Te Mata Mushrooms was started in Havelock North in 1967 by Stuart Speeden and Phil Hawley. Their sons Martin and Michael Speeden and Chris Hawley ran the business for more than three decades. In 2012, the business was bought by Michael Whittaker, who has retained Martin Speeden as General Manager.
In 1967 when they started growing there were over 50 other mushroom farms in NZ. Today there are only 6 commercial growers left. The farm started at 7 acres and is now around 52 acres.
Te Mata grows mushrooms in traditional Douglas Fir trays with a special compost mix. They’re the second biggest mushroom grower in New Zealand, growing over 20 tonnes of mushrooms every week. That’s over 1,000 tonnes a year.
Martin Speeden is the head mushroom grower, assisted by over 15 permanent and around 90 part time staff. Martin says some of the staff have worked at the company for over 20 years.
Te Mata supplies mushrooms throughout the North Island. Its biggest customer is Foodstuffs. Local restaurant owners and locals buy their mushrooms direct from the farm or at the Hastings Growers Market and the Sunday Farmers’ Market,
They have tried several varieties of mushroom but now specialise in just the white button and Portobello (brown) varieties.
The company’s location is ideal in terms of proximity to Auckland and Wellington, and in terms of climate, with Hawke’s Bay’s low humidity providing ideal mushroom-growing conditions.
Temperature and humidity as well as quality of compost are vital components for mushrooms, which are grown from imported spawn in 19 growing sheds depending on their stages.
It takes 12½ weeks to grow a mushroom from scratch, with new crops put down each week.
Producing the compost is one of their biggest expenses, with straw costing about $500,000 a year. Chicken manure, water and gypsum are added to the straw to make the compost. Compost is constantly changed to ensure the mushrooms are disease free.
The 13 week growing process is a cycle that starts with compost. This takes two weeks. Each summer the company buys around 5000 large 350kg bales of wheat and barley straw. Each week around 60 or 70 bales are set out. Each bale is watered and mixed with chicken manure and gypsum. A compost turner is then put to work running up and down the rows. The compost is then put into bunkers to “compost”.
The compost is pasteurised and conditioned to convert carbohydrates and ammonia into protein. The conditioned and pastuerised compost is then mixed with mushroom spawn at the rate of 800gms per tray load and put into growing trays into the spawn room.
After two weeks the spawn have colonized the trays. Trays are then cased (to ensure a good spread of the mushroom mycelium). Casing is a blend of peat and limestone to ensure a ph of 7.5. The trays are then taken to the growing room for approximately 6 weeks. The first pick from casing is around 16 days.
The first flush of mushrooms appears around 16 days later and then double every 24 hours. Three flushes are picked off that crop, around a week apart. The mushrooms are picked by hand, weighed and then chilled for dispatch.
After harvest the trays are sterilized and the used compost is taken away for garden mulch and compost.
Heating in the growing sheds is controlled by air conditioners. Martin says that when they started they used kerosene heaters.
Mushroom spawn used to come from the company’s own spawn laboratory which was built in 1982. Martin originally brought mother cultures from the UK but today they import spawn from Australia in shipping containers.
A weekly schedule looks like this :
Monday : Empty, mix and refill compost bunkers. The spawn run trays are brought out of the spawn rooms and “cased” where a mixture of Southland peat and limestone are put on the top of the trays and they are transferred to the growing rooms. pH is 7.5 to 8.0.
Tuesday : The two pasteurising tunnels are emptied and the compost is filled into the 960 growing trays with spawn and a slow release supplement. As they are filled, fertiliser is also added. The trays are then placed into the spawn rooms for approximately two weeks.
The compost is taken out of the bunkers on the compost yard and turned and re-mixed with the compost turner. Water is added if needed and the compost is filled into the pasteurization tunnels ready to be pasteurized for next the next Tuesday.
Wednesday : Bales are set out on the compost yard for turning on Wednesday.
Thursday : Turn the bales and fill the bunkers
Friday : The same as Monday.
Used compost is sold to gardeners, homeowners and vineyards around Hawke’s Bay. The farm uses all the surplus compost to fertilise the other crops it grows in the district.
“We get orders from 4.30am, picking starts at 6.30am and the first mushrooms go to market at around 9am,” says Michael.
The majority of The Te Mata Mushroom Company’s mushrooms are sold in the central and upper North Island regions due to the mushrooms’ relatively short shelf life. The main varieties they sell are white buttons, white cups, white flats and portabellos. They grow over 20 tonnes of mushrooms each week – one million mushrooms!
Produce which is not the right size or shape is used to make products such as stock and soup.
“The key to the continual success of our mushroom production is having staff that understands and can adjust the compost mix depending on a number of variables such as the consistency of the straw, which changes with the seasons. It is important to have a good picking and packing team who take pride in the picking and presentation of the mushrooms,” says Michael.
Mushrooms double in size each day so need to be picked all the time.
“We can’t skip a day of work just because it’s a public holiday, the mushrooms must be picked and packed every day except Christmas Day.
Te Mata hit the headlines recently when it introduced vitamin D mushrooms to the market – using ultra-violet technology which simulates the fungi to produce the vitamin naturally. “We recognized that mushrooms are the only non animal product that produces vitamin D naturally, but they need to be exposed to sunlight to do this. We brought Xenon UV technology in from America which enhances the vitamin D within our mushrooms. No other mushroom producers in New Zealand have this technology at this stage.”