Topical Tropical Organic

Tim Marshall recently returned to the North, visiting organic and biodynamic growers in north Queensland and the Northern Territory.

Not surprisingly, most successful commercial organic farmers in the north grow that magnificent tropical fruit, the mango, or bananas, or row crop vegetables and melons. The range of vegetables grown is quite broad and includes the familiar carrot, beans, squash, cucumber, tomatoes etc. Melons are very popular, mainly rockmelon and watermelon with some new asian melons also appearing. Some other tropical fruits are also grown and interest is developing in an organic sugar industry. Other organic crops, on a small scale, are tea, coffee, tea-tree and neem. There is a small stirring of interest in cocoa too, but I could locate no farms producing commercial quantities of organic cocoa.

Peter and Beryl Watson, Tully

Drive south from Tully for 20 minutes and you will come to the turn-off to Murray Falls. If you have time to enjoy the tourist experience in the tropical north, the falls are well worth a look. If you want a sweet, fresh organic banana, stop by Peter’s Organic Farm on the way. Almost the first farm below the falls, and protected by the wilderness from which the Murray River emerges above the fall, Peter and Beryl’s Watson’s organic farm is one of my favourite stops on any visit to North Queensland.

Peter grows bananas and sweet potatoes, with the assistance of son-in-law Gordon. This year was very wet, and many of the bananas on lower ground spent too long under water, so this season’s production is mainly limited to the higher paddock.

Some locals will tell you that the pests are overwhelming in these northern climates, but pesticide inputs are quite low on Peters Organic Farm. Some natural pyrethrum is used on bunches and a backpack sprayer is used to apply diatomaceous earth to bunches for thrip control. Bordeaux was been used for leaf fungal disease, but Peter now prefers summer spraying oil, to provide a spell from copper. Banana borer is a minor problem, the old stools are thoroughly chopped up and new ground selected for each successive planting.

Peter and Beryl have up to ten WOOFERS at one time staying on the farm, three at the time I visited, with another expected on the next day. Willing Workers On Organic Farms, otherwise known as WWOOF, was originally started to provide experience on the land for intending or would-be farmers. In has now broadened to a work-for-keep system, where the host farm provides meals and accommodation in exchange for labour. It is used by many backpackers to extend the length of their stay, when travelling on a small budget. WWOOF can provide a good option for many farms with labour–intensive activities. The down-side is that much of the labour is unskilled, and WOOFERS can need a lot of management. WOOFING tends to suit farms where the host is very social, and where there are basic labour intensive jobs such as weeding, planting and simple harvesting operations.

While I was at Peters Organic Farm, I spoke to WOOFERS Liane Amels, from Lutherstadt Wittenberg, in Germany, and Sabita Bharos, from Wageningen, The Netherlands.

Liane: “I have not started my university studies yet, but I will do something when I get back home. I have been in Australia three months, and I have been to some other WWOOF farms. I went to a camp farm near Gympie, where I helped out with children, and magnetic island, where they had two acres and a small orchard. At Milla Milla I stayed on a beef cattle place, which was isolated, and at Watson’s dairy. I liked working with the cows there, and I learned about biodynamics. They were very good and treated me like part of the family. At another place where I stayed I planted trees and had to help out in a guesthouse. I did not like that, so I moved on to an entomological museum, where I did building and gardening.”

“I like it here at Peter Watson’s too. I have been weeding bananas, planting bananas, helping in the household and feeding calves. It is really good and I think I have learned about living more sustainably. Here they are very self-sufficient. They make a lot of their food, and grow a lot, and I think I would like to try to live more like that.”

“I have not decidied what I want to study yet, but after being here I think that maybe I would like to study organic farming.”

Sabita: “I am an IT consultant, but I have taken one year off for travelling. In Canada I stayed on an organic orchard, with apricots, peaches and cherries. I also stayed at a goat and sheep cheese dairy, which was very small scale and sustainable. I like the sustainable way Peter and Beryl live. They make their own bread and they have a vegetable garden and chickens.”

“Some of the WOOF farms aren’t organic, and some don’t even really have much of a garden. It is great to find a really good organic farm and to learn about where our food comes from, or see a way of living more sustainably.”

Far North fruit and vegetables

Neil and Norma Robson are organic vegetable and mango growers at Mareeba, (see Acres Vol 2 No.2 and Vol 2 No.2). They are no longer certified, for their 3.2 hectare of vegetable production, or 6.7 hectare mango plantation and small mixed tropical fruit orchard. Frustrated with the certification systems and the problem of sending produce south, they are now happy to supply the popular Rusty's Bazaar (a well attended local market) at Cairns and a local organic store. Neil has maintained his organic practices, but is clearly not happy being told “how to run my farm”. He told me “people come to the farm to collect produce, and at the markets they ask questions about how it is produced. I don’t believe I need the interference of the certification organisation, and I am think the customers are happy to get to know me and extend their trust to us.”

Maurice Franklin, Mission Beach

The use of leguminous groundcovers is critical for reducing the work load in the tropical fruit orchard. Pinto peanut is proving to be a very useful groundcover for banana grower Maurice Franklin at Mission Beach. It is a legume, which produces nitrogen, it has small yellow flowers that attract beneficial insects, and it performs the critical function of greatly reducing weed growth. Mauri has invested some effort in studying the pinto peanut, including selection of low growing varieties and establishment methods. The most desirable forms are aggressive competitors of grasses, yet grow close to the ground and do not climb up the banana plant. They should also have high shade tolerance, be able to withstand mowing, and produce significant nitrogen.

Maurice is convinced that “pinto can dominate grass”, but he warns “it is sensitive to mowing height. I have experimented with different strains of peanut and mowing heights, with the aim of making conditions more suitable for the desirable plants and less favourable for the unwanted grasses and weeds.”

The area immediately around the banana plant is flamed with a tractor mounted flame weeder.

maurice franklin

Maurice is trialing molasses for nematode control, with apparent success. Despite the perception that pests in the tropics will overwhelm any organic crops, very little botanical (ie ‘organically acceptable’) pesticides are needed. The orchard is alive with many types of insects and small animals, including various ant species, numerous beneficial wasps, wolf spiders, ‘crab’ spiders and the largest assassin bug I have ever seen. Lizards, geckos and green frogs abound, and birds. We found evidence of some rust thrip and flower thrip, but Maurice is happy with the over all balance. He says “you need some of the pest insects to feed the good ones, otherwise the good ones would move out”.

Leaf spot disease remains a problem for organic banana growers. It removes leaf cover, which limits photosynthesis, but it also reduces the shade cover, which is needed to restrict grass growth under the bananas.

Maurice is a delegate to the Banana Sectional Committee of Queensland Fruit and Vegetable Growers, a position which he takes seriously. He says “I try to grow big, good crops well, to encourage others. I am involved with political organisations to influence the direction of agriculture, in favour of a sustainable, farmer friendly system.

Rob and Sally Watson

Rob and Sally Watson, graze dairy cattle on 200 hectares of land, on the south-eastern edge of the Atherton Tablelands. They use biodynamic farming methods, practice a rotational grazing system, and are establishing pinto peanut into all paddocks. The Holstein-Friesian herd is being changed to Aussie Red and Brown Swiss cattle.

One of the main problems, in this tropical climate, is ticks, which are treated with sulphur added to a grain ration, and with homoeopathic tick and flea remedy, tick ‘peppers’ and neem. Buffalo fly is also problematic. While I was visiting, Rob and his brother Danny were making adjustments to a fly trap, designed by CSIRO, but in need of improvement. Cattle have to leave the dairy via the walk-through trap. The idea is that it is very dark in the trap, except for a skylight. The flies are disturbed by a brushes, and fly towards the light. The trap works reasonably well, after cattle become adjusted to entering the dark opening, but the flies, which are supposed to be killed by heat exhaustion in the trap manage to fly out and recirculate back into the herd. Rob is experimenting with suction, to pull the flies through an exhaust fan, into a collection ‘sock’.

Antibiotics are not necessary, and mastitis is managed with the use of nurse cows, or by culling.

daniel watson

Rob and Danny are very happy with the performance of pinto peanut. They say that a few ‘conventional’ growers are becoming interested, and some have started to plant pinto. They cannot understand why more don’t see the benefits of peanut over nitrogen-fed grass. Soil development under the biodynamic pastures is remarkable. Tropical soils rarely display the structure, depth and colour that these soils have, even though the Atherton soils are of volcanic origin dark The example of these soils speak powerfully of the potential for biodynamic management in the north, and in years to come many of the local dairy families will be challenged by field days on the Watson property.

Distance from biodynamic grain producers has been a major expense, as the entire grain ration has to by certified Demeter, and transport expenses are significant.

Distance from markets also limits the potential for sale of biodynamic milk, so they will make yoghurt and cheese. Rob has completed a cheese-making course and developed some experience in a local factory, and they will be selling Demeter certified products in a few years.

lloyd pierce & chris landen-lane
Magnificent mangoes

Lloyd Pierce was the first certified organic farmer in the Northern Territory. His NASAA certified Humpty Doo organic mangoes are a popular item in the Sydney market and some are exported to Europe.

Supply of organic mangoes to the Australian market is still a problem, as the hot dipping technique for fruit fly control is not accepted in all states. This is because state departments of agriculture have non-uniform standards, and despite the arrival of hot dipped mangoes into Australia from Mexico.

The hot dipping technique involves submerging the mangoes into a bath of hot water, and maintaining the temperature at a precise level (around 46 degrees) for ten minutes. The fruit is then cooled and packed. The technique was experimented with and developed by Lloyd for control of fruit fly, but has proven very useful as a control for anthracnose also.


Like most organic farmers, Lloyd has always had a percentage of fruit that was unsuitable for the fresh fruit market. Lloyd believes this to be around 10-15 percent for his mangoes, mainly due to rub marks. Even with magnificent organic mangoes, there is a limit to home consumption, so it became necessary to develop a market for the rejects. As juice markets were not large, accessible or organic, Lloyd decided to explore drying, but that proved difficult in the very humid environment of Darwin. Lloyd is now making a frozen mango “Icee bar’ – containing only pulped frozen organic mango.

As in my previous visits to Lloyd Pierce, the environment of the orchard was alive with insect sounds. Bees buzzed, hunting wasps hovered and birds, lizards and frogs were a constant reminder of the teeming life of the tropics.

Weeds under the trees are ignored or simply slashed. They provide large inputs of organic matter during the wet and many are leguminous or deep-rooted. The mango tree is largely self mulching when mature, with a continuous leaf drop. The tree roots are close to the surface feeding on this decaying organic layer, but we suspect that when nutrients escape the surface layers into the soil they are quickly fixed in the ironstone "buckshot" soils or leached from the highly permeable tropical soil. Soil disturbance needs to be minimised to prevent erosion in torrential monsoonal rains and to avoid rapid burn-up of organic matter in high temperature conditions.

Under tree sprinklers help to create conditions for best utilising this valuable organic layer under the canopy. Where the tree are still young the ground heat in the orchard is oppressive, but as the trees spread and cover the ground it becomes cool and a welcome relief from the hot sun.

Search this site with Google