In a PGP, government contributes half of costs when milestones are met - $700,415 for MRPL up until December last year.
The aim of the seven-and-a-half year project is to increase New Zealand's annual earnings from honey from $85 million to $1.2 billion by 2026. Research is being undertaken on 800ha at sites in the North and South Islands, using manuka cultivars developed by health and wellbeing products company Comvita.
Big international interests from the United States, Japan and Australia are looking to get a slice of the lucrative honey industry. As an MF shareholder Mr Walker would like to get his money back - but he'd also like the emerging industry to benefit ordinary New Zealanders. He said the partnership would not be selling cultivars or knowledge to people operating overseas.
MF intends to recoup costs by selling manuka cultivars and giving advice to landowners. It has plants ready for sale this winter. Next winter only pre-ordered plants, grown by contracted nurseries, will be sold.
MF has many shareholders. Comvita has 32 per cent, Tweeddale Apiaries 25 per cent and Mr Walker's Nukuhau Carbon Ltd 14.5 per cent. Te Tumu Paeroa (the Maori Trustee), Landcorp and Hawke's Bay Regional Council all have smaller shares.
Mr Walker is a player in his own right, as well as an MF shareholder. He has manuka interests across three pieces of land in Taranaki and South Taranaki and will have 85,000 more manuka plants in the ground this winter.
His easternmost piece of land is a 40ha manuka trial on a steep slope in Rangitatau West Rd. It was planted in 2011 and 2012 with five manuka cultivars, as 30cm seedlings.
They went in the ground at 3m x 3m spacings - 1100 to a hectare - because closer spaced manuka would only flower at the top. The land has a weather station, to work out the effect of climate. Massey technicians visit regularly - especially during flowering time.
Various spray techniques can be used, to get rid of weeds and prevent the young plants being smothered by dense grass.
They don't flower much for the first three years and improve after that. The ideal is to get a longer flowering period by mixing cultivars from various parts of New Zealand. They tend to continue flowering at the same times, even when moved to a different latitude. Some also flower longer than others.
It could be possible to get flowering from September to February - though Taranaki's famously wet and windy springtimes could be a problem for the earlier cultivars.
Some of the cultivars have nectar with twice as much DHA - the ingredient that becomes methyglyoxyl and makes manuka honey medically valuable.
Pest control for the trials is important.
"The cultivars seem to be attractive to goats and other animals more than just native manuka. You do have to operate a system of culling," Mr Walker said.
He's also got beehives on the land, run by Yobees Honey. It's a joint venture between himself, 22-year-old Johann Ander and others.
MRPL has other trial plots in the Waitotara, Ahuahu and Ruatiti valleys, he said.
Planting manuka cultivars from other regions can muddy the gene pools of local manuka. Mr Walker wants to meet Conservation Department staff to talk about preventing this.
He's also suggesting it gives beekeepers concessions to have hives on conservation land - with the proceeds used for conservation.
Manuka scrub usually nurses emerging native bush. It can be kept as purely manuka by the use of sprays - though Mr Walker said that would not be organic - or by a removal and replanting regime.
The manuka plantation idea has taken off. MRPL's stall at the Central Districts Field Days on March 17-19 was busy. Mr Walker manned it for two days, and had no time for lunch.
Government's latest Afforestation Grant Scheme offers $1300 a hectare for planting forestry and manuka plantations count as forestry. Of the 3000ha taken up by landowners so far, 1700ha were for manuka. The cost of a hectare of typical manuka plantation is about $2500.
Mr Walker said medical grade honey with an ultra manuka factor (UMF) of 20 could fetch $800 a kg. A UMF of 15 could get $644/kg - high prices.
He doesn't believe the Asian appetite for the honey will falter, but said there could be competition from Australia, which has manuka and similar plant species.
His message to landowners is to be cautious about dealings with beekeepers and make sure they get a fair price for hosting hives. The industry is changing fast and it would be wise not to make long-term agreements.
The high price of manuka honey has unleashed some "cowboy" beekeepers.