Growing cannabis isn’t as simple as germinating seeds, adding fertiliser and watering regularly. You have to do a bit of research and learn as much as you can about the growing stages of each variety. Autoflowers are a type of feminised cannabis with Ruderalis genetics. Put simply; this means that you don’t have to alter the lighting schedule to put them into the flowering stage – they do that by themselves. To enjoy a successful autoflower harvest, you will need to understand the science behind the autoflower life cycle.
Explained week by week: the life cycle of autoflower varieties
To make it easy for you, we have created this introductory guide.
1. Autoflower germination
Let’s start at the very beginning with germination. There are various ways you can germinate cannabis seeds, and autoflower seeds are no different from any other strain in that respect. One popular method involves soaking the seeds in a glass of water for 48 hours and then placing on a couple of sheets of kitchen towel before enclosing in a clear Ziploc bag. You may wish to roughen the surface of the seeds with an emery board, but this is not strictly necessary. Once you notice the creamy taproot emerging, it is time to plant the seeds carefully.
You could also use starter cubes, or simply plant your autoflowering weed seeds directly into the soil. This might actually be the best method for germinating autoflowers as they do not like to be repotted.
2. Transferring the seedlings
The next action is to transfer the tiny and delicate seedlings to the growing medium of your choice. Wait until there are two pairs of leaves emerging from the seed as well as the taproot. Take your time; there is no rush; this is the most sensitive stage and one which can be avoided if you plant directly into the containers you plan to use (they should be between 1.5 and 3 gallons in size). Make sure the lights are not too close to the seedlings – at least 17 inches away – and of the correct intensity. If you touch the seedlings at all, handle them by the leaves and not the incredibly fragile stem.
3. The first three weeks
During the first week, the seedlings don’t need any additional nutrients, Just ensure the soil is kept nice and moist, possible by using a water mister. Be very careful when watering as a sudden gush of water could wash the seedlings away. It is also important not to overwater as the developing root systems of the seedlings are also incredibly delicate.
In Week Two, you will hopefully observe the seedlings growing more vigorous with each passing day. Now is the time to introduce some mild nutrients unless you are using compost with pre-added nutrients. Place the lights a little closer to the plants if you notice that they are looking a bit lanky.
In the third week, you should notice more sets of leaves emerging. Remember, autoflowers generally have a seed to harvest time of eight to ten weeks, so you are nearly a third of the way there! Autos are usually feminized cannabis seeds but if yours aren’t now is the time to watch out for signs of male and female plants. (The males can be identified with their tiny sacs of pollen, while female plants have pistils). You can now offer nutrients at the advised dosage, but take care not to overdose your plants, and look out for signs of root burn.
4. The next two weeks – 4 to 6
The next two weeks see your plants reach the vegetative phase and are crucial for determining how big they will grow. Now is the time to introduce training methods such as Low-Stress Training (LST) or Screen of Green (ScroG) to increase yields. You will need to continue to offer nutrients at full strength, although it’s essential to read and comply with the manufacturers’ instructions carefully. And remember, even though your plants may be showing pistils they are not at the flowering stage yet. So if your fertiliser has two parts – Grow and Flower, for example, you should continue to use the Grow element at this point.
When to use nutrients, you shouldn’t forget to check that the pH is the correct level.
By the start of week five, you will notice buds beginning to emerge whilst lush leaves continue to grow and develop. Nitrogen is the most important chemical element for your babies at this stage when their growth rate will dramatically increase. You will want them to grow horizontally as well as vertically, so it is vital that they have the right fuel to do so. You might be tempted to add flowering nutrients at this point but try and hold back as doing so prematurely will significantly impact the eventual yield if the plants aren’t allowed to grow to their maximum capacity.
Week 6 arrives, and more and more buds start to emerge. Allow the buds greater access to light by defoliation – the removal of wing leaves – or by gently tucking the wing leaves back, which is a less invasive method as the plants need their leaves for nutrients. Continue with vegetative phase nutrients.
5. Weeks 7 to 9
By this point, vertical growth has ceased, and you will have made the switch to flowering nutrients. The buds will start to grow expansively and become hard and dense. Pistils will begin to change colour from white to amber, orange, to red. You will also notice that the plants have a much more pungent smell; hints of the harvest that lie in store. Toward the end of this stage, the fan leaves will start to turn yellow around the edges. This is an indication that the weed plants are approaching the end of their life cycle.
6. The final week
During the last week, which may be anything from week 8 to week 12 for most varieties of autos – all the leaves will turn yellow, and the pistils may also change colour. These are all signs that it is time to harvest. You can cut the leaves before the buds, a method known as wet trimming, or cut the whole lot at once which is known as dry trimming. It is a matter of personal preference, but the wet trimming method is the preferred choice of most cultivators as it is surprisingly difficult to separate the leaves from the stem once they have dried. Use gloves and sterilised scissors when harvesting cannabis to prevent infection and to avoid your hands becoming coated in sticky resin.
All you need to do now is to dry your harvested bud and take the time to cure it for at least six weeks. And then relax and enjoy your top-quality autoflower bud!