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
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.
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
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.
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 &
Happy Gardening with Searles from the
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JC & AT Searle Pty Ltd
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