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Geraniums

What’s in a geranium’s name? Confusion

Pelargoniums
These geraniums are really Pelargoniums…
RHS Plant of the Century, geranium Rozanne
… while this is a real geranium or cranesbill

 

 

 

 

 

 

 

One of the plants I’m sentimental about is the zonal geranium. I was given a cutting of a pink one by my Uncle George when I was eight – it’s still going strong.

One thing to clear up now – names. Geraniums are really Pelargoniums, but nobody really calls them that. Proper geraniums are the hardy herbaceous perennial cranesbill type – not these half-hardy, showy favourites of the Med, alpine balconies and cottage garden.

There’s two main types – zonal (because of the often pronounced ‘zones’ on the leaves), and ivy-leaved, which have smoother leaves and a trailing habit.

Zonals are my favourite, with their fuzzy leaves and peppery smell – ivies tend to attract greenfly.

Many other branches of the family exist – angel, decorative, double zonal, regal, stellar, rosebud and scented leaved.

They are easy to look after – my motto is ‘treat them mean to keep them keen’. I hack them right back to overwinter in the conservatory and greenhouse.

By March, I increase watering and top-dress the pots with fresh compost. Mine all go outside in summer until the first frosts. Keep them well fed and deadhead regularly and they’ll perform well in a sunny spot.


Scent of Turkish Delight…

Scented geranium Angel's Perfume
Scented geranium Angel’s Perfume

I have an especial a weakness for scented-leaved geraniums and the plug plant collection from The Vernon Nursery didn’t disappoint.

In 2015’s damp, cool summer, they outperformed all other types. It used to be said they don’t have the floral beauty of the others, but Angel’s Perfume is a new scented type, combining the looks of an angel geranium with the aroma of a scented leaf variety.

The ruffled foliage is sweetly lemon scented, with pansy-like flowers. Height 30cm, three plug plants £9.99.

Scented geraniums
Bit of a colour clash – scented geraniums with Bullseye Scarlet

Of the traditional types, my favourite is Attar of Roses, which smells like roses/Turkish delight; Scented Citriodorum (citrus); Clorinda (cedar) and Torento (ginger/cola). Four of each plug plants in the 2015 collection, £29.99 (note – the collection has changed slightly since then).

Finally, not a scented type, but a new plant exclusive to Vernons, Spanish Wine Burgundy, a zonal geranium with rich burgundy blooms sitting high above the compact rich green foliage. Each petal is edged with a light pink picotee.

It repeat flowers right through summer and into late autumn. Height 45cm, five plug plants for £11.99.


Geraniums on trial

Geranium cuttings
Geranium cuttings from my own stock

In 2014, I trialled more than 100 geraniums in pots – cuttings, seeds, bedding plug plants and specialist named varieties.

In May, they were at vastly different stages. By the end of the season, all had put on a decent show.

The plug plants, from online nursery, Plant Me Now, were zonals Bullseye Scarlet; Bullseye Light Pink; New Century White; New Century Violet and ivy-leaved Supreme Blanche Roche and Precision Burgundy Red.

They performed best of all, and particularly good were the ivy-leaved varieties. Best if you want massed bedding.

Vancouver Centennial
Vancouver Centennial

A mixture of named varieties came from The Vernon Nursery, including Vancouver Centennial. The plantlets took longer to get going, but every one is a beauty. More expensive, but best if you want choice blooms in pots.

The cuttings were from my own stock, so cost me nothing. If you already have plants, this is the cheapest way to do it.

Geranium Black Magic leaf
Geranium Black Magic leaf

I grew F1 Black Magic Mixed from seed, a mix of scarlet, rose, apple blossom and salmon flowers, with almost black foliage and a lime green edging.

You have to have some knowledge of growing from seed, and a heated propagator – mine were sown in January. It’s worth growing them for the foliage alone, but they seem prone to grey mould attacks.

Price-wise, cuttings cost nothing; seeds – 67p per plant; plugs – £1-£1.30 per plant; specialist varieties – £3.99 per plant (prices vary with variety).


Geraniums
Going to sleep – geraniums under glass and cut back

 Waking up and overwintering geraniums

Geranium fuchsia
First flowers of the year from an unknown favourite geranium in April

New geranium leaves are a real spring bonus under glass. If plants are warm enough during winter (above about 7C), in good light and with dry air, they will continue to grow, even with reduced watering. Mine usually keep going all winter.

In March under glass, give plants a boost by repotting or top dressing with new compost and give them their first proper watering of the year. It’s messy but make sure the soil is soaked.
Trim back yellowing leaves, pinch out growing tips and get rid of flowers for now – you want the plant to build itself back up before flowering again – and check for pests.
Grey mould geranium
Grey mould on a geranium as the atmosphere was too moist

The new compost will feed the plants for a few weeks before you need to consider adding plant food – or use slow release pellets in the compost.

In autumn, before bringing them under glass, clean off dead leaves or dying flowers and check for hidden pests. Try to keep the atmosphere dry, but not the roots – the plants do not go into dormancy, so need some moisture.

Ventilation is important, to prevent against mould and rotting.

They only need to be frost-free, although above 5C is best – if frost damages the stems, the plant will die.