Given a soil-based potting compost — such as John Innes No 3 — and a regular seaweed feed, the plant will grow fast and furious throughout the summer, and can reach six-and-a-half feet tall in a season. Three plants, positioned at intervals along a terrace, will make a spectacular foliage fanfare. To create the greatest impact, position the pots where light shines through the leaves, so they glow like stained glass. In winter, cut back the leaves, pull them under cover, forget about them, then bring them out in late spring for a head start the following summer.
For canna, read caramba. It’s hard to believe that this exuberant plant from Central and South America grows from a rather ugly rhizome, but right now you can find cannas at the garden centre ready grown and ready to rhumba. Team them with hot-coloured dahlias, and you have a carnival of colour and excitement. Cannas have smaller, similar-shaped leaves to banana plants, but as well as burgundy and near-black foliage, the leaves can be beautifully ribbon-striped in bronze and green.
The tall flower spikes are just as showy, with ruffled marmalade-orange, scarlet, rich yellow or pink blooms, sometimes speckled or edged with gold. Give them your sunniest spot and when summer is over, cut back the foliage and stems to about six inches and move the whole pot to a frost-free place. If you want to summon the spirit of the Mediterranean, bag yourself a bougainvillea from the houseplant section of the garden centre. Better yet, bag two so you can enjoy the mouthwatering mix of watermelon red alongside tangerine or shocking pink. Make sure you buy the shrubby, not trailing, varieties so they stay bushy, but be prepared for a determined summer breeze to demolish the blooms if you can’t provide a truly sheltered as well as sunny location, such as a windless corner of the patio. A conservatory or sheltered, sunny porch is an ideal place to make a bougainvillea feel at home.
For a plant that is native to the South American jungle, angel’s trumpets, Brugmansia, is surprisingly suited to an urban setting, where, given half a chance and a decent summer, the leafy shrub positively drips with a cascade of fabulous fluted blooms in white, apricot, cherry red or pink and even bi-coloured. Like many scented flowers, their fragrance is more pronounced at dusk. As toxic as it is sensational — all parts are poisonous — this is one plant that might be best for an adults-only garden.
Busy lizzies have suffered this year from a widespread fungal disease, so their more exotic and robust relatives, the showy New Guinea busy lizzies, are taking the limelight. They are sturdy plants with long, forest green leaves and the flashiest flowers in shades of deep red, vermilion, shocking pink and white. This is the bedding that, planted in abundance, makes the perfect, parakeet-bright match for summer’s statement plants, and will give your container displays true tropical status.
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