We bought this place about 9 years ago in 1997 – 60 acres or nearly 25 hectares. We’re surrounded by Macadamias and forest. The property was originally pine trees and when they were harvested they left the stumps so we go down a hole every so often. It was also a turf farm prior to when we purchased it and we planted the Avocadoes at various stages. We haven’t topped them as yet but it will happen to retain the view of Maleny and we’ve been organic right from the start. I’m in Biological Farmers which has an offshoot called Australian Certified Organic and we get audited each year so I’ve just certified the middle section with the avocadoes on – not the paddock with the cattle. It’s too hard to control ticks, buffalo fly etc. organically. I also grow 150 bananas but I’m building this up.
Pests and Diseases
We’ve had a lot of trouble with Phytophthora particularly when the trees were young even on this well-drained soil but once the trees get to 3-4 years, you might get small outbreaks but you usually don’t get lethal doses. We treated the Phytophthora just by mulching. 3 years into it, I started to use Trichoderma “Trichoshield” which is a product put out by Nutritech at Yandina. It’s not approved by BFA but you can get permission. The reason is that it is made in India and they haven’t certified the factory there. It controls it to a certain extent but you can see I have 2 trees suffering still.
Sheryl How much, how often and when?
Ross Once a year in August/September just before the spring flush. I buy a kilo and it does the whole orchard and any tree that is suffering a bit, I’ll give it a bit extra. It’s a powder that you dissolve in water then spray the ground. Do it on a wet day or after you irrigate.
Kelly Did you choose Phytophthora resistant rootstock when you bought the trees?
Ross Yes I used trees on Velvic rootstock. I didn’t spray for the 1st three years and I had about 10% loss. ’99 was a really wet winter and that knocked them around so I lost a number of them that year. I have 238 trees but I’m down to 208. The trees that are affected I spray them every 2 months.
Sheryl Phytophthora affected trees can be recognised by their much lighter colour – they don’t have the dark green leaves.
Ross They also lose their foliage. Over winter, you get recycling of foliage but the affected ones almost defoliate completely. It affects the new roots. We get the monolepta beetle and they swarm in the hot summer months. They breed in the bush and they defoliate the young tips and they also get on the young fruit. They don’t do much damage but it just looks bad which means I can’t sell those fruit as 1st grade. They put a scaly mark on the fruit. The year before we had really bad infestations and I sprayed with pyrethrum which is an allowable input. I try not to spray because I think pyrethrum is not selective so it’ll take out the good insects as well so I just did it when I saw the swarming monolepta. Up to this year, we’d get 10-15% fruit spotting bug damage. I can sell the fruit if there’s only 1-2 marks on them but this year, we’ve had 25-30% damage but it’s been a really big crop this year. For the first time this year, we got fruit fly damage; they went in where the fruit spotting bug hit so we got a fruit drop in Feb/Mar. These are the hard lumps. People want organic but they don’t want lumps either! I don’t do anything about fruit spotting bug or fruit fly. I had thought this year of putting traps around.
Sheryl Patrick Nugent looks after an organic avocado farm up at Blackbutt and he’ll be able to tell you all about it.
Ross There are two main outlets for organics: Eco Farms and United Organics and they’re both down at the Brisbane Markets but I tend to sell locally at the Natural Food Store near Buderim.
Sheryl How much extra would you get selling organically?
Ross In recent years people were getting $1.00 per kg and I’d get $3.00 but this year I’m getting $3.50kg for top quality and seconds and smalls $1-$2 kg.
Member Does it pay to go organic for you?
Ross I think my costs are pretty minimal. If you had to use phosphorus acid your costs would be fairly high.
I also give them composted chicken manure and in the compost I also put in banana stems, cow manure, weeds and vegetable scraps (sometimes). I spread the fertiliser twice a year when they were young but it’s now down to once a year.
Sheryl So, you can get organic chicken manure?
Ross No, but it’s allowable as long as it is composted and I also spray it with the microbes. The chicken manure comes from Macdougalls at Chevallum and the company stores it in big heaps and turns it every so often so they call it composted and it’s reasonably broken down.
Sheryl How do you feel the microbes are going here?
Ross I’ve only been using them a very short time so I’m not really sure. Les Nichol a vegetable grower under BFA certification has been using them for a while and he’s having really good results and his soil fertility looks great. I also went to a 3 day biodynamic workshop last year but I haven’t taken it up whole-heartedly but I am interested in some of the concepts. I’d like to learn more about it.
Sheryl Talk to Terry Little, Peter Sauer, Col Metcalf or John Hatch. I also put on gypsum every year too – 1-2kg per tree just before the spring flush. That’s mainly for calcium – it’s certainly not for improving drainage in the soil which is what gypsum is often used for but it’s an allowable as well.
Peter What type of gypsum do you use?
Ross Natural gypsum marketed by QLD Organics.
Sheryl One of our members has bananas that are so high up that it’s precarious trying to bag the bunch.
Ross I use a ladder but I’d like to find out too. If you plant them too close, they tend to grow tall and the bunches can be small – space them out at say 3x4mtr or more.
Sheryl How do you pick your avocadoes up high?
Ross I climb the tree!
Sheryl When I was in Sydney I bought a fruit harvester and got Bob to attach it to a swimming pool extension handle and it worked extremely well in hooking avocadoes high in the tree. If you want one, it comes from Magnamail Q474 Fruit Harvester $12.90 www.magnamail.com.au or ring them on 1800 251 252 Showrooms at 2 William Street Brookvale NSW 9am to 4.30pm Monday to Friday Opposite Warringah Mall. Shop 25, Kiora Mall, 29 Kiora Road, Miranda NSW 9am to 5pm Monday to Friday 8.30am to 12.00pm Saturday.
Ross I planted a shrub legume mainly Leucaena leucocephala – there are other species as well.
Sheryl Isn’t it classified as a weed?
Ross Yes, a lot of people think it is a weed but so are pine trees! Those 4 trees are my seed production block and I’ve let them grow – it will grow into a tree about 10-15 mtrs high but I just keep cutting it back to keep it for the seed and the ones in the orchard I cut back. It’s mainly grown for cattle fodder; high protein content and cattle really like it but so do wallabies and hares so I had to fence it off. Another one I planted was Sesbania which you might find a better species in terms of its available nitrogen content of the leaf and more rapid breakdown of the foliage to provide that nitrogen source. As you can see, I planted the Leucaena between each Avocado tree but now the Avocados are shading the tree legume so the productivity of the amount of material I’m getting from the legume trees is gradually declining and some of them have died right out because they have been completely shaded and they are not shade tolerant so now I have to think of alternatives so I might have to plant a block somewhere which I can cut and bring back to the trees. What I could have done was plant a row down the middle between each row of avocadoes and then you cut with a forage harvester but I suppose why I did it this way is that I didn’t have much material at the time but in hindsight you could do that if you had enough material. It might take a while for the avocadoes to take up the nitrogen in the soil if they are further apart. Most of the nitrogen input you’re going to get from the foliage.
Member That Leucaena is not a nitrogen fixer with nodules – it’s the leaf that you just let rot?
Ross The nitrogen that goes into the leaf is fixed by the nodules so every time I cut it, those nodules get shed so the tree gets stressed so there’s nitrogen going in where the roots of the trees are but also the nitrogen that’s being fixed in the leaf and I throw that material under the avocadoes so you’re getting sources from both.
John Stocking rates in cattle – how does Leucaena compare with kikuyu?
Ross Central Qld is the main area where they grow Leucaena for cattle feed and in comparison, it’s probably double the stocking rate and a third again in production in terms of liveweight gain. They regularly get 1kg per head per day with Leucaena.
Sheryl I’ve got an article at home that says you can get 2kg a day with Chicory.
Member Do horses like it?
Ross No, because it’s got mimosine in it – only ruminants can utilize it. Non ruminants like pigs, chickens, horses should not use it as there’s an alkaloid in it that causes hair dropping. The Thais eat it in salad but you should only eat a little bit.
Member So that’s why men go bald – from eating salad!!
Gretchen Why didn’t you use Pigeon Pea?
Ross They’ll only last about 3-4 years and that’s also the problem with Sesbania. You could use Acacias the same way – Acacia cunninghamii I tried at University experimentally but the problem with Acacia is that it doesn’t break down very rapidly and what happened was you actually used nitrogen from the soil to break the acacia leaf down whereas this gives nitrogen back to the system so that was the problem with the philodinous acacias like black wattle with the big thick leaves. I don’t think we tried any with the compound leaf.
Kelly Our local Landcare Nursery at Maleny do have some that are indigenous species but they might be hit by the local bug.
Sheryl Has anyone else experimented with any other nitrogen fixing plants? We had an article on Lab Lab some years ago.
Peter B Pigeon Peas drop their own seed and up they come. King Parrots also love the seed.
Sheryl How thick do you put your mulch on?