abmgrow
- 4
- 1
Hi everyone,
I am looking for some help diagnosing my plants.
I started these four plants from seed and they are 5.5 weeks old.
They are about a foot tall and growing in 5"x5"x5" plastic containers in a 70% seed starter/30% perlite mix. The seed starter is mostly peat moss with some vermiculite, lime and coco coir. I didn't feed them anything for about 3 weeks so they were probably a little bit stunted but I have started using FOOP organic biosciences nutrients and they have grown a bunch since then. At first all four seemed to be doing good, but now some are showing brown spots and interveinal patches of dead tissue.
Only three of the four plants are showing these symptoms while the third looks pretty nice but has some clawed leaves. I have noticed the tips have burnt on pretty much all of them and I suspect I might be over feeding even though I am feeding them less than the recommended dosage of FOOP nutrients. I feed them every time I water which is what FOOP recommends but I feed them the dosage for a 3 week old plant. The water I have been using is a 50/50 mix of local tap water (which is very hard water) and distilled water and I pH it to ~6.4. I've been watering/feeding them every 2-3 days. I measured the pH of the runoff from the worst plant and it read 5.6 but I've heard that measuring runoff directly can be an inaccurate representation of soil pH.
My theory so far is that it is a calcium deficiency but I don't know. I've heard that low pH makes it hard for the plant to uptake calcium and the low pH of the runoff would seem to indicate that I have a low soil pH. I don't think it is a problem of not providing the calcium needed for the plant because I am watering with diluted tap water but it should still have pretty high calcium content because it is so hard. I've also read that calcium is relatively immobile so I should be noticing the deficiency in the newer leaves but it only shows up in the leaves a few nodes down and below. I also find it strange that only 3 of the plants are showing these symptoms. The seeds are definitely not very genetically similar so I guess that could account for the difference.
Here is some other info:
- the FOOP nutrients I've been feeding are a 2 part system with a 1-0-0 nutrient ratio.
- No foliar sprays applied.
- I'm using a BEST VA LED grow light https://www.bestvaled.com/products/59495159419191
- The light is between 14-18" above the canopy.
- The temperature and humidity stay around 77F and 35% humidity.
Any help diagnosing this would be really appreciated. What does it look like to you?
I am looking for some help diagnosing my plants.
I started these four plants from seed and they are 5.5 weeks old.
Only three of the four plants are showing these symptoms while the third looks pretty nice but has some clawed leaves. I have noticed the tips have burnt on pretty much all of them and I suspect I might be over feeding even though I am feeding them less than the recommended dosage of FOOP nutrients. I feed them every time I water which is what FOOP recommends but I feed them the dosage for a 3 week old plant. The water I have been using is a 50/50 mix of local tap water (which is very hard water) and distilled water and I pH it to ~6.4. I've been watering/feeding them every 2-3 days. I measured the pH of the runoff from the worst plant and it read 5.6 but I've heard that measuring runoff directly can be an inaccurate representation of soil pH.
My theory so far is that it is a calcium deficiency but I don't know. I've heard that low pH makes it hard for the plant to uptake calcium and the low pH of the runoff would seem to indicate that I have a low soil pH. I don't think it is a problem of not providing the calcium needed for the plant because I am watering with diluted tap water but it should still have pretty high calcium content because it is so hard. I've also read that calcium is relatively immobile so I should be noticing the deficiency in the newer leaves but it only shows up in the leaves a few nodes down and below. I also find it strange that only 3 of the plants are showing these symptoms. The seeds are definitely not very genetically similar so I guess that could account for the difference.
Here is some other info:
- the FOOP nutrients I've been feeding are a 2 part system with a 1-0-0 nutrient ratio.
- No foliar sprays applied.
- I'm using a BEST VA LED grow light https://www.bestvaled.com/products/59495159419191
- The light is between 14-18" above the canopy.
- The temperature and humidity stay around 77F and 35% humidity.
Any help diagnosing this would be really appreciated. What does it look like to you?
