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8 Jan 2019

Top summer gardening tips

January is still a busy time in the garden, but all the great work done in spring preparing for summer is now paying off. Like us, many plants struggle with Sydney’s hot humid summers. We asked our Horticultural Supervisor, David Laughlin, for some tips and tricks that you can apply to your own garden this summer.

The horticulturists at Centennial Parklands are busy watering and weeding over the past few weeks. This spring was particularly good for plant growth - including weeds too. Right now, there are many weed seeds in the ground waiting to germinate.

Keeping weeds under control before they set seed saves a lot of work in the future. If you don’t have time to remove a weed completely at least remove the flowers before they drop their seeds.

The horticulturists at the Parklands are targeting weeds like Paspalum (crown grass), Conyza canadensis (Canadian Fleabane) and Ageratina adenophora (Crofton weed) which should be controlled now before they set seed.

centennial park, horticulture, summer gardening, sydney
Flowers are blooming across Centennial Park.

Rose Garden prep work


Our Rose Garden also gets some special attention at this time of year. The main spring flower flush is long gone and we want to have the roses in top condition to put on a stunning summer flower display.

To ensure roses are performing at their best, fertilise fortnightly with a liquid feed throughout the flowering season. A fertiliser with a ratio of Nitrogen, phosphorus, potassium such as 8-2-10 plus trace elements will do the job.

rose garden, centennial park
The Rose Garden is still soaking up the summer sun.

What to fertilise 

Also, in the Rose Garden many fungal problems such as black spot are at their most prevalent. To minimise fungal issues a fortnightly spray of ecofriendly Fungicide until April will provide protection. Hybrid Tea roses should have spent flowers and diseased growth removed throughout summer and autumn.

It’s a good time to fertilise Camellias, Azaleas and Rhododendrons to encourage bud development for flowering in the cooler months. There are a few specialised Camellias, Azaleas and Rhododendrons fertilisers readily available. Don’t over use fertilisers as these plants often have shallow sensitive roots which can be damaged by over fertilising.

camellia, centennial park
Camellia close up in full bloom

What to prune

It is also a good time to prune Wisteria to keep unruly summer growth under control. Vigorous regrowth can be thinned which encourages the production of new flower buds. Wisterias flower on older wood so leave about one foot of this year’s growth for next year’s flowers.

Check that your garden adequately mulched anywhere between 50 to 75 mm thick for most plants. During hot windy weather the soil surface can dry out stressing plants. A mulch layer helps to maintain water in the soil and suppress weeds. If you use an organic mulch such as straw or compost this will add nutrients and improve soil health.

There are a few important jobs to be done now but the most important thing is to keep water levels up for plants to help them through the warm summer weather.

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