Common Gardening Problems - I

Black Spot
This is a fungal disease that loves humidity. In Sydney's warm and relatively humid climate, roses often suffer from it. Lisa doesn't like to use chemical sprays so usually she deals with the fungus by removing the leaves.

"I think that's a great solution because as Black Spot is a fungal disease, removing the infected leaves prevents the plant being re-infected.

White Louse Scale

Clustered together on the stems of Lisa's roses are insects which, collectively, resemble white fungi. Angus explains that it's White Louse Scale. This is a sap sucking insect that should be removed immediately because numbers can build up quickly. Angus suggests rubbing them off with an old toothbrush. If the problem persists, spray them with a horticultural oil, such as White Oil, which is safe to use in the garden.
Spider Mite
Lisa grows a few standard roses in pots. To dress up the base of the roses Lisa's planted strawberries. The roses look great but Lisa points out that many of the leaves are discoloured. Angus says the discolouring is caused by a fungus and is an indication of another problem, Spider Mite, which lives under the leaf. These pests are extremely small but can cause a lot of damage. They are sap-suckers and reduce the ability of a leaf to withstand other pests and diseases, which is why fungi are also attacking the leaves. Angus suggests that, once again, the best remedy is to remove the affected leaves and throw them away.
Strawberry Runners: The strawberry plants Lisa is growing in the rose pots are producing long runners. Angus says, "This is the way strawberries naturally propagate, but there's no room for them in the pots therefore the runners can't set down roots. They are merely pulling energy away from the strawberry flowers and fruits, so the best thing to do is pinch them off as close as possible to the base of the plant. That'll keep the plant fruiting well."

Unsightly view: Most elements in Lisa's garden fit together harmoniously but a neighbouring shed is unsightly. Lisa has tried to overcome this problem by planting a row of camellia sasanquas against the fence but she does not feel they're growing quickly enough. Angus suggests liquid feeding during the camellia's growing period, which is spring. "You could also liquid feed the foliage with a weak solution of liquid fertiliser. Also, trimming the front of the plants will encourage them to grow upwards. I think you could cover that area within a year or two."

Source: http://www.abc.net.au/gardening/