Mastering the art of growing Button Mushrooms
In the outskirts of Ngong town is Murshtec International Ltd that have leveraged in modern mushroom farming. The farm, which sits on an acre piece of land, has several permanent rooms that mushrooms are thriving.
Mushroom farming in Kenya is slowly gaining popularity as more health conscious generation embraces eating this diet. However, many people are taught how to grow mushrooms and not how to consume; hence more awareness is required. Mushroom delicacy is rich in proteins. There are four popular mushroom species currently grown; Button Agaricus bisporus, Oyster Pleurotus spp, Shiitake Lentinula edodes and Reishi Ganoderma lucidun. Out of the four, Oyster mushrooms are the easiest to cultivate; growing in a wide range of substrates and temperatures, and thus referred to as “mushrooms for all seasons”
However, Button mushroom has the highest demand, with Kenya importing up to 80,000 tones to satisfy its tourist industry. This is due to its complicated growing process that makes many farmers shun it. But with the knowhow, this variety pays handsomely. A 250gms sachet retails at Ksh200 in the open market hitting to lows of at least Ksh160 when there is glut.
Murshtec International Ltd started farming mushrooms eight years ago. They are specializing in cultivating Button variety as well as selling Button spawns. “Wheat straw is used when growing mushroom and ingredients include; urea, chicken manure, cotton seed gypsum molasses and mop. The wheat straw is put in a heap for mixing purposes and aeration,” Josephine Wambui, Murshtec Marketing Manager explained.
The process starts by wetting the wheat straw then adding the other ingredients starting with urea and chicken manure. The rest are added on different dates. The process takes about 21 days.
Preparation of substrate for Button mushroom follows a complex stage process involving composting followed by pasteurization. The compost is then moved to the tunnel for pasteurization. This eliminates excess ammonia and sterilizes the compost for a period of between five to seven days. After all the ingredients are added and are evenly mixed, the substrate is then packed in 1.5m high blocks. This removes excess water in the compost and it’s now ready for pasteurization.
After leveling the temperatures in the tunnel, steam is introduced with temperatures of about 60 degrees to sterilize the compost. This takes about 8 hours after with the temperatures are lowered and leveled. “The day before spawning (planting) the temperatures are lowered gradually to prepare the compost for spawning,” Josephine explained.
The substrate is then packed in polythene bags or trays and spawn is introduced. After spawning, the bags are incubated at 20 to 25 degree Celsius, which is the optimal temperature for mycelia growth. “After two weeks, the substrate has colonized and is ready to be cased (putting soil on top of the substrate a small layer of soil is introduced on top of the mycelium and in 10 days’ time, the mushroom starts fruiting,” she said.
“When the mushrooms start fruiting, we open all the windows to allow flow of air and also lower temperature as they require low temperatures at this stage,” she said.
Harvesting sets in after three weeks. The company harvests the produce by hand picking depending on their schedule. They are harvested every day for a period of 1 to 2 months. “It’s advisable to keep the room thoroughly clean as mushroom can be infested by mites which feed on mycelium and the growing mushroom. They are also attacked by snails. Excess ammonia kills the spawns, “Josephine said
Finding Button spawns in Kenya is quite a challenge, Murshtec International imports from South Africa. Besides planting, the company sells the spawns (mushroom seeds) to farmers in the country. A box of spawns retails at ksh23, 000.
The niche market for Murshtec International Ltd is supermarkets but they also sell to groceries and open markets. Wambui states that Button Mushroom farming requires one to be hands-on to reap benefits.
