Roses are world favourites and can be spectacular, however the climate in sub-tropical and tropical Australia sometimes plays havoc with them in terms of fungal infection.

Warm, humid summer conditions provide the ideal conditions for fungal diseases to thrive. The two main problems are powdery mildew and black spot.

Powdery mildew appears on new foliage and buds, first as a series of small white spots, which later become a furry mass of mould. It causes the leaves to wilt and wither and eventually die. Black spot shows up on older leaves as dark, circular marks and eventually the foliage turns yellow and falls to the ground.

Both these fungal diseases can severely stress the plant and diminish its performance. Not only will your roses look unattractive, but they will produce a poor show of blooms. So how do we safely get rid of these problems?

When planting rose bushes it is essential to space them far enough apart to allow for good air circulation all round. They should be planted in full sun away from other plants that will smother their stems and compete for moisture and nutrients.

Hygiene is important: clean secateurs with a solution of bleach and water between each bush; never compost prunings; and remove any fallen foliage. It is generally best not to use chemicals in the garden, but choose instead one of the following organic and natural alternatives to stop fungal diseases.
Firstly, you can use lime sulphur diluted with water to the manufacturer's recommendations, and sprayed over the stems and trunk. Apply this in the winter when the plant is dormant.

Secondly, some organic growers have used milk and baking soda successfully. Simply mix half a litre of milk with two tablespoons of baking soda in five litres of water and spray liberally over foliage and stems. Apply at any time of the year.

Thirdly, use SeaMax® Fish & Kelp, which not only prevents fungal disease, but also fertilise your plants at the same time. Professional rose growers have been using this excellent product for years with superb results, and it is now available for the convenience of home gardeners.
Rose Growers love it so much that SeaMax® Fish & Kelp is now endorsed by The Qld Rose Society.

So, if fungal diseases attack your rose bushes, and you want a safe, easy method of prevention, simply prune back the affected areas and apply SeaMax® Fish & Kelp.


Happy Gardening with Searles from the Searle family.

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