Help

[whitlow]

Problem:
Spots on some of the leaves

Medium/grow method:
OF/perlite 75/25%
Feed: and supplements used:
Fox Farm Trio
Big Bloom 3tsp in 2gal
Tiger Bloom 1.5tsp in 2gal
Always pH to 6.4-6.8
I just started molasses 2tbl in 2gal water

water source:
Well water TDS 130

Strain/age:
Cotton Candy Kush
52 days

light used:
Ionboard S24 200W full-spectrum grow light with Samsung LM301B LEDs.

Additional info:
I feed evey 3rd waters
Plain water
Water with molasses
Always pH to 6.4-6.8
In on 18/6 light cycle 600-800 par
Temp are always high 77-94 degrees
RH hight 60-85%

 

[whitlow]

 

[MIAutomatic]

Have you added any calmag? Do you know what the mineral components of your well water are? A good part of that 130 ppm could be calcium and magnesium, but it could also be iron or sulfur or a number of other things.

94 degrees is hot and the humidity is consistently too high so your VDP is all over the place. How long are you at that temperature and what can you do to get it down a bit? Even if you are able to keep the plants healthy to harvest with temps and humidity that high it will have a negative impact on your terpenoids and encourage mold growth, the heat is literally cooking them off the plant. Heat stress can look a lot like some nutrient issues so getting your temperature and humidity down is where I would start. Raise the light or turn it down, crack the tent or room, add more ventilation and make sure air is circulating above and below the canopy.

Getting PH and PPM from some runoff would also be useful and the next step after getting your environmental conditions in better shape.

 

[whitlow]

I have done all I can to get the temps and humidity down. I have not had my week water tested but I'm checking in to doing it. I never have any run off I will increase the amount of water to check it next time. I tried some Cal-mag in 2 of my watering a few weeks ago when I saw it the first time on a older big bottom leave. Then I read so much about and how it shouldn't be used much. Like I said I'm a new grower so I'm trying to learn..

 

[MIAutomatic]

If you really can’t get the temperature and humidity down then I would not grow inside during the summer months. Plan you cycles so you finish by mid to late May then wait till fall or late summer to start a new crop. You can get plants across the finish line with this conditions, but they will not reach their potential. With humidity that high the chances of mold in the last weeks of flowering is also high.

Calmag might not help, your well water plus the soil probably has enough but testing is the only way to know for sure. The environmental conditions really do make it hard to pin down an issue, but more PH and EC date will help. Temps as high as you have start to limit the plants ability to photosynthesize and that has a chain effect on all of the plants processes and can create a range of symptoms that can look like a number of issues.

https://www.autoflower.org/threads/ultimate-vpd-guide-and-calculator-chart-maker.67979/

Check this out to get the basics of VPD.

 

[whitlow]

I was talking to my wife and told her I was going to start another grow after this and then start one in early spring like you said. I just never thought about it I was thinking about what I needed to grow and learn. So you think the way my leaves are showing is from any of this? And I hope I can finish this grow with something worth smoking!

 

[MIAutomatic]

Those plants look good overall!
Nice job on your first grow and you should definitely be able to get them across the finish line, I should have said that first.

I would mostly keep doing what you are doing. Next watering water to 15-20% runoff this way: slowly water until you get about 10% runoff, check this if you want but since you have not been watering to runoff it is bound to be quite high. Let the pots sit for 10-15 minutes to make sure everything is well soaked and there are no dry pockets of soil. Now water slowly until you get about 10% additional runoff.

When using any salt based fertilizer it’s a good idea to water to runoff at least occasionally. Even feeding lower doses can cause salts to build up at the bottom of the pot and while most of the soil will be healthy the bottom of the pot can become toxic to the roots. This doesn’t always happen, but it can happen depending on how much you are feeding and how well developed the plants root system is. This is less likely to be an issue with a large plant that has a well established root system.

 

[whitlow]

So on my next grow I'm going to water with molasses once a month. And then the next watering I will water till run off. Followed up with a watering with nutes. That will be the change from my first run as far as watering and nutes go. I've been watering .5gal I might go more to 3/4gal or 1gal to get some run off every time.