Biodynamic Blueberries || Elizabeth Burns

Growing blueberries Biodynamically in Victorias Central Highlands

Elizabeth Burns

I am a 5th generation Central Highlands farmer Victoria. My Cornish ancestors (Trewhellas) were berry farmers who bought raspberries with them in the 1850’s. They dug enough gold at Blackwood to buy their farm, famous for their berries and fruit until about 100 years ago, when my grandfather’s generation discovered there was a demand for their land clearing inventions. So for the past 100 years the Trewhella name was more associated with the Jack rather than berries. My dream has always been to return the Trewhella name as prime berry growers. So, it was an honour to be awarded a National ‘Delicious Produce’ gold medal this year.

I studied Agricultural Science at Melbourne University in the 1970’s. However, the application of this training to food production left me concerned about the impact on our soil, environment and human health. A traineeship in Denmark opened my eyes to a gentler, more sustainable form of food production that was reinforced by my travels through Europe and South America.

I first discovered Biodynamics at an Aid project in Ecuador. It was most appealing for its sustainability and did not involve purchasing inputs or seeds. While I looked up Alex Podolinsky on my return to Australia, it was not until the 1990’s that I started experimenting with his teachings.

Despite a brief stint with the National Parks Service and as the Blueberry Industry Development Officer, most of my professional life was as a Community Health Dietitian, educating consumers about their food and developing Community Gardens. I farmed in my spare time.

Raised on home grown (organic by default) food, I became increasingly concerned about the lack of flavour and keeping qualities in commercially produced food.

If fruit and vegetables tasted better and kept better, there would be much less food sent to landfill and a healthier population. However, if everyone decided to eat the recommended intake of fruit and vegetables, we would have to import 90% as our capacity to meet the dietary guidelines from our own production systems would not cope.

This is my journey in producing the best flavoured blueberries. My gold standard has been Moondarra. Having a loyal consumer base that seems addicted to our berries and willing to pay a fair price, no matter what the rest of the industry is doing is more secure than being subjected to the free market price fluctuations/ Experiencing the extremes of environmental conditions over the last 11 years, has given me even more respect for the Australian Demeter Biodynamic method as developed by Alex Podolinsky.

We have tools to deal with most situations. From drought, to flood, humid, hot or cold overcast summers, frosts and snow in late spring and last year potential flood conditions with 1500mm rain.

It should be noted that these are merely observations from growing five of the oldest varieties (from Moondarra) on mature 30 year old roots at Musk in the Central Highlands of Victoria. The main varieties are Brigitte, Blue Rose and Denise from the early Knoxfield breeding program and Northland and Elliot from the USA. They were all planted in the early 1980’s by Shane Johnson and his partner Chris Wealthy who established the Musk Berry Farm. I watched them develop a pristine 16 ac berry farm of a diverse range of berries with smaller plantings of Nashi Pears, Heritage Apples, Medlars, Feijoas and Chestnuts all designed to provide something to harvest over 9 months of the year.

They provided employment to many of the youth of the area every summer for over 10 years. Their parents helped with the sorting, the farm gate sales and managed a Pick Your Own operation. However, a series of tragedies left Shane managing the whole operation on his own. I marvelled at his energy and commitment, Not realising that I would find myself in a similar situation many years later.

20 years ago he sold a pristine operation at its peak to a Melbourne family who struggled with the steep learning curve and health problems and it went backwards as the wild blackberry and broom moved in. We (my late partner, Peter Liddelow who had a Marketing & Tourism background and interest in Eco-Tourism nicely complemented my Agricultural Science degree) purchased the run down Musk Berry farm mid-winter 2005. However, he sadly developed health problems and died in 2012.

While our two children have been a great help with their own individual talents, they are not farmers. Over the years I have wound back to an operation that I can I have been mentoring a couple of new growers who have planted newer varieties at Trentham so in time I will gain more knowledge of their characteristics. Denise requires a hotter climate than we generally have to bring out its full flavour, but then she is my buffer for when we do have hotter summers. But she is the most challenging to harvest and keep.

The blueberry really needs to be treated as a unique plant rather than trying to adapt research from other plants, except for that done by the Viticulture Industry. Each farmer needs to work out what works best for them with their conditions.

My aim has been to identify the factors involved in flavour development. It is flavour that sells & flavour that brings customers back.

Unfortunately, the conventional food production systems research has focused on yield, transportability, appearance and shelf life. Breeding programs have also focused on these factors with flavour often an after-thought. While genetics is the basis of flavour potential, I believe that as much variation in flavour is derived from the growing conditions.

Flavour guides us to what is ready or suitable to eat. Plants rely on a range of methods to spread into different environments and to maximise their genetic diversity to enable Blueberries use colour and flavour to be eaten at optimum time of seed ripening. They need to be eaten, passed through a digestive tract, preferably as far away as possible, for maximum survival.

My varieties of Blueberries grow best in acid, low nutrient; high carbon (organic matter) well drained soils in full, cool sunlight. Research has suggested that their flavour and antioxidant levels are higher at higher altitudes and latitudes.

Blueberries in their natural state rely on a relationship with a soil fungus for actively taking up nutrients from the soil as required, as they do not have feeder roots. These soil fungi require a high carbon diet. Many of my practices are directed at keeping this relationship happy. Unfortunately, conventional practices of fertigation (forcing soluble nutrients in with water) and herbicides destroys this fungus and produces a berry with less flavour, poor keeping qualities and more prone to pest and diseases. They also require more irrigation water. One of my first research areas was looking at the best source of carbon material to feed both the soil fungi, influence the flavour and provide weed control.

In the process of assessing flavour (via pickers and customer feedback) I learnt that flavour perception partially depended on the age and sex of the consumer. However, the ultimate flavour was uniformly selected as the best by all of my tasters. I set up a trial to see whether there was a link between flavour and antioxidant levels. That is, does flavour help us determine what is best for us? I lined up the nutrition department at one of our major universities with the state of art antioxidant testing equipment so students could analyse the 20 samples collected over the season at different stages of ripening. The same samples were submitted to my taste panels. Sadly the samples submitted to the University were lost and I could not match the taste panels’ assessment with the phytochemical composition of the berry. However, I did learn that while most people agree on the absolute peak of flavour, there is a continuum on either side of the acid/sugar balance for preferences in taste. Mature women seem to appreciate the early ripening with more fullness of blueberry flavour and less sugar, while men and children prefer the over sweetness at the end of the ripening process.

After several years of testing different mulch materials, I’ve settled on wood chip from our Blackwood/Eucalypt pruning’s as the most effective weed control, but our old hay (with up to 40 different plant species) gives the best flavoured blueberries. So I’m now alternating them. Last year, I needed to clear out old hay, in preparation for a bumper hay season, so all the blueberries were mulched with this hay that to my surprise still had some green clover leaf evident and my cows still relished. Better still is the hay left out over winter as its partially degraded and the wood chips are best left for a couple of years to start their breakdown process. As blueberry plants cannot translocate (move water and nutrients from branch to branch), the whole root zone needs to be moist and have equal access to nutrients.

If I was setting up a new plantation, I would prefer micro-jet irrigation. But as my plants are nearly 30 years old with very deep and expansive root systems (over a metre depth) and an average 1000 mm rainfall, they do not require irrigation. Instead, I use the previously installed drip system as an adjunct to rain. Or I use it as a cooling system during the extreme heat events, the evening before a predicted hot day.

The size of the berry is related to pollination. Having a diverse range of pollinators maximises pollination and therefore size and yield. They also prefer cross pollination with different varieties, so mixing several varieties that flower at the same time gives a better pollination rate and larger berries. I used to curse Chris and Shane for taking this advice too literally so different varieties are mixed within the rows making harvesting even more challenging. Until last summer I came across a Brigitte surrounded by Northland with even cherry sized blueberries and intense flavour. Our native heath in the bush surrounding the blocks brings in a range of indigenous pollinators in August, prior to the blueberries flowering in September when it is still too wet and cold for the honey bees that become more active later in the flowering season. The eastern spine bill birds also visit the blueberry flowers when it’s too wet for any insect to work the flowers. An entomologist friend has a special interest in indigenous pollinators. So far she has identified over 30 different species and suspects that our potato industry could also play its part. A couple of seasons ago, flowering started too early for the bees, but pollination did not seem affected.

When we lost 90% of our blueberry blueberry flowers during a week of late frosts and snow in October 2006; Alex suggested that we should use the Valerian spray the next spring at the first sign of a frost in the late afternoon during flowering.

This has been an enormously valuable tool as one can feel the warmth and protection of the Prep 507 Valerian spray, which is used sparingly. Very few blueberries have been lost due to frost since. But as the Bramble berries flower later, I had not been giving them a Valerian spray until the year before last, the berries from the bottom half of each plant was lost to a late frost. So they too are included in the Valerian spray program.

The production system that has evolved over the last 10 years commences in Autumn around the Equinox as the blueberries that ripen after this date, do not seem to have as good a flavour nor keeping qualities except for this last season, they surprised me with continued ripening up to late April. I attributed this to sunlight hours rather than temperature. As soon as the harvest is finished, the plants all get a good soaking either from the dam but preferably from the sky. This aids the plant in forming fruit buds for next season. The nets are then removed for the birds to complete the final clean up; inter-rows mowed and any remaining mulch raked out to provide maximum access for the Biological soil Activator Prep500 to make contact with the soil. Ideally, the mulch has broken down by itself and doesn’t need to be removed. Applying the mulch in Spring is a skill in itself to work out just enough to cover the soil but allowing for summer rain and air to penetrate and for most to be reabsorbed into the soil by Autumn.

Once the Prep 500 has been sprayed out, compost making starts while waiting for full dormancy to commence pruning. The window of opportunity for pruning is getting smaller and smaller each year. So this becomes the priority on every dry day. Pruning’s are left in the rows to dry out enough to be mulched in with the spring slashing.

The Fruit Tree prep made from Clay, Cow Manure, Sulphur and Potassium Silicate is applied as soon as pruning is complete. This seals the bark from over wintering pests and diseases and provides some nutrition at bud burst. It has particularly been effective in protecting my plants from Elephant Weevil damage. This is the major pest to Victorian growers.

The spring 500 is applied as the soil warms up after which the compost is spread and covered with mulch. This happens around flowering, so gives me a great opportunity to watch that pollination is occurring and to watch out for impending frosts. I always carry a pair of secateurs for minor pruning and sometimes a final bit of weeding around the base of each plant to allow good air circulation.

The sight of small green blueberries developing always brings great pleasure. The Preparation 501 (ground quartz silica) is sprayed out early one morning in moist conditions and avoiding strong sunlight.

Nets to protect from birds are then rolled out as loosely as possible to ensure that they Then when the Currawongs turn up, I know the blueberries are ready. They only come when the blueberries are at their peak flavour. They sit on the top of the nets and harvest those I cannot reach. They are territorial and discourage the parrots and strangers of all sorts. In fact, as the parrots are seed eaters, I have found that leaving patches of grass go to seed gives them an alternative and preferable feed source. I get the sense it’s the same flock coming back each year and we have developed a kind of understanding of each other.

It is essential to harvest berries at their peak ripening during the cool of the day and keeping berries cool maximises their keeping qualities. Blueberries cannot ripen post harvest. Underripe blueberries literally implode from inside and become mouldy in storage. There is nothing that can be done with an under ripe blueberry and given that they put on a further 25% in weight to full ripening, harvesting under ripe blueberries affects the final yield. Whereas, a perfectly ripe blueberry picked and kept cool, can last 3 months in the cool room, minimising waste.

I’ve done the bulk of the picking over the last two seasons, as it also provides me with feedback on my pruning techniques and environmental factors influencing flavour. Blueberries rely on photosynthesis from full sunlight reaching the leaves, preferably the earliest morning sun possible. The best berries are well hidden in the leaf canopy. If the temperature rises above 30 degrees, the leaf shuts down and the ripening process is hindered by lack of sugar development. However, the tart blueberry holds its flavour better in the freezer, so hot weather is not a real problem.

As with all fruit, nut and vegetable production, there are gluts during the peak season that need to be managed. For me, freezing not only improves the nutritional value of the berry, but evens out my income during the off season. Frozen berries have more available antioxidants. Traditionally, blueberries would be dried by the Native Indians for use over winter. All the research into the health benefits of blueberries has been done on the freeze dried form as it can be powdered and put into capsules for double blind crossover trials. We are just assuming that the same health benefits are in the fresh form.

One of the other observations gained by doing my own picking is the interaction with other plants in flavour development. I have counted over 40 different plant species growing on my land that makes up my hay and the inter row plants, that has led me to observe that blueberries that are genetically identical have a variation in flavour partly due to the neighbouring plants that chose to grow within their root zone. For instance Eucalypts bring in a menthol flavour. Docks indicate drainage problems and blueberries do not thrive in poor drainage and can taste off; clover suggests that the pH may be getting too high and sorrel indicates that the pH is perfect. A self sown currant bush amongst the blueberries brought a sourness that no amount of sun can shift – so it’s coming out this winter.

I have a small herd of Dexter cows (a dual purpose, small Irish cow that is easy on the land, quiet, calves easily and can be milked or provide meat) grazing my paddocks and provides us with good fire protection, weed control, manure and meat and a source of converting waste horticultural produce. My neighbours are part of my Demeter certification and so get the value of living on a certified Demeter biodynamic property, sharing produce and save fossil fuel and costs from slashing every spring. Animals graze neatly up to the fence line. I also get a great buffer zone around my berry production; manure and hay for compost making AND best of all extra sets of eyes at calving time. Dolphins Hill is unique in its mineral composition. The water that flows from its many springs is pristine. Sometimes, I wonder just how much the water contributes to the flavour.

My poultry are producers of high phosphate manure to complement my cow manure in the compost. Some years ago, Alex suggested that I incorporate Blood and Bone into my compost as we both agreed that the blueberries were showing signs of insufficient phosphate. I decided to try my poultry manure first, which I had left out knowing that blueberries do not like excess Nitrogen. The idea that I could raise poultry under my blueberries as a pest and disease control and fertilizer system is also something to explore further.

Diversification of product and markets and the interrelationships between enterprises helps with economic survival in farming. Flavour and word of mouth not only is the best marketing tool but also saves landfill from the alleged 40% of food that is discarded each year. I suspect that a lot of food is purchased and not eaten due to poor flavour or keeping qualities and therefore discarded. If a food system was based on flavour and good keeping qualities, a lot of waste and fossil fuel could be saved. The improved nutrition from an increased consumption of fruit and vegetables could Last summer, I set myself the challenge to harvest every berry at its peak flavour. Effective netting resulted in less than 1% wastage until a hiccup at the end of season with a transport issue, which increased my losses to 10% - still a lot lower than the conventional industry. However, to achieve such efficiency requires superior skilled labour than is available and produces a more expensive product. Having worked out how to produce a well flavoured blueberry that can last 3 months in the fridge with minimal inputs and waste, I will now turn my attention to educating consumers to support such food systems and other growers prepared to put in the labour. Ultimately, I believe that it is the development of the Australian Demeter Biodynamic method by Alex Podolinsky that has the capacity to provide superior quality food, with less inputs, less waste and less water.

To be fully present and in tune with the farm and timing of processes simply does not give time for off farm work. This is our greatest challenge – to enable farmers to be fully present on their land and paid a fair return for their labour.