundcover.  They have lovely, delicate flowers often with intricate patterning.

2. Zonal pelargoniums have really cute flowers, but for these plants it’s all about       foliage.  They derive their name from the zones or bands of colour in the leaves.  Zonal pelargoniums produce so much foliage that a collection of dead leaves builds up underneath and should be removed to stop fungal diseases.

3. Regal pelargoniums develop a shrubby habit in the garden and are more upright growing.  With rounded, deeply serrated leaves and wide trumpet shaped flowers, often exotic in colour, it is the spectacular flower, which makes them great for pots, courtyards and flowerbeds.

4. Dwarf and miniature zonal pelargoniums are 13 – 20cm tall measured from the soil to the top of the plant, excluding stem length and flower, making them excellent plants for pots and window boxes.  The miniature zonal plants are floriferous with double and single blooms in a wide range of colours and having green to greenish-black leaves.

5. Scented-leaved pelargoniums have small, delicate flowers with five petals and fragrant foliage, for which they are chiefly grown.  They make excellent houseplants and in warmer climates can be grown outside as bedding plants.

Pelargoniums produce flower buds all year round and to keep them coming just pinch out the old flower stems as they finish and the plant will look after itself.  Pelargoniums can be grown in all types of well-drained compost, providing it is fresh and has been kept out of direct sunlight.  Care needs to be taken with watering however as some composts can drain more freely than others and pelargoniums need to be kept on the dry side until well established.  They then need plenty of watering during the growing season.

Give pelargoniums a weekly application of a high potash fertilizer.  Start these feeds three weeks from potting up and throughout the summer.  This helps the plants to continue to produce a mass of good quality blooms without becoming too leafy.

Pelargoniums are one of the easiest plants to propagate and the propagation method is the same for all varieties.  Taking cuttings is an inexpensive way of producing new plants whilst maintaining older plants shape and size.

Selecting the Cuttings

Although it is possible to take cuttings from spring onwards it is best to take your cuttings in the summer months when lighting conditions are good and the weather is warm.  Select strong healthy shoots (non-flowering ones from regal or scented leaves varieties).  Cutting just above the 3rd joint below the growing tip, trim each cutting just below the lowest joint and remove the leaves.

Inserting the Cuttings

Choose a pot size suitable for the number of cuttings, for example a 13cm pot will take about 5 cuttings.  Fill the pot with standard seed or cutting compost, press down firmly and place the pot in a container of water until the compost becomes moist.  Remove the pot and allow it to drain.  Insert the cuttings, pressing them down to eliminate any air beneath the base of the cuttings and do not water.

Aftercare

Place the pot in a light, warm position, but not in full sun.  One week after water the cuttings, again from below by putting the pots back in water.  Water again another week to 10 days later, again from below and by this time the cuttings should be rooting.  Remember never water the cuttings from above or cover with plastic as this could cause grey mould, botrytis or other damping off diseases.  Always allow free circulation or air around them.  When the cuttings have rooted and fresh leaves start to appear pot them up singly into 7cm pots.