I have bought geraniums most years, for as long as I can remember because they are one of my favourite flowering plants. I tried growing them from seed a few years ago, but they worked out quite expensive as packets usually contain only a small number of seeds. Additionally, the seed is classed as not easy yo germinate.
This year I bought three potted Geraniums, and they have provided very good colour from early June until now. I have moved them from their new large stone pot into the glasshouse in order to prolong flowering, and to protect them from the cold winter. I will watch out for any lingering whitefly or mould, and quickly nip it in the bud.
They are easy to grow, and easy to care for. Additionally, they are easy to propagate from stem cuttings. I checked for plant information on the RHS website, which is my online reference of choice, and here's what it has to say:
Genus: Pelargonium can be perennials, sub-shrubs or shrubs, sometimes succulent and mostly evergreen, with palmately lobed or pinnately divided leaves and clusters of slightly irregular, 5-petalled flowers
Horticultural Group: Zonal pelargoniums are bushy evergreen perennials with fleshy stems, rounded, palmately lobed leaves often zoned with maroon, and single or double flowers in shades of purple, red, pink, orange and white, from early to late summer
Details'Cardinalis' is a bushy plant with rounded, faintly zoned leaves and long-stalked, large heads of single, vivid magenta-pink flowers 4.5cm across, veined with orange-red
How to grow
CultivationGrow in fertile well-drained soil in full sun or partial shade. Remove spent flowers. To overwinter, grow small plants in late summer from cuttings or cut back old plants by one third and lift for storage in frost-free place to repot in spring when growth resumes
PropagationTake softwood cuttings in summer and overwinter plants in frost free conditions or take softwoodcuttings in spring
Suggested planting locations and garden typesFlower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants
How to care
Pruning / Deadhead regularly
Pests: Vine weevil, leafhoppers, caterpillars, thrips, fungus gnats and Aphids can be troublesome.Aphids are generally more problematic on over-wintered plants
Diseases: Foot and root rots can be a problem in wet soils. Grey moulds are often troublesome in wet conditions. A virus can often be a problem where cultivars are maintained by cuttings. Pelargonium rust can be damaging to zonal pelargoniums and associated hybrids.