All diseases and pests will result in disfigurement or loss of fruit, and damage or eventual destruction to the plants.

Green shield bugs are small green beetles about the size of a fingernail. They get their common name from the shape of their back. Some have a darker blackish-brown path at their base. They can often be seen on leaves and fruit, particularly in the middle of the day.

Tomatoes can be particularly affected, but beans, melons, squash, grapes and capsicums are also attacked. In common with bronze-orange citrus bugs, which are much larger, green shield bugs emit a foul-smelling odour when they are disturbed or crushed. This odour is meant to deter predators from attacking them, and can send a warning to other bugs in the area.

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Green shield bugs appear in gardens from early spring through to autumn. They pierce leaves, stems and fruits with their strong mouthparts and then suck out the sap and juices. As a result of this damage, plants may wilt and fruits may rot.

Adults lay eggs in clusters on the undersides of leaves. The eggs will be arranged in rows. Small nymphs hatch from the eggs and are often black or dark brown, with small red and yellow markings on them. Maturity into adult beetles is reached in 4-5 weeks.

Locating the pests can be difficult. Adult shield bugs can either be picked off leaves and fruit or knocked into a container of soapy water. Early morning, when the bugs are sluggish, is the preferred time to attempt to catch them. They are able to move much faster in warmer temperatures.

Some of the bugs that are caught can be squashed and placed under plants as a deterrent to other shield bugs. Other bugs may lie on the ground as if they are dead. Placing some sheets of newspaper under the plant before squeezing one should enable the others to be collected and disposed of.

Removing eggs from the undersides of leaves will help to control numbers, but catching the adults will also be required.

Passionfruits are one of the main flavours added to summer desserts. They are suitable for growing in this area, provided they are not subject to heavier frosts or extended dry periods. A position of full sun is preferable.

Good air flow is important, although passionfruit plants do not fruit as well if they are subject to strong winds.

Adding plenty of organic compost to the soil prior to planting will help to ensure a free draining position.

Where plants are to be placed into areas of heavier clay, mounds of soil mixed with compost can be created and the new plants placed into the mounds.

Passionfruit plants will grow vigorously. As the plant commences its fruiting cycle, the plant system will become quite heavy, so they should be placed near some support, such as a fence, trellis or pergola.

Provided passionfruit plants have been given ideal growing situations, including a good supply of water, but avoiding extended periods where the soil is waterlogged, they should produce two crops each year, with the first crop usually appearing about 18 months after planting.

Fertilising should commence at the end of summer and also at the end of winter, using a good quality, soluble fertiliser that can be sprayed onto the leaves. Fertilising should be repeated fortnightly.

Once fruits form they generally take about 3 months to become ripe. The ideal situation is to allow the fruits to ripen fully on the vine. They will fall to the ground when they have reached maturity. However, fruits can be picked earlier and ripened indoors, should factors such as extreme weather conditions require this to happen.

Passionfruit vines generally continue to bear for up to five years. After this time they should be replaced by younger, more vigorous vines.

Scale on citrus trees is one of the more common pests that appear now. The gardener may not be aware that the sucking insects have attached themselves to the branches and leaves until they notice a trail of ants on the plant.

The scales exude a sweet, sticky substance called honeydew that is attractive to ants. The ants assist in spreading the scale over the plants in order for them to produce more honeydew.

Honeydew also leads to the appearance of a sooty mould that is actually a black dusty fungus. The sooty mould will soon appear on leaves and stems.

If allowed to remain on a plant, the sooty mould will stunt the plant growth.

Therefore, removal of the scales is necessary for the control and removal of sooty mould.

Small amounts of scale can be removed by scraping the stem and leaves with a toothbrush. However, larger

infestations will require spraying with oil, which will suffocate them.

Make the oil spray by blending two cups of vegetable oil with one cup of pure liquid soap, and mix it until it turns white. Dilute one tablespoon of the emulsion to one litre of water and spray all affected areas thoroughly.

Do this during mild weather, because if it's hot it may burn the plant's leaves.

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