Bananas and Dairying

A project is underway on a Northland dairy farm to evaluate the banana plant’s effectiveness in mopping up dairy nutrients, as well as providing a nutritious supplementary summer feed for dairy cows in this region where summer droughts are predicted to become increasingly frequent and severe. 

New Zealanders love bananas, chomping their way through 18kg of imported bananas per capita each year – but who knew our dairy cows also have a taste for bananas? 

In the relatively frost-free Northland region, home gardeners and lifestyle block owners have grown and harvested their own bananas for some decades. For the most part they have favoured the Misi Luki variety, which is disease resistant, grows up to four metres tall and produces tight bunches of lady finger bananas.

Now AgResearch has teamed with dairy farmer Graeme Edwards to evaluate bananas as a crop to provide supplementary feed for dairy cows (particularly in times of summer drought conditions) and to help mop up dairy farm nutrients. Prompted by his son Paul, a senior scientist at DairyNZ specialising in farm systems, Graeme planted a mini plantation of Misi Luki two years ago on the 250-cow 125ha family farm at Pakotai, on the way from Whangarei to Kaikohe.  

He sourced some 60 to 70 plants locally, planting them between two drains close to the farm’s green water storage, allowing for a trickle system to be set up to get the effluent liquid to the plants. “The site’s a bit too windy to be ideal with some leaf damage evident, but the plants are really healthy and thriving,” says Graeme. “They grow rapidly, bear some fruit and have lots of ‘pups’, or suckers, that grow off the base and can be used either as fodder for the cows or to propagate new plants.” 

He adds just like cows on farms in countries where bananas are grown, first indications show that his cows love bananas too, particularly the leaves.

AgResearch began its evaluation of Graeme’s plantings in May last year (ed: May 2020) with the aim of delivering proof of concept that growing bananas on Northland dairy farms would increase the economic and environmental sustainability of the dairying sector in the region.

The study is backed by the Our Land and Water National Science Challenge through their Rural Professionals Fund to partner individuals and businesses with scientists to test ideas that could lead to significant improvements in farming systems. NZIPIM, and MPI are involved, with a requirement that projects extend what is learned to the wider rural profession and farming community.

AgResearch researcher Grant Rennie is heading up the evaluation project. “Banana plants can grow quickly in the peak of summer. They are relatively deep-rooted and drought tolerant. Much of their water is stored vertically in the stems. This could be an advantage in Northland where summer droughts are predicted to become increasingly frequent and severe,” he says.

As well as investigating whether banana fruit, leaves and stems are nutritionally appropriate for dairy cows, the project is determining whether banana plants can effectively take up the nutrients in dairy farm effluent and therefore have the potential to be incorporated into a farm’s effluent management system.   

Grant says dairy farmers are always looking to do what’s best for their animals, and to step more lightly on the land. For the most part, they are enthusiastic and innovative in seeking solutions. “With appropriate cultivars, management and location, bananas are capable of being persistent and productive with the result that for dairy farms in the milder Northland climate, the banana plant could become a key component of the farm effluent system, as well as providing plant material as a supplementary feed for livestock.” 

Graeme Edwards says during the summer drought of 2019-2020 the bananas were the only green plants on his farm, and, pending the study’s findings, he would be eager to establish a perennial banana plantation as an alternative to his traditional supplementary annual turnip summer crop.  

As to the taste of the fruit his banana plants are producing, in understated style Graeme says it is OK, but that he personally prefers his bananas blended into ice cream or a smoothie. 

The findings of the AgResearch evaluation will assist dairy farmers in Northland to decide whether it is worth their while to go bananas, both for the benefit and enjoyment of their cows, themselves and the farm. Once the results are in, the team will decide if this novel crop looks promising before they will look at further work like grazing strategies and nutrient management. Separately, there are growers in Northland working towards establishing plantations of banana for human consumption.

Showdown Productions Ltd.   Rural Delivery Series 16 2021