Quick answer: An autoflower may finish in roughly 8–12 weeks from seed, an indoor photoperiod grow often needs about 12–20+ weeks, and an outdoor seasonal crop can take 4–7 months. Genetics, light, plant size, environment and grower decisions change the total.
Whether you ask “how long does weed take to grow?”, “how long does weed take to harvest?”, “how long does cannabis take to harvest?” or “how many months does weed take to grow?”, the most useful answer is a timeline rather than one number. Separate germination, seedling, vegetative growth, flowering and post-harvest time when planning your grow.
| Grow type | Typical seed-to-harvest range | Why it varies |
|---|---|---|
| Autoflower | 8–12 weeks | Genetics and stress |