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Garden AdviceSummer

Summer Colour

As per usual after Christmas, summer is just beginning. It's not too late to plant those colourful flowering plants that will sizzle their way through the hottest months, well into autumn.

If you want your flowers to stand out, steer clear of too many pastel shades. Summer's hottest oranges, yellows and reds hold their own in our strong UV light. Break up blocks of hot colour with plenty of green foliage and contrasting splashes of blue and purple.

Annuals offer the most inexpensive way to start a summer flower border. Starting your on from seed is very cost effective, and offers the widest choice of varieties, but at this time of year ready grown seedlings are the best option. Look out for summer specials on petunias, zinnias, begonias, Californian poppy, cosmos, zinnias and marigolds. Impatiens make colourful gap fillers for pots and borders and are especially useful in part shade.

If you want to enjoy this season's planting effort for many summers to come, perennials and flowering shrubs are the way to go. In the shrub department consider hibiscus, vireya rhododendrons and repeat flowering roses such as the easy-care Flower Carpet range.

Salvias offer some of the most stunning blues, intense reds, and all the shades in between. Mexican bush sage, Salvia leucantha, grows about a metre tall and wide with velvet textured flowers of violet rose, a colour which contrasts superbly with golden helianthus. Salvia 'East Friesland' produces rich violet blue flowers on a bushy 40 cm plant. Another tall blue sage, Salvia mexicana grows anywhere between 1.5 and 3 metres high. Its flowers range from blue to purple, striking with their bright lime-green calyces. Bright blue Salvia farinacia is a perennial which can be cut back to flower a second season, but most often grown as a late summer annual. With a few exceptions, salvias thrive in full sun and well-drained soil. Most are easy to strike from cuttings.

Also excellent in the cool colour range are the Asters with their tall daisy smothered stems. Agapanthus can't be ignored if you want a tough plant in blue, but need space to themselves. They'll too quickly take over unless you partner them with other toughies such as cannas or red hot pokers.

Hot colours are well catered to by the likes of Canna, Coreopsis, Crocosmia, day lilies Helenium, Helianthus, Hibiscus, Pelargonium, and Rudbeckia, and not to forget dahlias, which bloom with flamboyant generosity from high summer through autumn. Look out for New Zealand breeder, Dr Keith Hammett's new age dahlias with their naturally compact growth and attractive lacy foliage.

There is much to be gained by experimenting with a wide range of different flowers, but keeping the list short while repeating clumps of the same plant throughout a garden generally gives the most eye catching results. Aim for a range of different heights, plus a few strong anchor plants such as flax or canna.

At this time of year watering is the biggest concern. Any new planting will require regular irrigating. However, once they get their roots established, many plants are surprisingly tolerant of dry spells. Improve moisture retention by digging lots of compost into the soil before planting and finishing off with a layer of mulch - a must at this time of year. Be sure to water thoroughly, so that the water penetrates deep down into the soil and encourages strong downward root growth. Light sprinkling promotes shallow roots vulnerable to drying out.

Keeping flowering plants in peak performance is all about feeding, watering and regularly snipping of spent flower heads.

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