GROW OYSTER MUSHROOMS. Step-by-step images. See this ‘Before and After’ picture taken over the weekend. Even with the colder winter temperatures, the mushroom fruit is growing very nicely. Fast growth of oyster mushrooms – in KZN winter conditions. Mushrush is quite happy with this method of growing mushrooms. Mushrush South Africa Mushrush Growing Oysters Mushrooms in South Africa. Easy and simple, step by step. GROW OYSTER MUSHROOMS – Here are some basic tips.