Those growing Durban Poison with standard or feminized seeds should expect to pay $10-15 per seed. Growing Durban Poison with standard or feminized seeds is considered to be easy and produces a high yield. The healthiest Durban Poison plants will grow to be tall, especially when grown in soil. Flowering time for Durban Poison is 7-9 weeks. With all of this said, if you’re growing Durban Poison with auto-flowering seeds, you can expect the process to look slightly different. Auto-flowering seeds will flower automatically regardless of the light cycle, and will usually be ready to harvest in 7-9 weeks from seed.