This May we have had one of the best seasonal rains to start our autumn winter period with many people being rewarded around our large state with good rainfall. Our orchard and gardens have certainly benefited from this early rainfall as have our farmer friends up in the wheat belt with seeding operations now finished and grass growing well for all the graziers. So let's hope our ole mate Hughey keeps sending it down.
We have had some great garden visits this year and the club is going through a great establishment phase with many new members.
If you want an article included in the monthly newsletter, please contact me or other members of the committee and I will have it included in the July issue.
Also in our member group there must be a reader who can possibly help the RFC WA develop a logo for our cover of this mag. If you think you could be the Fairest and Best at Design, then please contact members of the executive.
Remember to wear your PPE at all times as there are quite a lot of home injuries from secateurs and other garden implements reported in WA. Also if you are using potting mix, please wear a face mask and gloves to prevent Legionnaires' Disease.
What to do in the June Orchard.
Now is a good time to plant olive trees if you can purchase the correct varieties to grow in your orchard for your area. Ask yourself why you want to plant an olive tree, as you know olive fruit requires pickling before you can eat it, or do you want to make your own olive oil? Wow, so many choices for you to make before you plan your olive tree area.
If you want to grow an oil variety in your orchard you can plant the following:
Frantoio is an old Italian variety with about 20% oil. The tree is a moderately vigorous tree with dense foliage and produces oval-shaped fruit which weigh about 2 grams.
Leccino is a smaller tree and has about a 16-20% oil yield. The Leccino will need a pollinator which can be a Mission, a Frantoio or a Pendolino.
Pendolino has a weeping habit, the olives are smallish with about 15-17% oil content.
Mission is my favourite as it is a dual purpose tree and can be used for pickling and oil production. It can grow too large and will need to be cut back to size so when you harvest the fruit they are accessible.
Verdale is another dual purpose fruit with an oil content about 18-20% and is smallish at maturity.
Olive trees for pickling:
Kalamata, a Greek olive is very good.
Mission and Verdale are also great for pickling.
Manzanillo is good for pickling green olives.
Sevillano, an olive from Spain is great for green pickled olives. You need to keep this tree under control as it can grow tall.
Barouni is a North African variety which produces large fruit up to 10 grams in size. The tree is a very good spreading specimen. I only have one of these trees in my stable and have not let it fruit as yet.
Barnea is an Israeli variety and can be a dual-purpose fruit, for pickling and oil.
UC13A6 is from the University of California with large, almost roundish fruit.
An answer to a question about figs not fruiting probably means that cross pollination is not occurring in your orchard. It's best to choose a self-fertile variety when buying a fig tree, as this should help alleviate problems of no figs or very few. All the commercial varieties of figs in WA do not require pollination – they set parthenocarpically. Popular varieties are Black Genoa, White Adriatic, Brown Turkey, and Cape White.
How many growers use white-out to protect fruit trees from sun scald and pest attack? White wash or lime and water mix or hydrated lime has really been the traditional method to paint the trunks of fruit trees. It helps to reduce or prevent heat scald from the sun especially when trees are out in the open and when fruit trees and shrubs are quite young.
It also stabilises the sap temperature in tree tissues. It can help to increase fruit yields by protecting the bark, and helps to protect from mould and fungal disease that can attack your trees during the year. The white wash can help in preventing some insects hibernating in the bark.
If you try this mixture on your trees it is important to remove any loose bark and dirt from your trees. You can use a water-based paint of 50% paint and 50% water, and the best time of the year is late winter just before the insects that attack the trees are really active, to prevent damage to the tree. Oil-based paints are not good for your trees, in fact they can kill them.
Nectarines and peaches now need to be sprayed with copper sprays to prevent leaf curl. Leaf curl is an insect problem but copper sprays are antifungal. It is a great time to spray as some trees still have leaves. The leaves that fall onto the ground will contain traces of copper spray which will incorporate into your leaf litter which is ok. Make sure you have another couple of follow up sprays before bud burst.
Prune your nectarines and peaches now if you didn't prune in summer after your fruit trees finished fruiting. Fruit is borne on last season's wood; thin these out to reduce height for better canopy management, making it easier to harvest. Reduce the vigorous laterals from the main frame work by half to produce better fruit and remove overcrowding laterals.
Fig trees have now finished their autumn fruiting so prune these fruit trees, as they need to be thinned and pruned to shape. Don't allow your fig tree to get too large as you will never be able to control fruit picking or any diseases. Also remove old dead or diseased wood.
Order your stone fruit trees now, as bare-rooted trees will soon be available at your favourite Nursery.
Remember, foliar applications of micro nutrients in citrus are best absorbed when new leaves are about half-to-three-quarter full size. Mature leaves do not readily absorb nutrients.
Soft Pink Scale
This picture is of a fig leaf from a tree that is about 10-years-old situated in Perth's southern suburbs at Murdoch. The leaf has been attacked by a small scale insect that that is a sap sucker with a waxy covered scale that is attached to the body of the insect. The mouth parts pierce the phloem and excess fluid is excreted as honey dew, which attracts ants and provides a growing medium for sooty mould. Eggs are laid in a waxy sac or under the body of the female. Female soft scales have two or three immature instars and the males have four.
Predators of scale include lady bugs, parasitic wasps and lace wings.
Eco oil, pest oil and Neem oil seem to be reasonably effective but should be repeated at least three times for best results. It is important to attack these scale insects as soon as you sight scale on your trees and bushes.
Other Garden problems from readers.
I always seem to get many questions about lemons, and at this time of the year, citrus splitting. Citrus splitting comes about mainly with younger trees in autumn. Navels are the worst, or more susceptible, at splitting although I have seen some mandarins and tangelos split as well. It mainly comes from temperature and rainfall fluctuations that we experience at this time of the year especially late March, April and May.
Another possibility can be with a dry and warm start to spring in early September which happened last year, and your irrigation equipment was not working efficiently and most people had not composted around the shallow root system of their citrus, which became scorched from the sun.
I recently visited a property which I believe exhibited boron deficiency in the fruit. Boron deficiency can sometimes be seen in our poor sandy soils in the Bassendean sands area. It is important to apply boron to the soil, which can be purchased from any friendly nursery, or by applying about 30-40 grams of borax to each tree; it's important then to water this in immediately after applying it. The affected fruit had a brown staining under the skin and the flesh was also very dry. Looking at the leaves, thick veins can be seen. Leaves sometimes split and can also curl under, and the leaf colour can be a yellow-bronze colour.
The citrus leaf miner mostly comes out in the warmer months around August and September, although I have seen some damage left by these insects recently. The citrus leaf miner is actually a tiny moth which lays its eggs on the top of the new leaves of citrus trees. The small grubs hatch out and feed by burrowing into the leaf leaving a telltale silvery trail. The leaves then become twisted and turn up, so this can be seen quite easily when checking your citrus trees.
Sadly young citrus trees don't cope as well as older citrus trees because there are less leaves which mean there is not enough leaf area for photosynthesis to work properly. For control use white oil with maldison or use neem oil on new growth. If an oil, penetration is minimal. Usually oils work by suffocation. If neem oil has other active ingredients added, then these may be absorbed. Infected leaf on the left side of the pic.
The Sapote Family
White Sapote or Casimiroa Edulis.
This tree is a native of the Mexican Highlands and can be grown throughout the Perth metropolitan area. It is from the Rutaceae family which also includes the Citrus family. It can be a large tree up to 8 metres high: best to grow only grafted trees. The trunk of the tree stays green on young trees and the flowers are quite tiny, greenish-white in colour and are borne in groups of twenty to more than a hundred. They are produced in about February or early autumn and fruit is ready in early April and May.
I have seen the variety called Golden Globe growing on a property near Wanneroo which has adapted to the white sands in that area and has produced prolific crops of fruit in the past two years. Another variety suitable for growing in W.A is the Lemon Gold variety, and some nurseries are selling trees as White Sapote and are unnamed and possibly seedlings.
Sometimes the fruit is susceptible to fruit fly and the fruit, when ripened, can be bitter and not always sweet. The fruit will not last more than a few days, which is the main reason it is usually unavailable at super markets (but more likely to be found in fruit markets). It is often called “Aztec Fruit”.
I have a tree on the estuary which is 3-years-old and only 1.2 metres high. It has not flowered or fruited, but from sampling one in a friend's fruit bowl I think this is a good choice in your back yard orchard. Plant your tree in autumn and use dolomite, as Sapotes needs magnesium, so use 2kg per tree. Chicken manure is an excellent fertiliser for a sapote. NPK is also advised at a rate of about 250grams per tree per year of age. Have fun finding this tree at nurseries and good luck.
Flowering Pattern of Avocados
The flowering patterns or the sex life of an avocado was once said by an esteemed horticulturalist as protogynous diurnally synchronous. A huge mouthful to the average gardener, but that's the story of how an avocado sets fruit. Avocados have complete flowers, this means they have both male and female parts, but a single flower is female only for a period then becomes male only for another period – (protogyny means female before male)
Type A avocados
Flower functionally female in the morning of day one, then functionally male in the afternoon of day two.
Type B avocados
Flower functionally female in the afternoon of day one, then functionally male in the morning of day two.
This means if you are growing avocados in tropical and sub-tropical areas where the temperature is a consistent 20-25°C you will need two trees, a Type A and a Type B tree to set good fruit, as different varieties flower at different times. In a sub-tropical climate such as in Perth you will not get the consistent temperature of 20-25°C that favours the flowering patterns above. The consequence of this is that in both Type A and Type B varieties the patterns alter, resulting in some flowers being in the male phase at the same time as other flowers are in the female phase on the same tree. This is good news for sub-tropical areas as it means you will get adequate fruit set from a single tree. Also multiple grafts with different varieties that flower at similar times can help.
Avocado varieties in Group A:
Reed. This is the cannon ball avocado and can weigh up to 500 grams. It is an elegant tree and grows taller than it is wide, has a tolerance to Phytophthora and comes from Guatemalan rootstock.
Wurtz. This is the smallest-growing of all avocado trees and is suitable to grow in a pot. It has a weeping habit.
Pinkerton. A medium-spreading tree which is sensitive to frost and has green slightly rough skin pear-shaped fruit.
Hass Hass has dark green skin, the fruit is pear-shaped and is the most widely grown variety in WA. It can also be grown on Guatemalan rootstock
Avocado varieties in Group B
Bacon. It is suitable for cooler regions, is a majestic shade tree and has moderate tolerance to frost, with pear-shaped smooth fruit.
Sharwill. A medium-spreading tree with pear-shaped fruit.
Sheppard. Is a medium-spreading tree with green pear-shaped fruit with smooth skin.
Fuerte. A large spreading tree with pear-shaped fruit and has good frost tolerance.
Having been to a few local orchards in the past month I have seen nutrient deficiencies in most citrus groves or properties growing citrus trees. Citrus are really heavy feeders and are susceptible to nutrient deficiencies, especially citrus growing on our Bassendean white soils with a low pH.
It is very important to test the soil pH in your back yard orchard and gardens at least twice a year. These kits can be purchased from most nursery centres and some hardware shops.
For every one point movement in the scale, the number of hydrogen ions changes by ten times. So a pH of 5 and a pH of 6 may be only one point different, however, for example, there are ten times more hydrogen ions at pH 5 than there are at pH 6. Many soils in Western Australia are low in pH and as a gardener you must increase your pH to 6.5 for your citrus to produce quality fruit from a well-grown tree.
From looking at the trees, I believe most home orchards are deficient in magnesium or Mg. At first magnesium deficiency is really seen in older leaves on your tree. They will have a yellow midrib and blotches will then increase till the whole leaf is yellow except a green triangle at the base of the leaf. This is because magnesium is a constituent of chlorophyll and the plant moves the chlorophyll from the old leaves to the new leaves.
I like to add two or three handfuls of dolomite to the trees, or you can use Epsom salts, which is magnesium sulphate, around the tree and water this in with about 20 litres of water. Growers have also used 20 grams of Epsom salt to one litre of water and sprayed onto the leaves of the tree.
Hakea laurina or Pincushion Hakea. In autumn and late summer we have many native shrubs and trees flowering, and in the past few issues I have included many local shrubs that are indigenous to the near-Perth areas. A small tree that grows to about 8 metres is Hakea laurina or Pin Cushion Hakea, which is now flowering and is a magnificent bush flower that attracts bees by the hundreds. The flowers are 70mm across and are a reddish pink in a ball-like cluster. This tree is a native to southern Western Australia and is a must if you have room in your garden for attracting bees. It is easy to grow and should be on your Christmas shopping list from Santa.
This item was sent in by Barry Madsen, from his winter retreat in FNQ.
Dragons up North - Pitayas or dragon fruit as they're commonly known belong in the genus Hylocereus and are tropical climbing cacti with triangular stems in cross section and numerous small black seeds dispersed throughout the soft flesh. The picture shows the red-fleshed species, H. monacanthus (730g), which doesn't have spines. H. undatus is similar in size and external features but has white flesh, while H. megalanthus (260g) has yellow skin and very sharp spines which are easily brushed off when fully ripe. All three types are most simply eaten by spooning out the flesh. When dried, the flavour is even more concentrated and becomes irresistible. As the picture suggests, the two spineless types are the largest of the three. I have a number of these plants in North Qld and they largely look after themselves without any hand pollination being necessary. Always a good haul when we arrive here in late May each year.
--- Barry Madsen
Next Month: Environment
Native Bees in Western Australia
Honey Bees in our garden
Pests and Diseases in our Orchards
Bio security in your Home Orchard