Orange spots, low humidity

Below is my filled out questionaire. Growing in desert environment and my RH is WAY low. Thinking this may be causing mineral deficiencies but not sure which. Read mynamestich's sick plant guide and it looked like a couple of different probs could be happening related to humidity. My temps are a little high as well.



How long has this problem been going on?
2 days
What STRAIN are you growing?
CH9 mixed female
What was the establishing technique? (seed or clone?)
Seedling
What is the age of your plants?
12 days
How Tall are the plants?
+-6 cm, 2-3 inches
What PHASE (seedling, vegetative or flower) are the plants in?
Seedling
What Technique are you using? (SOG, SCROG etc)
N/A
What size pots are you using? (Include how many subjects to pot)
4 inch round
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?)
Local nursery brand organic soil no amendmants.
What Nutrient's are you using?
None
How much of each with how much water? How Often? *Knowing the brand is very helpful*
What is the TDS/EC/PPM of your nutrients used?
What is the pH of the "RUN-OFF"?
6.5-7
What method of pH test was administered? Using Strips? pH pen?
dropper liquid stuff
How often are you watering?
every other day
When was your last feeding and how often are you feeding?
What size bulb are you using?
250w CMH
What is the distance to the canopy?
+-30cm, 12 inches
What is your RH Factor? (Relative Humidity)
20%
What is the canopy temperature?
85F, 30C
What is the Day/Night Temp? (Include fluctuation range)
72F, 21C night
What is the current Air Flow? (cfm etc.)
Unknown, growing in closet until cab is built with 6-inch, 15cm desk fan on light and 16-inch pedistal fan blowing out of closet.
Is the fan blowing directly at plants?
partially
Is the grow substrate constantly wet or moist?
no
Is your water HARD or SOFT?
HARD
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
Tap PH'd to high 6s with white vinegar
Has plant been recently pruned, cloned or pinched?
no
Have any pest chemicals been used? If so what and when?
None
Are plant's infected with pest's?
no

Thanks in advance friends,

de Toke

Best guess is maybe you got some nutrients on the leaves? The lights can burn holes in the leaves where water spots... i've had it happen when using high P ferts

Thanks for the reply, Nav. Yeah, they've only gotten ph'd water so far. The organic soil's got bat guano and Kelp and other pretty goo stuff in it, but I don't think it is overly hot. PH seems okay too, although I'm not using a sophisticated measurement device, so can't completely rule out either.

I've got a similar weird tanish brown spot thing going on like your plant. It's just in a few spots on one leaf. I think for one I watered with too much liquid seaweed (new clones just planted in soil medium) and another i think i splashed some on the leaf, light could've burned it like Navigator says. Maybe your young one just has a special way of saying hello...it's probably not nute related like you say...

Thanks for chiming in, SH. What is your RH? I really think that has to be causing or related to my problem.

I don't believe it is a mineral burn from drying water spots because it started small and grew. Then I saw other little ones developing on the opposite leaf.

Maybe there's another low-humidity grower out there who knows more than me. I lived in so cal my whole life before moving to AZ, so this is new for me.

de Toke

IF you do think your RH is too low you can always add a cool mist humidifier during Veg. They will love it

Yep, Nav, you read my mind.

Actually just remembered that I got one in storage. I'll bust it out tomorrow and post an update...

de Toke

i think you're main problem is overwatering... if you are watering these little seedlings in such relatively big pots every two days, and the soaked look of your soil confirms this, then they are drowning and mis-absorbing nutrients... and the soil has little perlite to help provide aeration

other than that, the 85 temperature at 12 inches with a 250 CMH seems extreme... is the thermometer probe in direct light?... i run a aircooled hood 400 CMH at less than that, much less and they are chillin... if it really is the temp you might have to look into better heat controls as it will affect your grow

wygram said:

i think you're main problem is overwatering... if you are watering these little seedlings in such relatively big pots every two days, and the soaked look of your soil confirms this, then they are drowning and mis-absorbing nutrients... and the soil has little perlite to help provide aeration

other than that, the 85 temperature at 12 inches with a 250 CMH seems extreme... is the thermometer probe in direct light?... i run a aircooled hood 400 CMH at less than that, much less and they are chillin... if it really is the temp you might have to look into better heat controls as it will affect your grow

Click to expand...

Hey wygram, thx for stoping by.

You are right they do look soaked. I had only watered 'em about an hour before. I'm pretty careful about not over watering--the pots were getting nice and light in two days because of the temps and 18-20% humidity. I've actually brought the temps down a bit to 83, but the real problem is that they are in a closet corner and the air circulation is not optimized to say the least.

The good news is I think I found my problem. We got some pretty dang hard water here in my part of AZ. I thought that my PH was cool because I was adjusting with white vinegar testing it and letting it sit out for a day. What I didn't realize was that my naturally bufferific water had reverted to a PH of about 8!

So, I was basically locking out eeverything they needed to grow healthy, and I think I'll stop that now

I'll update soon with pics...

Thx again for trying to help everyone


de Toke

Well, I definitely found my problem. I know It's been a while since I updated but thought I would come back to wrap up the story.

the real problem wasn't so much my water PH as it was my transplant method. The seeds were started in Jiffy pots and then planted into the 4-inch containers. But I planted the jiffies deep in the pots in order to put soil around the lower part of the stretchy, elongated stems for added support. but that meant there was only about a centimeter of soil below the jiffy pot. I was hoping roots would grow more out of the sides. Instead they just circled the bottoms in a vain search for nutrients.

So, I broke down and went to the local Hydro-mart and got a $20 bag of FF Ocean Forest and transplanted into 1.5 liter sqaure pots. They started to look better within a day.

Three days after tramsplant:




1 week:



Seems like they want to really take off now (and after 4 weeks it's about time). So, I'll try to stay out of the way from now on...

Thanks to all who chimed in.

de Toke