🌱 Black Diamond Auto – Plant B | Week 4 | 12/12 From Seed
Another Diamond Begins to Show Its Shape 💎
Welcome back to another update from my 8×8 Adventure, where every plant gets the opportunity to tell its own story.
This is Black Diamond Auto – Plant B, the sister of Plant A. While they share the same genetics, the same environment, the same feeding schedule and the same light, it’s already fascinating to watch how differently they choose to grow.
Plant B has developed into a much more compact structure. She isn’t chasing height like her sister—instead she’s building a dense, symmetrical framework with tight internodal spacing and a very healthy canopy. Sometimes the smallest plants surprise us the most once flowering really begins.
Both plants are being grown under my favorite challenge: 12/12 from seed.
For those joining the diary for the first time, this means the plants have been under a 12 hours on / 12 hours off light schedule from the day they germinated. Instead of spending weeks in vegetative growth under 18 or 20 hours of light, they naturally transition into flowering much sooner, creating unique plant structures while allowing more harvests throughout the year.
Every run teaches something new, and this comparison between two sisters should be another interesting chapter.
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🌱 Environment
This week the room remained very stable despite the summer temperatures.
• Day temperature: 33°C
• Night temperature: 25°C
• Relative humidity: 63%
• pH: 6.1
• EC: 1.35 mS/cm
• CO₂: 639 ppm
The plants continue growing inside 15 L pots, receiving approximately 1.1 L of nutrient solution per day.
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💧 Hand-Watering vs AutoPot
Unlike her sister, Plant B is still being hand-watered.
Both plants receive exactly the same nutrient recipe, but the irrigation method is different. This should make for an interesting comparison later in the grow.
Hand-watering gives me complete control over when and how much solution she receives, allowing the substrate to go through gentle wet and dry cycles before each irrigation.
Her sister, meanwhile, is growing inside an AutoPot system.
The AutoPot uses an AquaValve, a clever mechanical valve that automatically opens and closes depending on the water level inside the tray. As the plant drinks, the valve refills the tray without pumps, electricity or timers, allowing the roots to take exactly what they need whenever they need it.
Will continuous bottom feeding produce faster growth than traditional hand-watering?
That’s one of the questions this grow hopes to answer.
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🌿 Training
No topping.
No supercropping.
No heavy stress.
This week has been all about Low Stress Training (LST).
Branches continue being gently bent outward to improve light penetration across the canopy while maintaining an even structure. Every day I spend a few minutes adjusting stems, leaf tucking large fan leaves and opening small windows of light for the developing side branches.
It’s amazing how much a few careful adjustments can change the architecture of a plant without causing any significant stress.
The goal is simple:
* create an even canopy
* expose future flowering sites
* maximize airflow
* let every branch earn its place under the LEDs
Plant B has responded beautifully, staying compact while becoming wider with every passing day.
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🌸 The First Signs of Flower
By the end of Week 4 the first pistils are finally appearing.
This is always one of my favorite moments in a 12/12 from seed project. The transition happens naturally, almost quietly, until one morning those first white hairs appear and you know the next chapter has officially begun.
Stretch is only beginning, but her structure suggests she’ll remain shorter and bushier than Plant A.
Two sisters.
Same genetics.
Same room.
Same nutrients.
Yet completely different personalities.
That’s exactly why I love documenting every individual plant.
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🍽️ Feeding
This week’s recipe remained simple and consistent:
• Terra Grow — 1.8 ml/L
• Power Roots — 1 ml/L
• Pure Zym — 1 ml/L
• Sugar Royal — 1 ml/L
EC remained at 1.35, with pH adjusted to 6.1 before every watering.
She continues responding with vigorous growth, healthy color and strong new shoots throughout the canopy.
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📸 Final Thoughts
Watching siblings develop side by side is one of the most rewarding parts of growing.
Plant A seems determined to become the taller, more vigorous sister.
Plant B is taking a different path—shorter, denser and incredibly well balanced.
Neither is better.
They’re simply expressing different sides of the same genetics, and that’s exactly what makes these side-by-side diaries so enjoyable.
The stretch has only just begun, flowering is officially underway, and I’m excited to see whether hand-watering can keep pace with the AutoPot system over the coming weeks.
Only time—and plenty of photos—will tell.
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🙏 Thank You
As always, thank you to everyone following this adventure from around the world.
To GrowDiaries for providing a platform where growers can learn from one another.
To Plagron for the nutrients that continue feeding this project.
To the incredible breeders behind Black Diamond Auto.
To the teams behind the LEDs, the equipment and every tool helping make this grow possible.
And finally, thank you to every person who stops by these diaries.
Whether you’ve been here since day one, discovered the journey this week, leave comments, ask questions, share advice, quietly read along, or even challenge my methods—you all contribute to making this project better.
Every interaction is another opportunity to learn, improve and keep growing together.
Growers Love and see you all next week.
Happy growing. 🌱💚