SAFC Misfits: Homemade fertiliser trial (CBD Auto)

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SAFC Misfits: Homemade fertiliser trial (CBD Auto)
SAFC Misfits: Homemade fertiliser trial (CBD Auto)

Hello folks,

I'm coming into this a bit late as I'm growing in my unheated greenhouse (it was too cold to sow my seed much earlier).  I actually wet my seed on 16/5/23 and have been recording in a book and taking photos, but haven't been able to upload them until now.  I will add them over the next few days.

I'm very excited to be trialling a homemade fertiliser.  I thought it would be interesting to share this in the SAFC.  The fertiliser is made up of an A+B base nutrient, a Calcium + Magnesium supplement, and a Phosphorus + Potassium supplement (I still haven't made this last one but will do it in the next week).

My fertilisers have the following analysis:

A+B base nutrient

Nitrogen: 11.74% (of which Nitric: 10.16%, of which ammoniacal 1.58%), Phosphorus: 5.2%, Potassium: 12.6%, Magnesium: 4%, Calcium: 12.72%, Sulphur: 3.8%, Iron: 0.1654%, Boron: 0.0184%, Copper: 0.0046%, Manganese: 0.04%, Zinc: 0.0232, Molybdenum: 0.003%  

Calcium + Magnesium supplement

Nitrogen: 13.88% (of which Nitric: 13.18%, of which ammoniacal 0.7%), Magnesium: 5.76%, Calcium: 16.96%



Posted : 06/22/2023 3:28 pm Soil Sheppard, briguycny, LSLarf and 1 people liked

16/5/2023 (day 1) - Seed gets wet

  • 1x seed sown c. 0.5cm deep in Canna Coco Professional Plus.
  • Pot is 8cm plastic 
  • Pot watered once seed was sown by sitting it in a saucer of tap water and then spritzing over the top with more tap water
  • Tap water is very hard with an EC of c. 850uS (lots of chalk due to geology in local area)
  • Pot placed on west facing windowsill with glass Kilner jar on top which gets removed for 30-90 minutes a day (like a mini glasshouse)
  • Temperature over the next few days will fluctuate from 16.5-35 degrees Celsius
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Posted : 06/22/2023 3:43 pm Soil Sheppard and PuffyD liked

20/5/23 (day 5) - Seed germinates (success 😊 )

  • Seed germinated and tap water spritzed around seed to wash off any pieces of coco and get the seedling photosynthesising as soon as possible
  • Seedling moved to mini homemade grow tent (affectionately called the Salad Station v1)
  • SanLight Flex 10 (a 10watt LED) hung 11cm above seedling
  • PPFD tested with Photone App for iPhone using "Full Spectrum LED" addon which gave a reading of 230umol/m2/s
  • Light is on for 20 hours and off for 4 hours
  • Temperature range is 21-26 degrees Celsius 
Posted : 06/22/2023 3:56 pm Soil Sheppard, LSLarf and PuffyD liked

20/5/23 (day 5) - Same day again but TMI for one post (sorry)

  • Feed solution mixed up in RO water (background EC of 80uS) with 0.2g/L of A, 0.2g/L of B, and 0.3g/L of Calcium + Magnesium supplement
  • This resulted in a feed EC of 880uS and a pH of 6.4
  • This feed solution was then diluted down to 380uS and citric acid was added to reduce pH to 5.8 (the residual tap water in the pot has a high pH which is why I went quite low for the first feeding)
  • This feed solution was fed by sitting the pot in a saucer of feed solution for 45 minutes and some more feed solution was dripped into the top of the pot
Posted : 06/22/2023 4:06 pm LSLarf and PuffyD liked

21-5-2023 (day 6) - 24-5-2023 (day 9) - Increasing feed strength and applying foliar Calcium + Magnesium supplement

21-5-2023: EC increased to 510uS and pH of 6.3 (bottom and top fed). Foliar CalMag sprayed 2x per day at 550uS.

22-5-2023: EC increased to 620uS and pH of 5.9 (top fed only from now on). Foliar CalMag sprayed 2x per day at 550uS.  Run-off EC was measured at 570uS.

23-5-2023: EC increased to 720uS and pH of 6.0. Foliar CalMag sprayed 2x per day at 550uS.

24-5-2023: EC increased to 910uS and pH of 6.3. Foliar CalMag sprayed 2x per day at 550uS.

NB: Plant is being fertigated 1x a day at the moment.

Cannabis Grow 800 2967

Posted : 06/22/2023 4:23 pm Soil Sheppard, briguycny, LSLarf and 1 people liked

25/05/2023 (day 10) - 29/05/2023 (day 14) - Seedling developing nicely 🌱

  • Feed solution maintained at 900-950uS and fed 2x a day
  • Calcium + Magnesium supplement still being sprayed 2x a day at 550uS
  • Roots visible out the bottom of the pot were trimmed off to promote "side rooting"
  • Leaf clawing (suspected nitrogen toxicity) becomes evident on the third set of leaves
  • PPFD has increased to c. 265umol/m2/s (measured using Photone app with "Full Spectrum LED" addon

NB: I suspect that the possible nitrogen toxicity is caused by my foliar applications of Calcium + Magnesium supplement.  This supplement contains quite a lot of nitrogen.  I didn't observe any calcium or magnesium deficiency before beginning foliar application of the Calcium + Magnesium supplement (it was applied as a preventative).  For my next grow I will probably not apply this supplement as a foliar unless symptoms of deficiency are visible (or I may make foliar applications once a day instead of twice a day).  

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Posted : 06/23/2023 7:58 am Soil Sheppard, LSLarf and PuffyD liked

30/5/2023 (day 15) - Potting-up 

  • Potted-up into a 3 litre air pot
  • Growing media is same as for seed germination (Canna Coco Professional Plus)
  • No perlite was added, but it may look like there is some perlite in the photos as a small amount was re-used from a previous grow (its so little perlite that it's barely worth mentioning but just wanted to address this now to avoid confusion) 
  • Foliar applications of Calcium +Magnesium supplement have been halted due to leaf clawing (mentioned in previous entry)
  • Feed EC increased to c. 1010uS
  • Potted up plant placed back in tent under grow light
  • PPFD increased to c. 360umol/m2/s (measure with Photone app sing "Full Spectrum LED" addon)
  • Aqua Burst (wetting agent) is now being added to every feed at 1ml/litre

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Posted : 06/23/2023 8:26 am Soil Sheppard, LSLarf and PuffyD liked

3-6-2023 (day 19) - Moving out to the greenhouse ☀️

  • Plant moved out to the unheated greenhouse in my garden
  • Still feeding at c. 1010uS
  • Possibility of slight magnesium deficiency showing on one or two older leaves (but it's so faint that it could just be the way the light is shining so no action taken)
  • New leaves are not showing leaf clawing so I think that stopping Calcium + Magnesium supplement foliar applications has helped
  • Plant has started facing slightly south to make the most of the sun 
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Posted : 06/23/2023 8:47 am Soil Sheppard, LSLarf and PuffyD liked

4/6/2023 (day 20) - Some environmental stress

  • Some of the leaves are curling upwards from the edges
  • I think this is caused by two main environmental stresses (light and temperature)
  • Light: PPFD is peaking at around 1500umol/m2/s when measured with the Photone app "Full Sun" addon
  • Temperature:  Daytime temperatures are peaking in the greenhouse at c. 33 degrees Celsius and dropping to c. 9 degrees Celsius at night

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Posted : 06/23/2023 8:56 am Soil Sheppard, LSLarf and PuffyD liked

6/6/2023 (day 22) - Growing quite nicely 🌿

  • Plant has almost reached the 6th node
  • Still lots of fluctuating temperature and very high light levels
  • Plant looks to have gotten over the initial shock of being moved to the greenhouse
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Posted : 06/23/2023 9:04 am Soil Sheppard, LSLarf and PuffyD liked

7/6/2023 (day 23) - First topping ✂️

  • I'll be attempting to manifold this plant (I've never done this before and am a little concerned that the plant won't grow fast enough to achieve this because I'm growing in a greenhouse under natural light and without heating)
  • Plant is topped back to the third node
  • Feed EC increased to between 1150uS and 1250uS (it's a little different each time as the markings on my syringe are a little bit faded)

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Posted : 06/23/2023 9:13 am Soil Sheppard and PuffyD liked

15/6/2023 (day 31) - Second topping and training ✂️✂️

  • I couldn't see any pistils so decided to go ahead and attempt a second topping
  • The two stems (arising from the first topping) had barely reached their third node so I may have slightly damaged the buds (hopefully not 🤞)
  • Once the two stems had been topped, they were tied down horizontally (I had to soften the stems to do this without them snapping)
  • I didn't have any soft-tie so used what I could find (tent pegs, oh well 🎪)
  • Plant is now being fed 2x per day at 1150-1250uS

NB: Grow on the two main stems is not equal due to one stem being on the south facing side.

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Posted : 06/23/2023 9:43 am Soil Sheppard and PuffyD liked

17/6/2023 (day 33) - Settling in to its new shape 🟢🟨🔺

  • Plant has re-oriented it leaves and stems to make the most of the sunlight
  • Generally looking healthy
  • No obvious deficiencies or pests (at least to my eye)

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Posted : 06/23/2023 9:54 am Soil Sheppard and PuffyD liked
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19/6/2023 (day 35, flower day 1) - Flowering in "T" minus... 🌻

  • First sign of pre-flowers 

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Posted : 06/23/2023 10:00 am Soil Sheppard and PuffyD liked
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22/6/2023 (day 38, day 4 of flower) - Yellow veins of new leaves first thing in the morning 

  • I observe yellow veins of the very youngest leaves first thing in the morning
  • It seems to disappear throughout the day and start again the next morning
  • I think I see something similar on lots of plants

Question: Does anyone else notice this on their plants?  Thanks, Joe.

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Posted : 06/23/2023 10:10 am Soil Sheppard, LSLarf and PuffyD liked
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