Saturday, 25 March 2017

Wasps and All Things Citrus


Pests of Citrus-Citrus Gall Wasp

If you though that all you had to contend with on Citrus, was the curling, silvery leaves, the Bronze-Orange stink bugs, the citrus scale on the trunk, then think again, because there's at least one more.
Citrus Gall Wasp-image Dept. of Ag. W.A.
This is a native pest of all citrus, which does include native citrus trees like finger limes, and now is the time when you can notice the damage that this pest has done to your tree. As in a other citrus pests, the damage is done by a tiny moth, about 2-3mm that usually comes out late in the evening and then promptly dies after a very short time.
The damage starts of green and then over time, turns to a grey-brown coloured lump.
The lifecyle of the wasp larvae is quite long, from when the wasp stings the branch and lays its eggs to when the wasp emerges, is about one year.
Initially, you may not notice the bumps, but from Autumn onwards, they are becoming much more noticeable on the citrus trees.

Let’s find out what can be done about this problem
I'm talking with Steve Falcioni, General Manager of
Citrus Gall Wasp damage-image Dept. of Ag. W.A.

We certainly imported a few citrus pasts in the short time that white Australians have been here, but this pest is a native that mainly only attacked finger limes.
Originally only being found in Queensland and northern NSW, but with all the movement of plants from state to state, this pest can now be found as far south as Melbourne.
If you have any questions about Citrus Gall wasps, drop us a line to or write in to 2RRR P.O. Box 644 Gladesville NSW 1675.


Lemon Grass or  Cymbopogon citratus is in the Poaceae Family
Lemongrass is a perennial grass native to tropical southeast Asia.
You may have heard of lemongrass and even seen it sold in the fruit and veg section of the supermarket, but what you may not know is that there are two main types of lemongrass.
There’s East Indian, Cymbopogon flexuosus , and West Indian, Cymbopogon citratus.
In India, it’s used as a medical herb and for perfumes, but not used as a spice; in the rest of tropical Asia (Sri Lanka and even more South East Asia), it’s an important culinary herb and spice.

What does it look like?
Lemon grass grows in a bushy like clumps to 1 m tall with long narrow pale green leaves.
The slender stalks are about 30cm long and are rough to the touch, especially the leaf blade edges which feel quite sharp.

The common name gives it away but lemongrass has a wonderful lemony scent and taste because of the citral , the aldehyde that gives it the lemon odour. 
It can be easily propagated by division and when you pick the Lemon Grass to use in cooking or teas, cut off the bottom part leaving just the roots - put this piece into a glass of water and it will shoot very quickly.
You can then replant it and you’ll definitely always have Lemon Grass in your garden.
For companion plant aficionados, growing a clump of Lemon Grass in the vegetable garden has a good influence on all the plants around it and the vegetables will be much more flavoursome.
Bit a hint on planting that later.
Lemongrass is adapted to hot wet summers and dry warm winters, is drought tolerant and will grow on a wide range of soils but prefers rich, moist loams.
It dislikes wet feet but it does like regular watering in summer.
If it’s damaged by frost in cooler areas, the tops should not be cut until all danger of frost has passed.

How to control that lemongrass.

Cut back the old leaves in early Spring to strengthen the bush as well as tidy it up because invariably if it has dried out , there’ll be plenty of dead stalks which aren’t much good for cooking.
This helps to protect the centre of the plant from further cold damage. 
A listener wrote in asking “How do I go about returning my massive clump of lemongrass to a manageable plant? Or should I dig it out & start off again with a new seedling & keep chopping at it to keep it under control right from the start or in a pot?”

It’s been said about lemongrass, that you need a whip and a chair to keep it under control because left to its own devices in the garden bed, lemongrass really isn't manageable.
You need a pretty big pot to contain it.
In a small pot, it gets too cramped too quickly and as I’ve discovered, get little green growth and lots of dead leaves.
You can divide the clump, but it will soon be just as massive as it is now.
It's jolly hard work digging it, and every single piece with roots on it will in no time flat be just as big as the parent.
TIP:So putting it in the vegetable garden will only work if you contain it in perhaps a bottomless pot.
The leaves can be picked at any time of the year and the stems can be used fresh or dried.

So why Is It Good For You?
Medicinally Lemon Grass can be drunk as a tea as can taken either hot or cold.
Iced Lemongrass is a mild sedative.
Try it for your insomnia, or when you are under stress, or even if you need help to calm a nervous or upset stomach.
The herb is also said to relieve headaches.
Lemon Grass tea in summer is not only extremely refreshing but it’s good for the skin as the oil contains Vitamin A. 
Cooking with Lemongrass
For cooking use the stalks only and pick the thick, light green ones that feel firm and aren’t dried out and wilted.
Cut off the woody root tip of each stalk until the purplish-tinted rings begin to show and remove the loose, dry outer layer(s).
Also, if the top of the stalk is dry and fibrous cut this off too.
When using it in cooked dishes, bang it with a cleaver to bruise the membranes and release more flavour.
Put a handful of the leaves into the saucepan when steaming or simmering chicken or fish to give a delicate but delicious taste of lemon.
It can be used in many dishes as a substitute for lemon.
To store fresh lemon grass, wrap well in clingfilm and refrigerate
This will keep for up to three weeks.


Autumn Gardening Series Part 1

Autumn gardening –is a favourite time for many gardeners around Australia because it’s a much milder time of year compared with the heat of Summer.
In some districts the leaves on deciduous trees are starting to change colours to Autumn buttery yellow tones, or flame red, other plants are putting on a new flush of growth and budding up for the last hurrah before the cold sets in.
Bodnant Garden, England photo M Cannon

During Summer, many of us stayed indoors under the fan or in the air-conditioning while the plants in the garden sweltered.
So, if you haven’t already gone out to assess your plants, you need to act soon
Let’s find out why. I'm talking with Glenice Buck consulting arborist and landscape designer from

Even though some of your plants were being attacked by various pests and diseases, the heat of Summer has meant it’s been too hot to spray with anything because of the risk of burning the leaves.
Also,Summer rains in some districts would’ve meant that the sprays would’ve been washed off anyway.
So over the next few months, seize the opportunity to follow Glenice’s autumn gardening plan.
Glenice says 
" I firstly weed out all beds then I look at what shrubs and perennials need cutting back or deadheading.  Sometime shrubs have grown out of shape or spread out too far across or over other plants prune these plants back into their own shape.  Give everything their own space.  If there are plants not looking healthy try and investigate reason why – it may have a pest or disease it may have dried out through summer."


Native Holly
Alcornea ilicifolia

The holiday season is over but in case you thought you can improve on next year’s celebrations, what about planting something that is reminiscent of this time of year and it’s a native.
Not only that it good for little native birds because of it’s dense foliage.
Let’s find out about this plant.
I'm talking with the plant panel: Karen Smith, editor of Hort Journal and Jeremy Critchley, The Green Gallery wholesale nursery owner.

This plant would discourage intruders if you planted it under your bedroom window or along the front fence line.
Remembering of course that there are 17 plants called native holly in Australia so do ask for Alcornea ilicifolia.

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