One of the most popular types of lighting for cannabis grows that’s gained popularity over the past few years is LED lighting. The first prototypes of LED lighting weren’t the best in as far as quality, especially when it came to flowering cannabis plants. Nowadays there are certain models that provide amazing results.
Like we were saying in our post Growing Cannabis with LEDs, Blooming LED panels allow you to give your plants the exact amount of light they need. This allows for more successful growing and flowering periods; you can easily adapt the light to your plants different needs in each stage of both growth on flowering. In this post we’re going to focus on flowering here.
LED Flowering – Flowering Stages
For a successful flowering period and in order to make the most of your light, you’ll need to adjust your LED lighting as your plants grow. This is especially important during the various different flowering stages of cannabis plants.
First Flowering Stage
This stage happens during the first couple of weeks after flipping your lights from 18/6 to 12/12h. If your plants are in the first flowering stage, have had a short growth period and are smallish or haven’t grown properly due to stress or other reasons, you’ll need to treat them with care; as if they were recently transplanted when it comes to light intensity – this requires around 10,000 lumens.
On the other hand, if your plants reach the flowering stage with a dense root system, are healthy and have grown out enough, you can start the flowering period at 25,000 lumens.
Second Flowering Stage
The second flowering stage starts the third or fourth week after flipping the lights. From the third flowering week onwards, your cannabis plants are going to want intense light in order to flower properly.
During this stage, cannabis plants tend to spend most of their energy producing new buds and cannabinoids, so you’re going to need to up your Blooming LED to the maximum (50,000 Lumens).
The distance of your LED panel from the top of your plants should be at least 30 cm so that light is evenly distributed among your plants, allowing for balanced results.
Third Flowering Stage
The third flowering stage falls between the fourth flowering week and 10 days before harvesting. During this phase when growing indoors, your plants are going to be fattening up their buds, so they’re still going to need quite a lot of light (50,000 lumens) to get it done.
The main advantage of growing with LED lights over HPS lighting is that it hardly lets off any heat, which allows your flowers to grow properly thanks to an even, adequate temperature. This also makes for less electricity usage compared to HPS or plasma lighting.
Plus, no excess heat means that your plants’ terpenes can grow properly (these are molecules that give your plants their flavour and aroma), and they won’t evaporate which results in a more aromatic and flavourful harvest.
Last Flowering Stage
In order for cannabis plants to properly mature and grow their buds properly, you’ll need to give them a “sign” that it’s almost harvest time. This is done during the last few days of the entire growing cycle.
There are various techniques that you can use around 10 – 15 days before harvesting so that your plant knows that it should start fully maturing.
- Wash out their roots and stop using fertilizers; this allows your plants to metabolize the leftover nutrients in the roots and leaves, and start finishing off their flowers.
- Lower the temperature; you can do this by adding cold air into your grow room or by using cold water the last few feedings.
- Lower the light intensity; the idea here is to simulate nature – when plants start noticing light getting lower, they’ll start maturing their cannabinoids (THC, CBD etc.). You should lower your LED panel by about 25% (around 35,000 to 37,500 if you were using 50,000) for the rest of the process.
Important LED Grow Information
All images using Blooming LED lighting were sent in by a La Huerta Grow Shop customer that started his first indoor grow with 2 Blooming LED panels for 1.2m square meters of growing area.
- Strain grown: Black Dream by Eva Seeds
- Substrate: Light Mix by BioBizz
- Fertilizers used: Pure Blend Pro Soil Bloom by Botanicare (during the entire flowering period), Bio Nova PK 13 14 (5th and 6th week), Carboload by Advanced Nutrients (5th and 6th week) and Cal Max by Grotek (in order to add Calcium and Magnesium, which distilled water lacks).
- Water: distilled.
- Grow size: 1.2 x 1.2 m
Blooming LED recommends using up to 3 panels per square meter; recommended if you want to harvest more than HPS lights (up to 700g per square meter using 3 panels) while using less electricity (480w overall, 160w per panel).
La Huerta Grow Shop
