is this light burn ?

[rkymtnman]

All three grows were fine until light was increased to 720

still dont' see light burn. see lots of burnt leaf tips though.

why would you turn it up to 100% on the 2nd or 3rd time if you thought it was light burn??

 

[GroBud]

still dont' see light burn. see lots of burnt leaf tips though.

why would you turn it up to 100% on the 2nd or 3rd time if you thought it was light burn??

Why I dont like showing bad parts of grows as reference someone always thinks differently. I didn't start growing yesterday lol I run perpetually indoors and outdoors as well which allows for these type of indoor experiments.

 

[rkymtnman]

Why I dont like showing bad parts of grows as reference someone always thinks differently. I didn't start growing yesterday lol I run perpetually indoors and outdoors as well which allows for these type of indoor experiments.

if you say so. maybe the 4th time it'll work for ya??

 

[GroBud]

if you say so. maybe the 4th time it'll work for ya??

Nope just tried everything I could before giving up on that light in that space. I was going to get a 5x5 but the watts per sqft is 28 watts per sqft running 720 watts but in the 4x4 running 540 @ 75% its 33 watts. See when you smoke 12oz a year but average 40 to 45 oz every 100 to 120 days alot of things dont mean as much.

My feedings are nothing until in new pot for 3 weeks for a auto and a month for photos. Normally plants are slightly fading on the bottom before 3 to 4 weeks. Veg I'll use 444 all purpose a tbls per gallon, veg to flower transition I'll use half 444 half 394 flower girl, flower I'll use flower girl. Each feed is Mixed with a cup of worm castings, humic acid tbls a gallon and azomite teaspoon a gallon. I'll water every 3 wks or so with fulvic acid. I'll also water with worm juice ( I have a worm bin ) fish poo, microbrew, kelp me kelp you, wholly mackeral and mycorrhizae in veg highly diluted. Flower I dont do as much besides top dress. I will make teas or give organic waterings when it's time to top dress to wash the feed in. Generally fulvic acid, worm juice highly diluted 300ppms or so, or mycorrhizae with molasses. But on the rare occasions of deficiency I'll also brew kelp meal, alfalfa meal, bat guano, sea bird guano, fish meal, or whatever the plant is needing, if still in veg I'll also give foliar sprays of what's nutrients are missing. I'll start seeds in happy frog since it has mycorrhizae, transplant into autos 20% top HF bottom 80% ocean forest. Thatll feed autos up to 2 months starting them in small pots transplanting at week 3. Photos in those same pots get a month then transplanted 5050 HF top OF bottom 2 gallons another month onto 5 to 7 gallons all OF thatll feed photos up to 3 months using tap, before any food is needed. My last top dress will be 6 or 7 weeks from harvest. I used ro for years stopped showing signs of calmag using tap hope that helps you decide if its nutrient burn or light burn. Especially being as the issue starts from the top after light strength change, with healthy green foliage bottom up.


Also I dont ph water if anything they should be locked out not nutrient burned that's over 2 months in 2 gallons of not phing water. If growing organically autos you'll never tell a difference photos will have higher ph around 4 months like 7.2 most I've shown at harvest is 7.7 after around 6 1/2 months still no lock outs keeping the microbes happy is key. I'll add the organic waterings probably help with soil ph since microbes ph water. Lastly yes there is slight nutrient burn, their 6 or 7 weeks into flower that's on every plant during flower unless you're withholding food, but wasnt this plants or any of the other 8 plants I tried running under that lights problem.

 

[thecannacove]

less infrared than HID, which heats plants in a specific way where plant leaves retain the heat. An HPS room at 80f would have plants that are 80f (or more) and an LED room at 80f would have plants at about 75-77f. although most new LEDs have added extra these days. I often wonder if thats a statement from the blurple days that never died but i dont know enough about light spectrums to confirm.

That's really good information to have. Thank you! I'm just starting to grow again after being out of the game for 8 years. Growing just 1 plant atm. Quality LEDs are much more affordable now so I thought I'd give that route a go.

The reason I looked up light burn and such in the forums is because my plant as a young seedling was exhibiting stress on it's leaves in a strange color. It was a purplish brown starting on the serrations of the leaves, then progressing inward to the margins. The only deficiency noted with these characteristics is a molybdenum def. But this didn't look like that was the cause, and it's rare to have that def anyways.

I began looking more closely at it, and it looked almost like a sunburn.. hence I looked up light burn as I remember it was a thing I had seen mentioned before. Anyhow.. I had my lights very close to my girl because the temperature at the tallest point was only like 78°F. I raised the lights and problem went away. Just transplanted her 5 days ago and she's very happy.

Also, you'll notice in the pictures where I was getting the light burn, that there are some necrotic leaves below. This little girl () started out decent but I didn't have adequate lighting at the beginning and I forgot to ph my water because I forgot the soil I started in, didn't have any lime to buffer it. Now that lighting is good and growing medium is on point, my baby is happy.

 

[thecannacove]

Exactly!

I switched from CMH to leds in the grow tent... But I have a fan that blows 24/24 to keep it odor free (negative pressure)... And plants went south from there... As soon as I bring back the cmh, everything was back on track... So if you grow using led, raise your room temp a bit, to get the leaves in the 75-78F range.

Sweet, I'll raise up temp to 80°F

 

[thecannacove]

I dont run hydro but I have had light burns on 3 different grows. Normally itll start out with top growth getting white tips then move to leaf edges then plants will droop and start fading could show nitrogen deficiency could show multiple deficiencies or just burns starting from top down. I'd go with advise given just ahead up on what to look for this is early signs of light burn. The second is the same plant about a month maybe more later. The third is another plant that was worse but made harvest. Tried running a ROI-e720 in a 4x4 as mentioned 3 times using different methods. In the last pic if you zoom in on the middle bud you can see the leaves starting to droop and are burned. Shoulda took more pics during this process but man it got ugly.

Thanks for the pics for examples. Mind taking a look at mine a couple posts back and see if you think that's what it was?

 

[GroBud]

Thanks for the pics for examples. Mind taking a look at mine a couple posts back and see if you think that's what it was?

It can have many different appearances including deficiencies to just burning depending on severity. It's hard to identify unless you know it's the light. First time I tested everything taking about 2 weeks to come to the conclusion that it was the light. I ran a different method each grow they all went south once light increased. Nothing you can do but adjust light and try to ride it out after about 6 weeks under okay light the leaves will start returning to green starting inside out. The survivors anyways.

I didn't read your post just looked at pics I'd check medium ph, earlier pics maybe I could tell more as mentioned it can have a variety of appearances. I've never experienced light issues on vegging plants. Even had on one plant every light available leaf show nitrogen deficiency even tho soil ph was 6.8 I had top dressed when that didn't help I top dressed blood meal when that didn't help I even made grow big ph solution just to try and get nitrogen to the plant, not in full doses but accordingly by what I had already given besides the initial top dress. Taking into consideration more light plants use more nutrients. None of that worked on leaves getting direct light. All leaves below canopy not getting direct light were green. Which is ass backwards if you understand where issues start. Environment or medium. I'll add in every case the first sign was praying, my sugar leaves would develop white tips, then growth receiving direct light would droop away from light.