This article continues our series on growing under 12/12 lighting from seed.

For this experiment, we sprouted our seeds using the paper towel method, and then planted them in a red solo cup with coco coir.

In Part 1, our seedlings were only 5 days old, and just above the dirt. We fed these seedlings water with basic veg nutrients under 18/6 lighting.

In Part 2, our seedlings were 12 days old, but only about 4 inches above the dirt. Still a very tiny plant. We decided to give them one more week under 18/6 lighting before switching them to a 12/12 light cycle.

Now, our plants are 19 days old and we are going to put them under a flowering light cycle.

Why use the 12/12 light cycle from Seed?

The purpose of this experiment is to see if you can skip the vegetative light cycle and go straight to 12/12 from seed. Why would someone ever care to use only one period of growth for a photoperiod plant?

Time. That is why.

If you can skip an entire vegetative cycle, you get to flower your plants sooner, which means you get smokable herb sooner. And this is a legitimate objective for a grower.

How much time are you saving by skipping the 18/6 Veg cycle?

As we’ve discussed before, the vegetative stage can be 2 to 8 weeks or more, depending on the goals of the grower. At the end of the day, the indoor grower can control the veg period and make it really short or really long. But if you can skip it altogether, you no doubt will save time.

Typically, our plants spend 4 to 5 weeks in the Veg Room, under 18/6 lighting. However, that time is calculated from a potted clone. If you recall, our clones will spend about two weeks in the EZ-Cloner before we transplant them into a pot.

Once potted, we then start counting the weeks in veg, which usually amount to about four or five weeks total under 18/6 lighting.

If we are running with seeds (which we rarely do in our normal production schedules), we would add about two weeks to the amount of time spent in the Vegetative Stage. The reason for adding two weeks is that seedlings are tiny for the first ten days or so.

Why did we wait three weeks before using the 12/12 light cycle?

We initially decided to do an experiment of planting seeds in soil in red solo cups and then flowering them. However, it took close to a week for the seedling to even push above the dirt.

After a full two weeks, we still thought the plant was just too small to flower. These plants did not have anything you could call a “branch.” Instead, just small “leaf-lings” attached.

Yes, I know the purpose of the experiment is to see what happens when you use the 12/12 light cycle from seed. But we decided to wait another week.

Therefore, these plants spent a total of 19 days under 18/6 lighting. Does that ruin our experiment? You can be the judge of that.

At Day 19, we decided to flip the seedlings into a flower room under a 12-on, 12-off light schedule.

Using Red Solo Cups as the potting container for marijuana seedlings

Another variable in this experiment is our potting container. We are using a red solo cup, which is sufficient for the seedlings, but will not be for a flowering plant. That is our theory and we are going to test it.

What type of bulbs used for our 12/12 light cycle?

For this experiment, we chose to put the seedlings under our Agnetix LED lights. These lights are 1200 watts of full spectrum LED. The environment is a bit warmer, and a bit more humid. This creates the perfect “rain forest” like atmosphere.

So while the grow container might not be great, the atmosphere and lighting are as good as it gets for flowering cannabis.

Eight More Weeks of this Experiment

It’s been three weeks already, but our seedlings are now under 12/12 light schedule. It’s time to see what these red solo cups can do!

In Part 4, we will review our seedlings after their first week of the flowering period and see what changes can be observed.


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