Sunday, 25 September 2016

New Citrus: Key Lime.

Well i finally caved and brought a Key Lime tree today. I had tried to resist the urge as i already have way too many Lime trees already (6x Tahitian, 2x Australian Fingerlime, 1x Kusaie, 2x Kaffir). But i have been reading through the Gardenweb forums lately, and from what a lot of the members there say it is the best flavoured of the Limes compared to a Tahitian. Funnily enough, even with all my Lime trees, i have run out of Limes at the moment! (this is how i have justified the purchase). Must be time to ease up on the cocktails LOL.

Key Limes are smaller and seedier, with a higher acidity, a stronger aroma, and a thinner rind, than that of the Tahitian lime. It is valued for its unique flavor compared to other limes. 

The peel is thin, smooth and leathery, and greenish yellow to yellow at maturity. The pulp is greenish yellow, juicy, and highly acid with a distinctive aroma. They are quite seedy, which are highly polyembryonic (two or more plants identical to the mother plant may be produced from one seed). The name comes from its association with the Florida Keys, where it is best known as the flavouring ingredient in Key lime pie. (Here's my recipe for Key Lime Pie). It is also known as West Indian lime, bartender’s lime, or Mexican lime.

Key Lime is a small, bushy tree that will grow to around 5 metres when fully mature. Its trunk, which rarely grows straight, has many branches, which often originate quite far down on the trunk.  It has slender branches armed with short to medium length thorns.  The leaves are small (
3-9cm long) & ovate, resembling orange leaves (the scientific name Citrus Aurantiifolia refers to this resemblance to the leaves of the orange, Citrus Aurantium). The flowers are 2.5 cm in diameter, are yellowish white with a light purple tinge on the margins. Flowers and fruit appear throughout the year, but are most abundant from May to September in the Northern Hemisphere.


There are various ways to cultivate Key limes. This variety of citrus can be propagated from seed and will grow true to the parent. Alternatively budwood can be grafted onto rough lemon or sour orange rootstock. The method of cultivation greatly affects the size and timeliness of the harvest. Trees cultivated from seedlings take 4–8 years before producing a harvest. They attain their maximal yield at about 10 years of age. Trees produced from grafting or 
cuttings bear fruit much sooner, sometimes producing fruit (though not a serious harvest) a year after planting. It takes approximately 9 months from the blossom to the fruit. When the fruit have grown to harvesting size and begin to turn yellow they are then picked.

The Key lime tree does best in sunny sites, well-drained soils, good air circulation, and protection from cold wind.
Generally, Key lime trees need only limited pruning. Prune only to shape trees, to remove dead wood, to limit tree height & maximise the circulation of air.

Key Lime Pie

Monday, 12 September 2016

How to make Lemon Curd.

There's something about Lemon Curd that makes it so luscious, so delicious. Its a magical mixture of tart Lemonyness, sweet Sugar & creamy Egg yolks that makes it like the Chocolate of Citrus lovers, the ultimate for any Citrus Enthusiast. Made by gently cooking a mixture of fresh Lemon juice, Sugar, Butter & Eggs until thickened, its simplicity makes it even more attractive. Lemon Curd is divine on buttered toast, a simple and perfect way to appreciate the curd's cool, satiny texture. It also makes an easy and delicious filling for tarts, cakes & desserts. Its tart Lemon flavour makes it a great ingredient to balance the spiciness or the richness of other ingredients. Pair it with a Scone or slice of Toast and you'll appreciate how Lemon Curd can transform a simple, somewhat homely item into something wonderful.

Lemon Curd Recipe

250ml fresh Lemon juice, finely grated zest.

5 Whole Eggs

500gm Caster Sugar

100gm Butter, cut into small cubes.

  1. Put the Lemon zest and juice, the Sugar and the Butter into a heatproof mixing bowl. Sit the bowl over a pan of gently simmering water, making sure the water is not touching the bottom of the bowl. Stir the mixture every now and again until all of the butter has melted.
  2. Lightly whisk the Eggs and stir them into the Lemon mixture. Whisk until all of the ingredients are well combined, then leave to cook for 10-20mins. Be careful that it doesn’t curdle by making sure the temperature remains constant, and it doesn’t get too hot. Stir regularly until the mixture is creamy and thick enough to coat the back of a spoon.
  3. Remove the Lemon Curd from the heat and set aside to cool, stirring occasionally as it cools. Once cooled, spoon the Lemon Curd into sterilised jars and seal. Keep in the fridge until ready to use. It will keep (refrigerated) for 1 month.

Sunday, 4 September 2016

Spring Blossoms!

Well its officially Spring! Finally we have made it through the drudgery that is winter. Though the wind, rain & cold still didn't stop us achieving quite a lot of new plantings and enhancements throughout the garden. We put in a new deck for our daily Sundowner, a new Lavender farm of over 60 plants and many new fruit trees and natives. These were all planted in mid-winter with the hope they will be well rooted by the time the dry, parched Summer comes.
With Spring comes the sweet bounty of fruit blossoms and the blossoms of Citrus have to be the most intoxicating of them all. If the flower itself wasn't enough, the perfume they exude is the icing on the cake (especially Oranges).



I usually try to make sure my fruit trees are well fertilised in anticipation of the new growth & flowering that comes in Spring. Early August is a good time to make sure to spread a good Fruit Tree/Citrus fertiliser and even some extra Potash to aid flowering & fruiting. Then when things start to warm up in Spring the plants are all ready to push out their new growth & produce fruit. It is also a good time to spray Copper on the Stonefruits to prevent Peach Leaf Curl. 

Peach Blossom
Spring also heralds the start of the growing season especially for the Vege Patch so I'm also starting to plan what i will be growing this year in there. I will definitely be planting Tomatoes, as far as varieties go i love Cherry Tomatoes so i will plant one red, one yellow teardrop and one black striped Cherries. I also love the Mexican heirloom tomatoes such as Zapotec and other Oaxacan beefsteak varieties that are big, colourful with fluted ribbing and most importantly beautiful flavour. I will also plant three varieties of Courgette, Tomatillos, Jalepenos, Habaneros, Coriander, Basil, Lebanese Cucumbers and Corn. With these i will use them mostly for my mexican-inspired recipes which really shine during summer. For some of my recipes check out my book called 'Viva La Mexico' its available for free download as an e-book at

Tomatillo harvest.

My favourite Summer recipe though has to be my Caprese Salad. Nothing beats a late afternoon Sundowner and then munching this one down with a glass of Rose. Here's the recipe:

Caprese Salad.

Buffalo Mozzarella or Bocconcini.

Ripe Tomatoes.

Basil Leaves.

Extra-Virgin Olive Oil.

Maldon Sea Salt.


1. Slice Mozzarella & Tomatoes into thick, round slices.
2. Pluck whole leaves of Basil.
3. Layer Basil, Tomato & Mozzarella around in a circle.
4. Place a sprig of Basil in the centre.
5. Drizzle well with a good Olive Oil & sprinkle with Salt & Pepper

Thursday, 1 September 2016

Objects of Desire: Sumo/Dekopon

The Sumo is an exciting new hybrid of Citrus with an interesting story. Sadly it is yet to come to NZ in either fruit or tree form but i am very eager to try. From all accounts though, it seems to be a prized fruit at the high end of the Citrus market.

Its story begins in 1972 on Kyushu Island in Japan. A citrus grower there set out to develop a fruit which would combine the best of the easy-to-peel Japanese Satsuma with the big, juicy, sweet oranges from California. It is specifically a hybrid between a Kiyomi Tangor and a PonkanAlthough he saw promise in an obscure tangerine-orange hybrid, this new fruit was challenging to grow. Thankfully, the grower persevered. Over time, he developed a series of methods for growing, pruning and thinning his trees, which is different from all other citrus.
It took over 30 years but his hard work was rewarded when recently, this new variety became the most prized citrus fruit in Japan and Korea.  Following the Japanese tradition of offering the best fruit as a gift, one can find it in Tokyo gift shops, selling for up to US$10 for a single piece of fruit!  Now this legendary fruit, which is called Dekopon in Japan and Hallabong in Korea, is available in America.
Sumo is the biggest mandarin you'll ever seen. It has a distinctive shape with a prominent "top-knot" or large protruding bump on the top of the fruit. The peel is bright orange, bumpy and loose so it peels effortlessly, usually all in one piece! The delicate sections separate easily. Sumo has very little albedo (the white part of citrus), allowing the fruit to section easily with less of the white "netting" sticking to the fruit. It is avalible in stores in very limited supplies available from February-May in the U.S. It's seedless, juicy without being messy, and one of the sweetest of all citrus with very low acid.
At the beginning of the harvest, the fruit is very high in acidity. Consequently growers use a secret Japanese storage method to "cure" the fruit, to reduce its tartness. But with full maturity, after the three weeks curing in vinyl pouches, sugar rises and acidity drops naturally. Dekopons measured 13-18 degrees Brix (a measure of sugar content), numbers that mean powerhouse flavor. (Typically, other commercial citrus varieties such as navel oranges and clementines average 11 to 13 degrees.)
Hopefully this variety will become available soon in NZ. It has only just been released in the US in the past year under the name Shiranui after much cloak & dagger with budwood quarantine procedures from Japan. The Citrus nurserys here i've talked to haven't heard of it yet and have mentioned it is quite difficult to import new budwood into NZ. 


Photos courtesy of Susan Broman and Shizuoka Gourmet

Photo: Oli Studholme

Friday, 26 August 2016

New Citrus: Seville Orange & Lemonade.

This week i spent some time up in the tropical, far north of New Zealand. On the way home i drove through the Orange-growing mecca of NZ called Kerikeri. I thought it might be cool to stop in to an interesting nursery called Flying Dragon (named after the trifoliate orange dwarfing root stock). Most Citrus plants in garden centres in NZ will come from this nursery and they have many interesting varieties. They have several large greenhouses housing all their rootstock plants growing on and then subsequent budding of the various varieties onto rootstocks. Unfortunately they weren't keen on photos sorry:(
Anyhoo i picked up a couple of new Citrus friends to come home with me: a Seville Orange and a Lemonade (aka 'New Zealand' Lemonade for non-kiwis)

Seville orange is a widely known, particularly tart orange which is now grown throughout the Mediterranean region. It has a thick, dimpled skin, and is prized for making marmalade, being higher in pectin than the sweet orange, and therefore giving a better set and a higher yield. It is also used in baking, compotes and orange-flavored liqueurs. Once a year, oranges of this variety are collected from trees in Seville, Spain and shipped to Britain to be used in marmalade. However, the fruit is rarely consumed locally in Andalusia.

Although the Seville orange smells like a true orange, it is quite different. Its rough, thick and bumpy deep orange coloured peel clings tightly to its pale orange translucent flesh, making it hard to peel. The fruit is sour, tart, sometimes bitter and laden with seeds. It is medium size, round, with a slightly depressed apex. It has two primary attributes: the peel contains fragrant essential oils and its flesh, when ripe, is extremely juicy. The tree is attractive, large, vigorous, productive and cold tolerant. It has very few or no thorns. The most common usage for the Seville orange is for the production of marmalade where it can use its peel and juice to its advantage; any sour and bitter flavours can be developed and enriched into elements of depth. Other culinary uses can be to use the zest and juice in flavoured syrups, cocktails, vinaigrette or marinades. Pair with fennel, bitter greens, chicories, olives, other citrus, fresh herbs, aged cheeses, seafood, rice, and Spanish spices. Look here for a great recipe for a Seville Orange Curd Tart or here for Seville Orange Marmalade.
As you can see the Blossoms are large, plentiful and come with the most intoxicating Orange Blossom aroma which wafts throughout the garden, an added bonus to the fruit.
The Seville orange, is also been used in traditional Chinese medicine to treat nausea, indigestion and constipation. The crushed fruit and macerated leaves will lather when mixed with water and is used as a soap substitute in the Pacific Islands. The Seville orange peel, when dried and concentrated, contains a chemical similar to ephedra and has been used in many modern weight-loss products. 

Sour oranges are native to China. Trade routes brought them to Africa and the Mediterranean. This variety was brought directly to Spain by Arab conquerors in the 10th century from northern Africa via Morocco. Cultivation of sour orange varieties led to the Seville orange of Seville, Spain in the 12th Century, where it would accrue its name. The Seville orange was the only orange variety in Europe for the next 500 years. It was also one of the first citrus varieties brought to the New World where it was naturalized in the Caribbean, South, Central and North America. When sweet oranges were introduced to America, sour orange trees would begin to shift their role as edible fruit to rootstock. Cross pollination of the sour and sweet orange trees also proved to create bitter fruits in sweet orange varieties which forced farmers to reduce production of sour orange trees.

A Lemonade is a natural crossbread between an Orange and a Meyer Lemon, first cultivated in the 1980’s in Northland, New Zealand. It grows to about about 2.5-3 metres high. The fruit has the appearance and shape of a lemon though it is easily peeled, and easily segmented. It is unusually sweet and juicy and has a sweet effervescent flavour with a low acid content, tasting of lemonade. It is devoid of bitterness and can easily be eaten as a fresh fruit, or squeezed for drinks. The Lemonade tree often has small thorns and can bear a heavy crop each year. Fruit is ripe when light green in colour and is consumed fresh, juiced, with mixed drinks, or used to make marmalades with other citrus. It is quite popular as a backyard tree throughout NZ & Australia, with a only a few small commercial plantings.

Wednesday, 17 August 2016

Backyard Lavender Farm

My wife has been on at me for ages to get rid of our lawn and use it for something useful and I've finally caved and have planted a Lavender Farm! A while ago we visited an amazing Lavender Farm near Queenstown called Ben Lomond Lavender and I've always dreamt of having rows of fragrant Lavender on mass like theirs. Since then I've always had lots of single Lavs planted around my Citrus and dotted around the garden but i think when in rows and properly trimmed, Lavender really shines.
With Lavender, my favourite varietal is "English Lavender" (its common name) or Lavendula Angustifolia (its Latin name). At the plant store you rarely see this one though as the average punter there seems to prefer the Stoechas variety or "Spanish Lavender" which, my friends, is a seriously inferior plant, trust me. The scent & essential oil of the Angustifolia is sweet, light & beautiful, whereas the other lavenders have a resinous, camphor element to their oil which makes it much inferior. 
When deciding on the variety to use we went with "Grosso". For years Grosso has been the world's most extensively grown lavender for oil production. Grosso is a lavandin, in other words, a hybrid between Lavandula angustifolia and Lavandula latifolia. It has intermediate characteristics of both parents, having long flowering stems with multiple lateral branching. The habit of the plant is bushy and rounded with greenish-grey foliage. It is reasonably slow growing at first but by its third year forming a spherical mound of between 40-50cm both in width and height. For us in New Zealand it is a plant that looks great from early January through to March if left to flower untouched. This is often a time when many other plants are suffering with the heat and dry yet this lavender never fails to impress. The flowers still look good in March, even if a little faded. Plants can then be cut back and trimmings and flowers and stems make good compost. Personally i would have gone with Pacific Blue which is an Angustifolia as the scent is just so beautiful but they are a lot smaller plants and the yield of flowers is about 1/3 or 1/4 compared to Grosso. The Grosso plants also look more appealing during flowering in Summer as they have many prolific long spikes of flowers that look great over an extended period. 
The plants i purchased are all fairly young and will take about 2 or 3 years to fully mature but we should see some flowers this summer hopefully. Today i laid out all the plants evenly in straight rows. Tomorrow i will plant the Lavenders in a easy draining pumice/compost growing medium mix in raised mounds over the stodgy clay topsoil. I'll then lay weed mat over the entire area to suppress the grass & weeds. Eventually i'll lay bark over to give a more natural look.

The Plants.
Spacing out the plants. 
The growing medium.

Mounding up in the growing medium.


Thursday, 11 August 2016


Just thinking of the word “Peach” conjures up an image of yellow, juicy, sweet flesh dribbling down your chin in summer. Peaches epitomise Summer fruits. Its hard to think Summer even exists at the moment, being in the dark depths of Winter. But i have just being spraying my Peach trees with Copper this week and it got me looking forward to this years bounty. Peaches are a tree well worth growing for its delectable fruit, the Peach is also a truly beautiful flowering specimen, with its blossoms bursting into ‘pinkness’ in the early spring which are as good as many Cherry Blossoms. And, being a deciduous tree, it will also produce beautiful autumn foliage after the fruiting is over. I have the below four Peach trees at home; two dwarfs, one full size (Golden Queen) and one in a pseudo espalier (Blackboy). With the full size tree i will have to work hard to shape & prune it over its years as they can grow into being massive trees. Its already is getting quite large and i wish i had pruned him down lower to the ground initially as i will probably now need a ladder to harvest the fruit. There is some great videos here from Dave Wilson Nurseries about pruning with Back Yard Orchard Culture in mind (i.e.: keeping trees at home at a manageable size).

Photo: Scot Nelson
Peaches do need a bit of care throughout the year to combat the dreaded Peach Leaf Curl. Peach leaf curl is a disease caused by fungus. It affects the blossoms, leaves, and shoots of peaches and nectarines, and is the most common disease problem for backyard gardeners growing these trees. The distorted, reddened foliage that it causes is easily seen in spring. When severe, the disease can reduce fruit production substantially.
Peach leaf curl first appears in spring as reddish areas on developing leaves. These areas become thickened and puckered, causing leaves to curl and severely distort. The thickened areas turn yellowish and then grayish white, as velvety spores are produced on the surface by the leaf curl fungus. Later affected leaves turn yellow or brown and can remain on the tree or may fall off; they are replaced by a second set of leaves that develop more normally unless wet weather continues. The loss of leaves and the production of a second set result in decreased tree growth and fruit production. 
The best way to combat PLC is to spray with Copper Fungicide. I would recommend an early treatment when the tree is dormant in early August. It is also advisable to apply a second spray late in the dormant season, preferably as flower buds begin to swell but before green leaf tips are first visible.

Peach Blackboy

A stunning peach with a dark wine coloured outer and inner. The rich, juicy, textured flesh is absolutely delicious. One of my favourites. If there are any left over after raiding the tree (which I doubt) they also bottle well. Deciduous.
Suitable for warmer areas including Auckland/Northland
Flower Colour: Pink
Habit: Upright & Spreading
Estimate Mature Size: 5m x 3m

Peach Bonanza

A genetic dwarf standard Peach tree that will provide you with a bonanza of delicious juicy peaches in summer. The fruit have yellow skin with a red blush and yellow flesh. With pretty pink spring blossom and lush green foliage this tree is highly ornamental as well as productive. Self fertile. Deciduous. Peaches are tolerant of most soils but they do need good drainage and love to be in the sun. 
Suitable for warmer areas including Auckland/Northland
Habit: Compact Standard
Estimate Mature Size: 2m x 1.5m


Peach Golden Queen

NZ's favourite peach. As the name suggests this is the Queen of peaches with firm, tasty, golden yellow flesh. Great for bottling or eating straight from the tree. Crops well, ripens in late February/March. Cling-stone. Deciduous.
Suitable for warmer areas including Auckland/Northland
Flower Colour: Pink
Habit: Upright & Spreading
Estimate Mature Size: 5m x 3m

Peach Pixzee

This dwarf standard Peach tree is a real little sweetie. With beautiful pink blossom in spring, followed by fresh green leaves and then delectable full size freestone peaches in summer. The peaches are a warm golden yellow blushed red with freestone flesh that is also golden. Happy in the garden or a container. Mostly Deciduous but can hang on to green leaves right through to late winter.
Colour: Pink
Habit: Compact Standard
Estimate Mature Size: 2m x 1.5m

Sunday, 7 August 2016

Common Citrus Diseases & Pests

Here is a list of the issues that i have come across with growing my Citrus over the years. Some you can be pro-active & spray with this or that. I like to be as natural as i can with my plants especially with anything i intend to eat. So i will only spray only if a problem seems to be getting out of control. Also since i have so many fruit trees, to spray them all would take ages to do & be quite costly. I think its very important when choosing sprays to consider the effects on other members of our ecosystem specifically BEES. Please avoid the use of nasty sprays such as Confidor which contains Imidacloprid which is dangerous to our Bee buddies. Using Horticultural Oils such as Neem or Conqueror Oil with, if necessary, added Pyrethrum should be all you need and will be fairly organic. Copper is the only other spray i would suggest for Fungal & Bacterial issues.

Verrucosis or Citrus Scab
Verrucosis or citrus scab can affect all citrus fruit but predominantly Lemons & Limes. It is a very common sight on lemons. Tiny lumps, or wart-like protrusions, appear on the skin of the fruit and leaves. It looks unsightly but the quality of the fruit inside is not affected. If you want picture perfect lemons or lots of zest for cooking, regular spraying of copper is necessary. If you're just after the juice you can let it be.

Blossom-End Rot

Blossom-end rot is due to lack of calcium- either because it's lacking in the soil or there has been drought or irregular watering so the tree couldn't take up enough nutrients to support the growth of the fruit. It is a sign of malnutrition rather than disease and is easily treated - although there's nothing to be done for fruit already afflicted. The addition of lime (a handful or two per tree) around the drip line would be an effective stand-alone remedy, but you might as well cover all bases by applying citrus food too. Citrus are gluttonous plants so proper fertilization and water management help to minimize this problem. Try to avoid allowing the soil to become too dry and then overly wet. Wide fluctuations in soil moisture inhibit calcium uptake and movement.

Sooty Mould
Sooty mold is a fungus, which causes the blackening of the leaves of citrus trees. The mould forms on the leaves as a result of honeydew secretions from insects such as whiteflies, aphids and mealybugs. Insect control is the most effective way to prevent this disease. To control the insects and prevent the secretion of their honeydew discharge, spray the tree with Horticultural Oil with Pyrethrum. When spraying the tree ensure that both the top and undersides of the leaves are adequately sprayed. A second treatment spray may be required about 10 to 14 days later depending on the severity of the insect infestation. 
To control and eliminate the mould growth that has already developed, spray the tree with Liquid Copper Fungicide. Generally one application of Copper is adequate for sooty mould control, but a second application about 14 days later may be required in major outbreaks.

Passion Vine Hoppers
The nymph passion vine hoppers are tiny wingless insects with white fluffy tails that are raised above their bodies like peacock tails. The nymphs and winged adults can jump (hop) when disturbed. From late January on the nymphs go through their final molt and change into the small brown adults that look like small winged moths that are often seen in a queue like line on the stems of plants. The adults will be be active through to autumn laying eggs in small branches of their target plants. As they withdraw their egg laying tube, they pull out small white tufts of plant material which show up as white dots on your plants. 
Control of passion vine hopper is best achieved when the insects are in the immature nymphal stages using Horticultural Oil with Pyrethrum and spray the insects directly. This works by physically blocking the insect’s breathing holes and suffocating them. This would be best done before the nymphs reach maturity and grow wings. Once adults they tend to fly off in clouds as soon as disturbed and they will be difficult to spray with the oil the nymphs can be difficult to spray also, because of their hopping habits.


The citrus whitefly is a tiny white winged insect that is about 1mm in length. It is most commonly found feeding on the underside of the tree’s leaves. When the branches are shaken, the Citrus whitefly will rapidly take flight and can be seen fluttering around the tree. In addition to feeding on the citrus tree, the whiteflies also lay their eggs on the underside of the leaves. When the eggs hatch, the juveniles are small oval, almost transparent larva, which attach themselves to the underside of the leaves and begin sucking the sap from the leaves. As a result, the tree’s leaves begin to curl and appear to be covered with a sticky, sooty mold substance. The Sooty Mould is due to honeydew that is excreted by the whiteflies because they are not able to metabolize all of the sugars contained in the leaf sap. The honeydew becomes an attractant to ants. Over the growing season, several generations of whiteflies can emerge. To effectively control Citrus Whiteflies spray the tree with Horticultural Oil with Pyrethrum. It is hard to achieve full control of the adult flies, but several sprayings of the tree will significantly reduce the juvenile population and in doing so the overall population.


Aphids, when in small numbers, do little damage to a tree, however, under favourable conditions the aphid population can grow very rapidly and cause serious damage to a citrus tree during the growing season. The aphids attack the tree by sucking the sap out of the leaves. The symptoms are very visible on the leaves in the form of multiple puckered marks, yellowing and the twisting of the leaves, which gives the appearance of deformed leaves. As the severity of the aphid infestation increases, leaf drop and twig and branch die back can be seen.
During an aphid infestation, the leaves appear to be dripping sap from the underside of the leaves. This is actually an excretion from the aphids and is called honeydew. The honeydew then becomes an attractant to ants, which feed on it. Ants are known to "farm" Aphids by transporting them up a tree to feed off their honeydew.
Aphids can be controlled using Horticultural Oil with Pyrethrum. The spray should be directed at the undersides of the leaves and other areas of visible feeding and insect concentrations. Normally only one or two spray treatments are required to achieve control. For less severe infections Aphids can be removed manually by squashing or blasting off with the hose.
Lemon Borer
The telltale sign is sawdust exuding from active holes. Other symptoms are that the tree shows poor growth, leaves are dehydrated and branches die. Holes found in branches and sawdust indicates presence of borer. You can spear the lavae with guitar strings poked directly into the holes or spray an product like No Borer Spray Injector into the holes. Remove infected wood where practical. It is a good idea to fill in the borer holes with an acyclic paint. This prevents adults entering the holes and laying more eggs. It also means that it is easy to detect new holes and further problems.
It is a must to avoid pruning between early spring to mid summer in hope that these little bugs will leave your trees alone!

Brown Scale
Scale are brown, hard scale-like insects on woody and green stems. Scale numbers build up in dry seasons, Squash manually or for large infestations spray with Horticultural Oil with Pyrethrum as needed to smother & kill the scale.
Photo:Seabrooke Leckie
Soft wax scale
White, puffy soft scale. Flick scale off manually to remove or spray with Oil if infested.

Slugs & Snails
When Slugs or Snails are present it is common to see holes chewed into leaves and the fruit may be pitted or scarred. You may also see silvery trails winding around the trunk and branches near the soil. Lifting lower branches and inspecting under leaf debris under the tree can also detect snails. A proper sanitation program around the tree is important. Clean-up and remove all leaf debris under the tree. The leaves on the ground become a good breading and hiding place for Snails. In addition place Quash snail bait on the ground around the tree trunk will kill Slugs & Snails on contact & prevent them from migrating up the tree trunk and eating the leaves. Quash is the best as its safe for Pets if they eat it accidentally.

Spider Mites
Leaves go yellow and dehydrated. Minute insects & webs under leaves. Common in hot dry weather, spray with Horticultural Oil with Pyrethrum or Liquid Sulphur spray (But not these two together!)
Leaf roller caterpillar
Leaves tightly rolled and foliage and surface of fruit eaten. Squash manually or for large infestations spray with Horticultural Oil with Pyrethrum as needed.
Mealy bug
Often the presence of black, sooty mould will be the first noticed signs. Small, white, mealy insects found in protected cavities. Squash manually or for large infestations spray with Horticultural Oil with Pyrethrum.

Yellow leaves.
Citrus are gluttons for food. When nutrients are in short supply, their leaves turn yellow and they crop poorly. Feeding with a complete granulated citrus fertiliser will fix most of the problems – or help you to avoid them in the first place – as they provide the nutrients that your citrus trees need. But if you're experiencing problems, take a closer look at the leaves.

Magnesium deficiency: Mature leaves turn yellow, with an inverted green V shape at the base of the leaf, and green on the tips. It's often seen on acidic soils. Applying Epsom salts will correct the deficiency. Dissolve a handful into a watering can of water and water into damp soil.

Nitrogen deficiency: shows by light green to yellow foliage over the entire tree in the absence of any distinctive leaf patterns. With mild deficiency, foliage will be light green progressing to yellow as conditions intensify. New growth usually emerges pale green in color, but darkens as foliage expands and hardens. With yellow vein chlorosis, the midribs and lateral veins turn yellow while the rest of the leaf remains a normal green colour. It may occur with the onset of cooler weather in the winter due to reduced nitrogen uptake by the plant from the soil. Nitrogen deficiency will limit tree growth and fruit production, while high nitrogen applications produce excessive vegetative growth at the expense of fruit production, reducing fruit quality.

Iron deficiency: occurs on young leaves. Light yellow/white leaves and green veins are the signs. It's common on alkaline soil. Treat with iron chelates applied to the soil.