In my earliest days of gardening, I had a simple and very laissez-faire approach to summer pots, which went something like this; every year, round about late May, I’d visit the nearest garden centre, enthusiastically grab whatever colourful bedding plants took my fancy and then squeeze them tightly – often very tightly – into a container.
The result was something that was gloriously gaudy but ultimately dissatisfying. There was no attempt at any sort of colour theme or consideration for the more discreet pleasures of growth habit, texture, form or scent, while I’d yet to discover the golden rule of pot planting, which is that foliage is every bit as important as flowers.
I was reminded of this last week as I watched Patrick Ardiff, head gardener of Lodge Park Walled Garden in Straffan, Co Kildare, give a master-class in how to plant up the perfect summer pot. Ardiff is well-known for his carefully considered plant combinations in which he artfully uses foliage as the backdrop to a subtle tapestry of flowers, and "Patrick's pots", as Lodge Park's owner Sarah Guinness describes them, are one of the highlights of any summer visit to this charming garden.
His first rule – an important one – is to choose the most generously sized container you can lay your hands on. In his case, this is any one of several dozen vase-shaped terracotta pots, each standing at least 50-60cms tall and with a diameter of roughly 60cms.
These he fills with John Innes-based potting compost to within 15cm of the rim, before gently firming it down.
When it comes to planting schemes, Ardiff works within a particular colour palette (silvery foliage plants and complementary pastels are a Guinness family favourite) and follows what he calls “the rule of thirds”, which is two-thirds flowers to one-third foliage.
To save on costs as well as to guarantee their availability, he propagates a profusion of tender perennials including argyranthemums, salvias, pelargoniums, fuchsias, heliotropes, plectranthus and helichrysums from semi-hardwood cuttings taken the previous autumn, with just one mature plant capable of producing anything up to 40-50 hearty offspring. While Ardiff has a heated glasshouse, any gardener could do the same – all that’s required is a bright, frost-free spot in which to overwinter them.
When it comes to choosing flowering plants, both floriferousness and a long period of bloom are key. Planted into a good growing medium, kept regularly dead-headed, adequately watered and well-fed, argyranthemums (or marguerites) will produce an abundance of wiry-stemmed daisy-like blossoms in a variety of different colours from early summer until the first frosts, which is why they’re one of the mainstays of Lodge Park’s summer displays.
Other favourites include the peacock-blue Salvia cacaliifolia , the faded-purple Diascia 'Blue Belle' and the white-and-blue Osteospermum 'Silver Sparkler' as well as pansies, verbenas, purple-flowering bacopa and trailing, pale-blue surfinias that, if given a warm sunny summer, will quickly produce a curtain of vividly colourful flowers.
For perfume, Ardiff uses scented-leaved pelargoniums whose aromatic foliage releases a whoosh of fragrance when brushed against. His favourite is the pale-pink and purple flowering P ‘Attar of Roses’ (AGM) but there are many other varieties whose foliage scents range from cola to nutmeg (see scentedgeraniums. co.uk).
Trailing foliage plants such as the woolly leafed helichrysums (both the grey H petiolare and the lime green H. 'Limelight') are other staples, as is Plectranthus argentatus , whose silvered, velvety leaves are the perfect foil to almost any combination of flowers. Strangely hard to get, it can be sourced from the West Cork nursery, Deelish Plants (see deelish.ie). A close relative is coleus, a large-leafed foliage plant available in a range of exuberantly colourful and often brightly variegated varieties that include apricot C 'Wizard Sunset' and the gothic- purple C 'Black Dragon', both grown from seed in late spring. For larger leaves, try cannas or the ginger lily, Hedychium gardnerianum , while a good hardy perennial alternative would be any of the heucheras, heucherellas or tiarellas.
Ornamental grasses are another great foliage choice for a summer pot. Ardiff likes to use any one of a number of different varieties of miscanthus as a centrepiece, including the jauntily-striped M sinensis 'Zebrinus' and the arching M sinensis 'Gracillimus', dividing the mother plants into several smaller ones each spring so they never get oversized. Wispy Stipa tenuissima , feathery Hordeum jubatum , dainty Briza maxima , the copper-coloured Carex testacea , airy Panicum virgatum or the ethereal Molinia 'Transparent' are just some of the many other ornamental grasses that could also be used.
Keep the plants well-fed by using a liquid-feed every two to three weeks, starting six weeks after planting. Combined with a good watering and dead-heading regime, this should guarantee a display all summer.
