If you used any nutrients, you’d want to start the process of flushing on week 8. This means you stop giving your plants anything other than water. You don’t want any of that stuff in your final harvest. Flood the plant’s soil so that any excess chemicals are cleared before the plant can eat any more of them. This will prevent those chemicals from remaining in the plant when it’s time to harvest. Repeat the flooding process multiple times for up to two weeks, but don’t overdo it. Allow your pot to dry out between flushings.
This week is when the important stuff starts to happen. The fan leaves are sprouting, enhancing the photosynthesis process, and increasing your plant’s ability to create potent flowers. You should be focused on keeping your plant watered (but not too watered!), maintaining a constant temperature, and making sure it has light (if growing indoors). Trust us, this is not the time to be figuring out fertilizers.
How do you maximize autoflower yield?
Week 5-6: Flowering
How fast a specific auto flowering strain takes to reach harvest can depend on the type of strain. However, it generally takes 8-10 weeks for most strains. Some strains require up to 12 weeks.
Harvest up to a pound
What size pots should I use for Autoflowers?
That is the point.
You also need to watch the temperature in your grow room. Cannabis does best at a moderately warm room temperature of 20–25°C. Any excess heat, but also cold spells or chilly nights, can stress your plants, slow their growth, and result in poorer yields.
Then again, if you happen to be a medicinal cannabis user, or for some other reason choose not to get high, a low-THC, high-CBD strain like the excellent Solomatic CBD can be a good choice.
You can find out more about making an optimal potting mix for your autoflowers in our blog **The Best Soil For Growing Autoflowering Cannabis.
TIP 12: FLUSH
You don’t need to harvest your entire plant all at once! Chances are, the top buds may be done earlier than some of the lower buds further away from your lights. These buds may need a little more time to ripen. So instead of taking your clippers and collecting them all, take only the topmost buds and allow the others a few days more to finish.
Note: Depending on where you live, there may be legal limits on how many plants you can grow for personal use, so make sure you know how many plants you can have.
“Flushing” is when you stop feeding nutrients, and only administer pH-adjusted water in the last 1–2 weeks before harvest. This gets rid of the remaining mineral salts that have accumulated. Without any nutrients remaining in the soil, the plant will draw stored nutrients from its foliage; this is why cannabis in late flowering turns yellow. The goal of flushing is to make for purer and better-tasting buds, as you don’t want to smoke whatever chemicals you’ve fed your plants. So flush them out before you harvest.
With autoflowers, you don’t need to worry about light schedules like you would with photoperiod plants. When growing autoflowers, you can just leave your lights on a 18/6 schedule (18h on, 6h off) for the entire grow, and can even grow them under 24 hours of light. Which schedule is “better” is open to debate. Many growers use the 18/6 schedule, as this gives good results while using less energy than a constant 24h cycle.
Also, buying from a reputable breeder or seed bank will give you a sense of what a particular strain will look and smell like, how it will grow, and how much it will yield at harvest.
Pre-flowers can initially be extremely small and hard to identify with the naked eye, but you can use a magnifying glass to get a better look.
How weed clones work
If cannabis is legal in your state, you can buy seeds or clones from a local dispensary, or online through various seed banks.
Most seeds that you will buy are regular seeds as described above, but here are a couple more types.
If buying from a reputable breeder or seed bank, growing from seed is the best way to ensure your plants will have solid genetics and start clean, meaning they won’t come with diseases or pests.