Runtz Muffin Grow Diary and Strain Review

This diary covers my indoor run with Runtz Muffin from Barney’s Farm. I didn’t plan it as a full report at first, just kept notes for myself, but the plant turned out interesting enough to put the whole run together.

I’ve grown a lot of different genetics, and Barney’s Farm has usually been reliable for me. Runtz Muffin looked like the right candidate for a big photoperiod project: strong parent lines, good yield potential, and enough room in the box to really work the structure.

27 - 29% THC

Runtz Muffin (Barney's Farm)

• Photoperiod
• Smashing relaxing power
• 550 - 600 g/m² indoors
  1000 g/plant outdoors

Pack (number of seeds)

1

3

5

10

$36 $98.39 107.99 Save 9.6 $131.99 179.98 Save 47.99 $232.78 359.97 Save 127.19

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Starting the Run

Week 1-3

The first part of the grow was all about building a plant that could later fill a ScrOG properly. I started in soil and kept the early routine simple, letting the seedling settle before pushing any hard training.

Once the plant had enough growth, I started shaping it for main-lining. I wasn’t trying to rush height here. The point was to build a clean base with strong future colas instead of letting one central top dominate the whole bush.

Week 4-5

The plant took the early topping well, so I kept working on the frame. The structure became flatter and easier to read, which made the next training steps much more predictable.

I also started removing extra leaves where they were blocking light. Nothing too brutal at this stage, just enough to stop the middle from turning into a shaded mess.

Week 6

By week 6, the plant was ready for a more serious clean-up. I removed some foliage, then gave it a full day to recover before feeding.

The first proper nutrient mix was 2l (0.5gal). It included Sensi Star Grow at 0.2ml/l (0.03fl oz/gal), Bubble Zym V2 at 3.0ml/l (0.4fl oz/gal), Resine Plus at 1.5ml/l (0.2fl oz/gal), and Rhizoponics at 0.2ml/l (0.03fl oz/gal). The reaction looked fine, so I kept the plan moving.

Week 7

This week started with a transplant into a 25l (6.6gal) pot filled with AllMix. After the plant settled in, I put the ScrOG back in place and spread the colas into separate cells.

I bent the shoots down, trimmed a few leaves, and fed right after training. The mix stayed mostly the same as before, but Sensi Star Grow went up to 0.4ml/l (0.05fl oz/gal). AllMix already had food in it, but from experience I didn’t think a careful feed would hurt.

Veg Progress and Training

Week 8

Week 8 was when I decided to give the root zone more room. The plant moved into a 50l (13.2gal) pot, and that ended up being one of the biggest reasons this grow got as large as it did.

With more soil under it, Runtz Muffin started looking like a plant that wanted to take over the space. I kept using the screen to guide the branches and tried to fill the area evenly rather than letting a few tops race upward.

Week 9

The ninth veg week was longer than I usually keep a plant in vegetative growth. Normally, I would flip after 6 or 7 weeks, but this one had enough structure to justify waiting.

By this point, the ScrOG had done its job. The canopy was wide, the plant had many flowering points ready, and I felt it was finally worth switching to 12/12 instead of leaving unused space in the box.

The Flip and Early Flower

Flower Week 1

I flipped to 12/12 in week 10. Day temperature was around 27°C (80.6°F), and nights could drop to 15°C (59°F), so the room had a noticeable day-night swing.

The plant answered the flip with a strong stretch. I kept tucking shoots into the ScrOG and tried to stay ahead of the canopy before the branches got too stiff to move comfortably.

Flower Week 2

By the second flowering week, the plant was around 50cm (19.7in) tall. The screen still helped a lot, but I could already see that this wouldn’t be a small bush.

I focused on keeping the tops separated and removing leaves where they were blocking bud sites. The plant didn’t seem bothered by that kind of work, which made the whole training process easier.

Flower Week 3-4

Humidity sat around 46%, which felt comfortable enough for this stage. The flowers were still young, but the structure looked promising, and the many prepared tops started turning into visible bud sites.

At this point, the decision to veg longer started making more sense. The plant had a lot of places to build flowers, and I didn’t feel like I had wasted the extra time.

Flower Week 5-6

The plant reached about 100cm (39.4in), so the stretch had been serious. It still stayed manageable because the frame had been built early, but I had to keep correcting the canopy and watching the taller tops.

Bud development picked up properly in this period. The flowers started stacking better, and the plant looked like it was putting the big container to work.

Flower Week 7-8

The middle part of flower needed patience. This run took longer than the usual timing I’d expect from the strain, and I think the number of formed bud sites had a lot to do with that.

I kept cleaning up unnecessary leaves as the plant matured. By this point, Runtz Muffin was fully focused on flower production, and the earlier ScrOG work was paying off in a wide, full canopy.

Late Flower and Finish

Flower Week 9-10

The colors became much more interesting near the end. The plant showed rich purple and pink tones, especially as the final days came closer.

In the middle of the last week, I stopped watering and let the plant sit through a 5-day dry period before harvest. One day before cutting, I also left the bush in darkness for 24h.

Harvest

Since most of the foliage had already been removed before harvest, cutting the plant down wasn’t too painful. I divided it into large branches and hung everything to dry in the same tent.

The buds were dense, but drying still took only 4 days. I left some branches hanging for one extra day, then removed the buds with minimal stem and cleaned up the remaining leaf.

Runtz Muffin Yield and Final Thoughts

This ended up being the biggest Runtz Muffin plant I’ve grown. The 50l (13.2gal) pot really changed the scale of the run, but it also meant the plant needed more time to finish properly.

The final dry weight was 400g (14.1oz). Maybe I could have pushed it a little further with more precise measuring on the nutrients, but honestly, I was fully satisfied with the result.

The quality didn’t disappoint either. Even without a real flush, the buds came out aromatic and smooth enough, with no harsh throat scratch. The profile had a fresh pine note supported by a sweet fruity tone.

The effect was relaxing and very much on the evening side for me. It dried my eyes hard and often made me sleepy, especially after a long day. I’d keep this one for lazy weekends or the end of the night, not for anything that needs focus.

I’m happy with the genetics. Runtz Muffin asked for time and space, but in return it gave me a big harvest and flower I actually enjoyed smoking.

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