High-performance Mānuka Plantations
The mānuka honey industry depends on wild harvesting of honey – this is where hives are set up in areas that naturally have a large number of mānuka trees. Methylglyoxal (MGO) is formed from the conversion of dihydroxyacetone (DHA), which occurs in the nectar of mānuka flowers, during the production of honey in the hive. The higher the levels of DHA in the mānuka nectar, the higher the potential medical grade and the more valuable the honey will be.
A Primary Growth Partnership initiative, the High-performance Mānuka Plantations programme, has brought together key stakeholders, including Comvita, the Hawke’s Bay Regional Council and Massey University, to look at how the industry can move from wild harvest to the science-based farming of mānuka plantations.
Roger Bourne
The Hawke’s Bay Regional Council has teamed up with Comvita, Massey University and others as part of a PGP programme called High-performance Mānuka Plantations.
Around 2011, about 5 hectares of mānuka was planted to assess the potential for erosion control while creating a source of high-value plants, capable of enabling bees to produce high-grade medical honey.
The trial was soon expanded to cover 140 hectares. Regional Council Chairman Fenton Wilson explains.
Fenton Wilson
The mānuka trial that we’re doing here at Lake Tūtira is ground-breaking for us on the basis that it’s taking a nutrient issue we have with the hills around here, which are affecting the lake, and turning it into a productive solution. So the council is incredibly enthusiastic about the potential of this to help us manage nutrient issues going forward.
Sediment nutrient issue that’s affected the lake, it’s now prone to algal bloom. Nutrient levels are too high, and you know, there’s a range of issues around that, but the main one is nutrient ingress, I suppose. So it’s a New Zealand problem, and if we can find ways to fix it and make money for a farmer, it’s got to be good.
It’s a 40-year project to fix Lake Tūtira. We’re on year 20, I think at the moment. We needed to find a way to get money out of the hills. So we approached Blue, actually, the guy that leases the place, to see if we could do it, and he’s been very accommodating.
Campbell Leckie
The mānuka trial here at Tūtira, really that was about saying, in our hill country, we’ve got large areas of erodible land, and some of that land is not getting a good return in terms of stocking return, and a tree crop, if it’s the right tree crop, could make a difference. So the trial here was to say, “Can we get this high-MGO mānuka, have it establish in our rougher hill country, in a way which actually adds value to the farming enterprise?”
Really strong partners in this, particularly in terms of the mānuka trial, is Comvita – really important partners. So Massey University – so we’re tied into the Primary Growth Partnership, which is part of this driving this high-MGO mānuka across New Zealand. And in that, there’s a bunch of partners – Landcorp is in there, Te Tumu Paeroa, some private investors.
What we’re talking about potentially here is probably quite ironic to a bunch of farmers. In fact, you talk to them about it, they used to cut a lot of mānuka down. But the reality is that this high-MGO mānuka, there’s significant markets, particularly in medical and cosmetic-grade products, and those actually can drive quite a bit of value at the farm gate.
It is pretty early days in terms of the thinking for the future, particularly how the relationship works between the farmer and the beekeeper, and investors as well. It’s pretty early days. But it would be fair to say that a solution where the farmer is putting up the land and getting obviously part of the honey crop, and clearly from the beekeeper’s point of view, they want a vibrant beekeeping industry. And so there’s a whole bunch of things that need to be managed around that. There’s disease, there’s hive placement, there’s having strong hives throughout the course of the year.
150, 250 bucks per hectare per annum would not be unrealistic, and when you compare that as a net return to some of the steep erodible country and what it does actually deliver in a farming sense, that’s probably reasonably attractive.
Other regional councils are definitely involved in looking at mānuka and so how we partner up, in terms of our region – so we’re looking now, and we’re talking about what those partnerships might be and what the funding models might be, because in terms of scale, there’s about 150,000 hectares, roughly, of country that could be in a better land use and drive better economic and environmental performance. And that’s a big chunk of land, and so it actually requires a lot of partners to invest to drive the outcome.
Georgie Hamilton
In the nectar, we’re looking for a component called dihydroxyacetone, or it’s shortened to DHA. And so that is the precursor to methylglyoxal, which is the antibacterial component in the honey. And we also test the nectar sugar, so we can use that to look at how much honey we can produce from these cultivars.
We know that genetics plays a role in their quality. So Comvita has set up a breeding programme, and there’s four main cultivars planted here, but there’s actually about 16 varieties planted here in total that have been bred by that breeding programme. So, they’ve been selected from stands and cultivars of mānuka that are known to produce high levels of methylglyoxal in the honey.
Once they’re planted, we monitor their establishment using circular plots, and we look at their survival and their growth. And when they get to 2–3 years of age, when they have significant flowering, we test the nectar, and we also take honey samples to look at the apiary data that we get the beekeepers to help us with.
A lot of this is planted in broadacre – so that is usually planted at about 1,100 stems per hectare – but at Massey, we are looking at different spacings and how effective those different densities are.
There’s a lot of pest issues during the establishment phase, so pest control is vital for establishment of them. The other main pest that we also look into is scale insect, which creates sooty mould on the trees. So, we have a PhD student who is looking into the effects of scale insects and sooty mould on the growth and the quality of the honey.
For the first few years, they get nibbled by stock, but in some situations, and especially here at Tūtira, they have put sheep in once they’ve reached about 3 years. And the sheep generally don’t browse them once they’re above their eyesight. So they seem to be fine with light grazing from sheep.
We have multiple field sites all across New Zealand that we monitor. They all have these cultivars planted at them. At those sites, we assess the soil, the climate data.
We are quite close to being able to recommend some cultivars for specific sites. We already have cultivars that we know do well in specific areas, for example, drought areas or frost areas.
We’re only still in the establishment phase, really. So we have quite a lot of data on establishment and survival. We’re just starting to get really into the quality. So we have taken nectar samples from most of our sites now, and most sites we’ve done 2–3 years of nectar sampling at. So here at Tūtira, we sampled the cultivars that are planted in the plantation – their nectar – so that’s producing significantly higher levels of DHA than the local mānuka here. So that’s quite promising.
Acknowledgements The Science Learning Hub thanks Showdown Productions for the use of this Rural Delivery video clip.
