yellow leaves

[Altfuel]

Hi Guys...and Ms. Fox.
Got a newbee question...I have a small grow going with various strains (Indica dom). They are under 400 watts (hps) on 18/6 currently and moving to 12/12 this Friday. They are in FFOM and look very healthy. I live in the desert so temps are higher than most of you run. Up to 95 at the highest and 65 at the lowest. Humidity is an issue as well...16% up to about 35 % with a humidifier running full steam. Ventilation is more than adequate. I water when the plants tell me to and am using Dutch Master veg 1 & 2 at 1/4 strength about every third water. The tallest lady (I hope) is 11 inches and the shortest is 4.5 inches. The issue is the bottem set of leaves on each plant turns light yellow, gets crispy, then falls off. The tallest plant has gone through this 3 times in it's 7 week life. Secondary growth seems unaffected as do the leaves further up the plant. Is this nute burn?? Any clues would be greatly appreciated.

Alt


Bored enough to make stuff up....

 

[Hightide805]

Sounds too hot, I'd be sweating with those plants if I was sitting in a room at 95 all day... 72 to 76 is optimal, and 5 or 10 less at night. (flower cycle)

nutriets sound ok, on seeds I start after 2 or 3 sets of true leaves (female clones is the way to go if you can)
humidity is good at 50 more or less

good luck

 

[L8tNightSkunk]

hightide805 is right 95 is way too high, you could have some heat issues, the way i look at it when it comes to the temp is i try to figure out a temp where i would be comfotable not to hot or not cold right in the middle if im comfortable with it i know that the plants are going to be too

 

[Racefan]

If it starts at the bottom and works up its a nureient def. if it starts at the top it's a heat prob. You are either not feeding enough or your ph is off and causing nutrient lock out because you describe a perfect nitrogen deficient plant.

 

[Altfuel]

Thanks for all of the direction Guys. I tend to agree with Racefan, because it is always the bottom set of leaves. Everything the rest of the way up the plants look just fine. While it has gotten warm in the room, it only hits those temps for a short time. I have altered the light cycle so that they are on during the coolest parts of the day. Top temp is about 88 now. Not ideal but better. I was trying to get through the first grow w/o worrying about PH. Every rookie makes mistakes and this may be one of mine. I will go get a ph kit tonight and check it out.

Still don't know what to do to increase humidity...we are at about 9% outside and I have a hard time keeping it above 20% with the humidifyer going full speed. I have also put a open pan of water in the cabinet...any suggestions?

Thanks again.

Alt

 

[Altfuel]

What should the Ph of the nute solution be ideally? Also, what do you use to raise/lower the PH?

 

[Aussiebonger]

I found when i turned down the exhaust fan a bit humidity increaced, but i dont have heat issues. increase cool air in, reduce exhaust and humidity should rise. easier said than done i know...... good luck.

 

[Aussiebonger]

Or hang a damp towel in there dude....

 

[carolinagrow]

In Vegas, I would hang 4 or 5 wet towels in the grow area, basically everywhere that I could. Believe it or not but this raised the humidity better than anything else. Of course, it seemed like I was always hanging new towels because they would dry out so fast.
Hope it helps.
One other thing you might try is CO2, if you can't get your temps down to ideal (and I know that it might be impossible to do in the summer in the dessert), if you raise the CO2 level your plants can handle the heat much better. I came across a product on the net the other night that seemed very intriging called CO2 Boost or Booster or something like that. My local grow store has it in stock too. It is designed to raise your CO2 level by using natural products and you don't have to spend a fortune buying all the typical gear. Not designed for large grows, but for smaller ones, like 5 to 10 plants tops. I haven't tried it yet but was thinking that I would on my next grow since by the time I found it, I was almost thru with vegging.
Good luck

 

[OldSkoool]

Just the info I was looking for. You guys are great. I have 3 plants growing into their 4th week, two plants have bottom fans turning yellowish, the 3rd plant looks normal. All 3 share the same type of soil (african violet mix), CFL lighting, and de clor tap water. After reading these solutions I'll start a weak veg nute, hang some wet towels, and cut down on my air flow.

Thanks again for the help.

 

[Mongo100]

Ideal pH for soil matrix is 5.5-6.5. Also, what kind of light are above your plants? Use very small amounts of the pH up and down!

 

[OldSkoool]

Update

Racefan was spot on, but I was soooo wrong. I'd used two different African Violet soil types, assuming both were the same. The plant without any bottom yellowing leafs is growing in Schultz's with time release nutes, and the two plants with yellowing leaves were planted in Farard's...no nutes. Duh. Began a weak nute feed last week on all three plants, and it's all good now. Worth mentioning, the nutes (Miracle Grow Tomato) was premixed, and left over from my last grow 3 years ago. My only problem now is space to veg all three.

Thanks again for the info Racefan