Gardens are best given a couple of deep waterings each week rather than a little sprinkle each day.
Gardens are best given a couple of deep waterings each week rather than a little sprinkle each day.
We are now enjoying some consistent summer weather. Overnight temperatures have remained in the higher teens in the past couple of weeks and this is good for plant growth - as long as plants have a good supply of water.
Soil moisture levels in our city are dropping and gardensare starting to get very dry in lighter soils particularly.
In January, Whanganui had 5.4mm of recorded rainfall and as we venture into February there is little in the forecast at this stage. This contrasts to 20.8mm last year and a historical average of 53.1mm. Regular wind is further amplifying the drying effect in the garden.
Irrigation and watering will strongly influence the beauty and success of the garden in February and into March.
We are very lucky in Whanganui to have an excellent water supply that does not rely on rainfall. This enables gardeners to water all year round without the restrictions that are common in some areas of New Zealand.
At this stage of the summer I recommend a walk around your property to check on the health of the plants in your garden, particularly looking for signs of water stress.
Gardens are best given a couple of deep waterings each week rather than a little sprinkle each day.
This method of watering encourages roots to search deep for water rather than remaining close to the surface in expectation of another light sprinkling.
Larger shrubs and trees will benefit from a hose left on drip overnight and shifting the hose around the property each morning is a good strategy to keep your plants healthy.
Soaker hoses (a porous type of hose, where water seeps through the hose) are also highly effective as they deliver water directly to the soil.
Soaker hoses (a porous type of hose, where water seeps through the hose) are also highly effective as they deliver water directly to the soil.
The hose can be weaved through a garden bed underneath the desired plants where the water is delivered directly to the roots of the plants.
This method of watering reduces the amount of water on the leaves. Water on the leaves, particularly at night, increases the risks of fungal diseases such as mildew. The best time for watering the garden is early in the morning.
Applying mulch to the soil during the summer season will help to conserve moisture and to keep the soil cooler; it will also reduce weed growth and can make the watering you do more effective and longer lasting. It is best to apply mulch after the garden area has been thoroughly watered.
During February in our late summer period, many gardens reach their full beauty.
Bedding plants are at their best and brightest and the orange and yellow marigolds and the various colours of petunias, lobelia and geraniums brighten many a border, pot or container and hanging basket.
Another flower at its best is the tropical impatiens with its bright red, pink and white flowers making a stunning display.
Summer lilies release a fragrance that makes the air heavy with a sweet scent, English lavenders and a number of roses will produce another flush of flowers and grace many a garden with a blaze of colour.
Agapanthus are currently looking stunning, as are the summer flowering gum trees (eucalyptus ficifolia) that are currently flowering around Whanganui.
Often at this time of the year gaps can appear in borders.
Planting a selection of perennials that flower later in the summer will help keep the borders bright over the next couple of months.
Plants to look out for include salvia, chrysanthemum, rudbekia, echinacea, dahlia and alstromeria.
Climbers, such as clematis, honeysuckle and pandorea, envelope fences and scramble up pergolas, trellises and over arches, to offer privacy and seclusion.
Roses require attention at this time. Spent blooms should be removed at regular intervals during the flowering season, not only for the tidiness of your plants but also to prevent the formation of seed heads which wastes the plant's energy.
When flowers or spent blooms are cut, a reasonable length of stem should be removed.
New shoots have generally started to develop on the old flower stem and a clean cut should be made just above one of these. This will encourage healthy growth and more flowers.
If your soil has acidic tendencies or if heavy dressings of organic materials are applied annually, then a light application of lime will be of benefit around your roses.
When feeding make sure the fertiliser contains sulphate of potash – it helps to harden growth and makes the plant less susceptible to disease. Potash will aid flowering and may also help to intensify colour in the flowers. Feed roses using Yates Dynamic Lifter, Novatec or Tui Rose Food.
Keep an eye out for the spread of pests and diseases on roses.
Maintain regular sprays to control aphids, rust and blackspot. A good spray is Combat 3 in 1 for Roses - a combination spray insecticide, fungicide and a natural fish fertiliser with minerals and trace elements.
Remember, ensuring your roses are well watered and fed is your first defence against pest and disease.
February is the first of the bulb planting months. In stores there will soon be season ranunculus and anemones in mixed and individual colours as well as crocus, hyacinths and daffodil bulbs.
They are excellent for borders, garden edges, pots and tubs as well as great to grow as a cut flower. More about bulbs in the coming weeks!
Have a good week.
•Gareth Carter is general manager of Springvale Garden Centre
