What is this on my basil?

TotalNoob

Hoping to get some insight as to what may be happening to my basil (lemon basil).

Plant is kept indoors and was sprouted from seed.

Nitrate = High (been battling this for a while)
Nitrite = 0
pH = 7.6
Water temp: 78-80

Still trying to figure out how to post images so, here is a link to the Imgur gallery with the pics.

https://imgur.com/a/yPsWYch

7341

Looks like heat stress.
See how the leaves have turned upwards on the edges.Dark marks are where they have burnt,were there white marks on the leaves before it went dark?

You said indoor,are you using lights?

TotalNoob

7341 wrote:

Looks like heat stress.
See how the leaves have turned upwards on the edges.Dark marks are where they have burnt,were there white marks on the leaves before it went dark?

No white marks at all. I use to have issues with chlorosis (yellow leaves, green veins) and that seemed to have been fixed by adding kelp extract.

Shortly after, however, i started getting the black sports. They do not precede any white spots and show up on old as well as new growth.

You said indoor,are you using lights?

Yes, using a 600w (i believe) LED. It is pretty high above the plants. Do you have any experience with grow lights? lf so, how high do you recommend they are above the plant?

7341

Yes only indoor.In this country you can't depend on the weather.Last week it was 8C/46F non stop rain but the 5 weeks before that it was 24C/75F - 28C/82F & full sun with no CLOUDS! (very rare here :lol:

)

It depends on how big the system is,is it enclosed,temperature & humidity.The lights should be at least 30cm away from the canopy (if it's LED of CFL.HID are a bit different.).
Are they real LED lights or some chinese replica?.
How long have you got them on for?.On & off period?

TotalNoob

7341 wrote:

Yes only indoor.In this country you can't depend on the weather.Last week it was 8C/46F non stop rain but the 5 weeks before that it was 24C/75F - 28C/82F & full sun with no CLOUDS! (very rare here :lol:

)
Those are some wild climate shifts you got there. I can see why you grow indoor only.

It depends on how big the system is,is it enclosed,temperature & humidity.The lights should be at least 30cm away from the canopy (if it's LED of CFL.HID are a bit different.).
Are they real LED lights or some chinese replica?.
How long have you got them on for?.On & off period?

System is indoor in my kitchen area. Temperature at home is 78 during the day. 74 at night. Because the setup is located in a large, well ventilated area, humidity is not really an issue (plus the air conditioner keeps humidity low in the house). System size is relatively small. 55gal fish tank. 20 some odd gallon grow bed.

I believe the LED are legitimate as they were a gift from someone who used it to grow, very successfully I might add, other plant types lol.

Currently, the lights are on for 12 hours 0600 to 1800.

Would heat stress affect the main stalk of the plant? I noticed some brown spots on the stalk itself.

7341

TotalNoob wrote:

System is indoor in my kitchen area. Temperature at home is 78 during the day. 74 at night. Because the setup is located in a large, well ventilated area, humidity is not really an issue (plus the air conditioner keeps humidity low in the house).

Lack of humidity would be the problem with heat.How low is the humidity?.

Can you post some more pics of the stem (could be a deficiency).

What's the Nitrate reading?

What are you feeding the fish?

Are the plants flowering?.For growth stage you will need the lights on for around 18 hours a day.12 hours is for budding/flowering.

Posting pics;
viewtopic.php?f=4&t=107

TotalNoob

7341 wrote:

TotalNoob wrote:

System is indoor in my kitchen area. Temperature at home is 78 during the day. 74 at night. Because the setup is located in a large, well ventilated area, humidity is not really an issue (plus the air conditioner keeps humidity low in the house).

Quote:

Lack of humidity would be the problem with heat.How low is the humidity?.

-~20-30%

Quote:

Can you post some more pics of the stem (could be a deficiency).

I actually pruned the plant prior to seeing this and cut off some of the stems that were showing issued. They had brown spots on them.

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What's the Nitrate reading?

- VERY HIGH. 160ppm is where my API test stops and the readings are definitely there. Interestingly enough, i did a recent water change (15 gallons of rain water, tank is 55 gallons in size) hoping that pH (7.6) and Nitrate would come down and...Nothing. I am very confused as i figured that replacing ~1/5 of the water would have some sort of impact

Quote:

What are you feeding the fish?

-NorthFin Premium Goldfish food. Fed every other day and just enough pellets for them to eat everything up and leave nothing in the tank. 4 goldfish total ~2-3 in in size each

Quote:

Are the plants flowering?.For growth stage you will need the lights on for around 18 hours a day.12 hours is for budding/flowering.

- I have not seen the basil flower at all, it does create new leaves when i prune it so it seems to be growing.

Quote:

Posting pics;
http://www.backyardaquaponics.com/forum ... ?f=4&t=107

- TY. Will read now!

7341

20-30% is very low,with 78F/25.5C temp the RH needs to be around 40%.When the humidity is too low,the plant drinks more & with huge amount of Nitrates,it can cause problems.

When there's too much Nitrate,the plants become soft & are more vulnerable to pests & disease and can cause nutrient lock out.
I hate the API NO3 test.I've wrote this several times on here,I could never get an accurate reading (says more than there is).But having 4 gold fish (I just read your other thread) will produce enough waste to power quite a few plants,so I believe your Nitrates are too high.

The lights need to be on longer for veg stage growth.I thought you may have been getting it to flower.

The PH,there could be some thing in the system causing the PH to stay high or maybe a lot of Carbonate.
Have you checked the KH of the water you usually top off with? & the PH? and of the aquaponic system? (KH).

TotalNoob

7341 wrote:

20-30% is very low,with 78F/25.5C temp the RH needs to be around 40%.When the humidity is too low,the plant drinks more & with huge amount of Nitrates,it can cause problems.

When there's too much Nitrate,the plants become soft & are more vulnerable to pests & disease and can cause nutrient lock out.
I hate the API NO3 test.I've wrote this several times on here,I could never get an accurate reading (says more than there is).But having 4 gold fish (I just read your other thread) will produce enough waste to power quite a few plants,so I believe your Nitrates are too high.

The lights need to be on longer for veg stage growth.I thought you may have been getting it to flower.

The PH,there could be some thing in the system causing the PH to stay high or maybe a lot of Carbonate.
Have you checked the KH of the water you usually top off with? & the PH? and of the aquaponic system? (KH).

Thanks for the feedback. I will have to look into the humidity issue you mentioned. At this point, i may have to build an enclosure around the grow bed to keep humidity in :think:

Quote:

The lights need to be on longer for veg stage growth.I thought you may have been getting it to flower.

I will adjust the time

7341

Something else,how big is the grow bed? meaning surface area?.600w is a lot!.
They say you need 40w per square foot,but if it's all leafy crops you could get away with 15-20w per square foot.

600w in a small area could be contributing to the leaf edges turning up (heat) with the air conditioning keeping the humidity very low.And if there's a strong breeze from a fan,that can make the leaf edges turn up too.

TotalNoob

7341 wrote:

Something else,how big is the grow bed? meaning surface area?.600w is a lot!.
They say you need 40w per square foot,but if it's all leafy crops you could get away with 15-20w per square foot.

600w in a small area could be contributing to the leaf edges turning up (heat) with the air conditioning keeping the humidity very low.And if there's a strong breeze from a fan,that can make the leaf edges turn up too.

Quote:

Something else,how big is the grow bed? meaning surface area?.600w is a lot!.
They say you need 40w per square foot,but if it's all leafy crops you could get away with 15-20w per square foot.

I am using a 27 gal. tote from Home Depot. Dimensions are 28.55 in. L x 19.61 in. W x 15.27 in. H.
The grow light is LED and hangs about 30 in. above the highest part of the basil. I have found that there is very little heat output from the LED Light on the plants themselves so I am not sure if that could be it.

May sound silly but if it is not heat, could it be too much UV or something the like?

7341

It's possible,600w is a lot.Surface leaf temperature is different to the air temperature.I read an article about that a couple of years ago,I'll find it & post the link.

The leaves that are turning up,are they the ones closet to the lights?.Or if not where? only on one side?

TotalNoob

7341 wrote:

It's possible,600w is a lot.Surface leaf temperature is different to the air temperature.I read an article about that a couple of years ago,I'll find it & post the link.

The leaves that are turning up,are they the ones closet to the lights?.Or if not where? only on one side?

The leaf cupping is pretty consistent across the plant both at the top (closest to the light) and at the bottom of the plant.

I am also noticing that the seeds that are beginning to sprout and have leaves on em are already yellow...

7341

I think it's something to do with the lights.
A about a year ago there was someone from Germany who had pretty much the same problem & he was using LED lights,seedlings died by wilting I think.But he never came back on,so I didn't find what the actual problem was.

TotalNoob

7341 wrote:

I think it's something to do with the lights.
A about a year ago there was someone from Germany who had pretty much the same problem & he was using LED lights,seedlings died by wilting I think.But he never came back on,so I didn't find what the actual problem was.

I hope it is something else since I am guessing the only solution would be to adjust the height of the lights and, unfortunately, I cannot go any higher lol.

Just out of curiosity and you may not know this but, I noticed that these 600w lights are very commonly used by folks that grow marijuana. The height at which they have their lights is usually pretty close to the plant and they raise it as the plant grows. Those plants seem to thrive with a 600w light so my question is, is a marijuana plant more resistant to light than herbs?

Just a curiosity.

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What is this on my basil?

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