Hi All, First grow here, and all was going well until mid flowering where things started to turn out different than expected. The buds that formed after the first couple of weeks have hardly gotten any bigger and the fan leaves have started to show brown spots all over, at first the brown spots were just on a or 2 of the lower fan leaves but over the past week it has spread across almost the entire plant, I have read that similar effects of the leaves can be normal as the plant cannibalises them to feed the buds but this seems more extreme than what I understand to be normal. I have been using Biobizz organic fertilizer in coco coir supplemented with CalMag on occasion. The plant was FIM'd once early on and was tied down as it grew to give it a flat bushy profile as I had limited height in the tent, there is some shade cloth to attenuate the light as it proved to be a little to strong for the the plant without it and the light can't be moved any higher. The pictures were taken 7 weeks and 3 days since I switched to 12/12 lighting. -Plant is 118 days old -Growing in Canna Coco Plus -Strain was a Hybrid "Mystery" -Grown Indoors -Lights are 450W Full Spectrum LED -Watered 1L a day with organic nutes, every 4th day just filtered water, skip watering if surface of coco still damp -Watered with a mix of tap water and filtered water -Pot size is 3 gallon fabric pots -About 15" from lights -Temps average 25c and range from 20c-30c (we have had some hot days recently and I don't have air conditioning) typical day temperature is 27c -Average humidity is 53.7 ranging from 62-39 depending on time of day and if recently watered. -No bugs Any input would be greatly appreciated.
The water around here is extremely hard so I have been using CalMag sparingly (once every 1-2 weeks), I will try increasing the frequency and see if i see any improvement.
I have been adding Cal/Mag on every feeding for the last week and they brown spots continue to worsen, they are now starting to show on the sugar leafs that were previously unaffected, bud size also remains unchanged. Any other thoughts on what could be causing this? and I assume it is to late into the flowering stage to save the volume of this harvest?
I see a bit of nute burn on the leaf tips. A reallly good flush with just water and cal/mag pH'ed , you might be getting lockout , what is your pH like?
I will try and measure it this evening, it is something I haven't really been keeping track of as the "Organic Nutes" I have been using (Bio Bizz) say that I don't need to PH them or water until runoff so I haven't been doing so for the entire life of the plant which was very healthy until it started to flower.
Did the coco coir have any info on the bag about buffering and the suggested pH ? The coco i use suggests a pH of approx. 6.0 , and keeping an eye on the ppms can help too. In coco you water with run off to stop the build-up of salts .
It says it is fully buffered and no mention of PH I can find, I Flushed the plant with 4 L filtered water and then added 1 L of filtered water with just Cal/Mag, the runoff was PH 6 as was the water applied measured with PH strips slimier PH shown by a pot meter shown on one of the pictures.. I waited a few days for the pot to dry out and added 1L of filtered water with Cal/Mag and half normal nutes and still find that the condition of the plant is worsening. Any more thoughts?
Looks like something is burning those leaves so either the light or the nutes but I thought biobizz was fairly week, do you have a way of measuring ppm? Considering you flushed now and should of got rid of any nute build up in the coco I would try moving the light up to 18 inches as ph sounds fine.
When it gets hot When it gets hot the plant uses more water, this causes the nutrient levels to rise in the pot, I would give it just plain water for a week or 2, and foliar spray with Brassinolide.