Bolster your garden’s defences against climate change with drought and heat-resistant pelargoniums.

Several years ago, leading charity the Royal Horticultural Society (RHS) published a report called Gardening in a Changing Climate. Key projections included “an increase in the number of dry spells” over summer months, with implications such as: “Warmer springs and autumns will extend the growing season and, therefore, some species will flower earlier and some will experience delayed leaf fall”.

As pelargoniums are native to South Africa, plants are already well suited to surviving extremes of heat and drought, while they’re famous for a long flowering season, too.

If predictions of milder, frost-free winters also become reality, pelargoniums will enjoy an even longer season of flowering than they do presently, with plants already renowned for blooming late into autumn, long after other summer bedding favourites have withered and gone to seed, flowering profusely right up until the frosts.

The consequences of milder winters drive demand for plants that offer high levels of pest and disease-resistance. It can require prolonged periods of sub-zero temperatures to successfully kill overwintering pests, so predictions of warmer winters raise the spectre of significant pest infestations in the future.

The good news is that pelargoniums are some of the most pest and disease-resistant plants that gardeners can grow. Slugs and snails, for example, consistently voted one of the worst plant-wreckers, often see populations bolstered by mild, wet winters. Fortunately, pelargoniums offer superb slug-resistance, as molluscs despise plants’ robust stems and thick, fleshy, unpalatable leaves. Instead, slugs and snails will make a beeline for other bedding plants, preferring to feast on their succulent young growth – leaving pelargoniums mostly untouched.

The RHS report also points out: “It is expected that warmer conditions will favour the spread of existing pests and diseases, in addition to aiding the establishment of new cases.” Again, pelargonium growers have little to worry about, as occasional infestations of sap-sucking insects such as whitefly can easily be controlled with organic bug killers.

Plants are remarkably resilient during wet spells, too, and the risk of diseases such as grey mould can be reduced by providing good air circulation, which is easy to achieve by planting at moderate densities, leaving sufficient space between plants for good air flow. And while a summer deluge – another phenomenon that’s predicted to become commonplace with climate change – can knock many popular bedding plants for six, pelargoniums are renowned for their ability to emerge unscathed, proudly displaying their rounded clusters of vivid flowers throughout summer downpours.

How can we be confident that our climate is shifting to a pattern for hot, dry weather that’ll suit heat and drought-loving plants? When it comes to global warming, the facts speak for themselves. According to the National Centres for Environmental Information, which monitors average global temperatures, the warming trend started in the mid-1970s and has been gathering pace ever since. Worldwide, the warmest years have all taken place since 1998 – with the top 10 being 2016, 2019, 2015, 2017, 2018, 2014, 2010, 2013, 2005 (tied) and 1998, respectively. NASA has confirmed that 2016 was the warmest year on record, with most of the warming pattern occurring within the past 40 years – and the six warmest years on record have taken place since 2014.

While it is remains to be seen how the effects of climate change will impact the gardens of Europe in future decades, experts are confident that extreme weather events generated by rising global temperatures are increasing in frequency.

Gardeners are widely regarded as custodians of the planet – growing drought and heat-resistant plants such as pelargoniums that will thrive in a warming climate will go a long way to ensuring that our gardens remain in full bloom, and that has to be great news for both human wellbeing and the wildlife that also calls our gardens their home.

1. Blooms of pelargoniums can begin to unfold as early as May, but don’t put these tender plants outdoors until the last frosts are over.

2. Plants should be at least 18cm high when planted out in the garden, and spaced approximately 20cm apart.

3. Pelargoniums are sun-worshippers (although some will tolerate some light shade). Grow in a location where plants can bask in the heat of the midday sun.

4. Rotate containers by 90 degrees each week, to avoid plants growing towards the sun. It will help to keep container plants uniform and balanced.

5. Besonders an heißen Tagen müssen Geranien regelmäßig und reichlich gegossen werden, am besten mit Regenwasser.