Red leaves: why?

[luvrin]

I have a 36 day old Northern Lights growing in potting seed raising mix with lots of perlite (and about an inch or 2 of coco peat on top because I stupidly repotted without checking to see if I had enough soil, argh!) I use a random fertiliser I have already in the house every 2 weeks or so (Maxicrop seaweed plant food). I water every 5-7 days. Ph sits at about 6-6.5. I have only recently potted up from a 2.2L to an 8L, and since then have had to put the plant in a different location due to size. It's now sitting in a closet (with door open) and I use 2x 30W grow LED lights, about 6" from the plant. Because of the new location, the temperature has dropped to 13°C at night and sits at about 18°C-21°C during the day. Light schedule is 18/6. Why are the new leaves turning red? Too cold? Too much light? (Before changing location I was only using 1x 30W grow LED light.) Do I need to feed her more, or use a more appropriate fertiliser, such as one designed specifically for cannibis? I'm at a loss and worried for my plant

 

[Allen42]

Overall, the plants looks rather healthy, I’m sorry my expertise are limited on this subject. If I had to take a wild stab in the dark I’d say early stage molybdenum deficiency... or it could just be the strain, also I just noticed your temperature issue, colder temps tend to bring out colors in our plants so maybe it could be as simple as that. I’m just throwing some cards in the hat at random lol you really need @Emilya in here to take a look, she’s extremely knowledgeable, so just wait for her to make her rounds.

 

[HugePeckerhead]

More then likely the strain. Plants look healthy overall.

 

[Old Salt]

I have seeds, but haven't grown this strain yet. Searching online, the images I found don't show purple stems or petioles, so you have a problem or a different phenotype(substrain).

You can find a download for Jorge Cervantes' 'Cannabis Nutrient Deficiencies and Excesses' with a Google search. Looking through the symptoms, purpling of the petioles (leaf stems) is often due to insufficient phosphorus.

Cannabis requires certain proportions of nutrients. You would be much better off with nutrients formulated for the plant. I've used the General Hydroponics' Flora Trio and supplements in the past, with coco/perlite. I switched to Mega Crop for my current grow, and it's working well so far. Mega Crop is probably the lowest cost option for cannabis fertilizers, costing less than a single component of the Flora Trio for a grow. It's also good for all forms of growing, so your soil/coco will work with it.

Something else you need to know is that coco coir has no useful nutrients. Roots will take the path of least resistance, which is your coco coir layer on top of your soil. If you can, remove the soil and coco you added when you up-potted, and mix them together. Your plant will thank you.

 

[BedroomFarmer]

I have a plant that does that, The buds turn purple. What's your night temps? Turning colors could be from too cold at night or just the strains genetics. If it's from too cold it will stunt the growth a bit.

 

[luvrin]

Old Salt, thank you! I'm going to do a Google search and see if I can find relevant information on it. Not sure if I can mix the soil and coco... won't I be disturbing the roots? It's all stem that's burried in the coco, I just wanted to cover up as much as I could. One small corner didn't have enough soil when I filled up the new pot, which is why I used whatever I had on hand. I'm going to make a few purchases for proper nutrients very soon. I'm just researching the products available here, as I'm not familiar with any of the ones you've mentioned (I'm in Australia). Thank you very much for your insight! PS - I still don't know how to reply to people properly without quoting them?! Sorry!

 

[luvrin]

Rich Farmer, last night's temperature dropped to 13°C in the grow closet. I only noticed the red leaves today upon inspection (I check her daily). She had no red on the leaves yesterday, but she has had the red stems for a few weeks now. I'm hoping you're right and it's just a bit chilly for her!

 

[NOOOBIENOT]

i would say temps are your problem as at cooler temps and large temps swings between day and night it makes it hard for the plant to take in phosphorus hence the purpling .Other wise i would say your plants look very good , work on the temps .

 

[volksball]

Rich Farmer, last night's temperature dropped to 13°C in the grow closet. I only noticed the red leaves today upon inspection (I check her daily). She had no red on the leaves yesterday, but she has had the red stems for a few weeks now. I'm hoping you're right and it's just a bit chilly for her!

Grab yourself a little spot heater. I use mine when the lights go out. It brings up my basement temps. I try for 26-27c during lit hours, and 22-23c during dark. Like mentioned, 13c may be your problem here.

 

[Allen42]

I agree, 55 degrees is just way to cold. I’m willing to bet if you stabilize your environment you’ll see significant improvement in your plants condition.

 

[Old Salt]

Old Salt, thank you! I'm going to do a Google search and see if I can find relevant information on it. Not sure if I can mix the soil and coco... won't I be disturbing the roots? It's all stem that's burried in the coco, I just wanted to cover up as much as I could. One small corner didn't have enough soil when I filled up the new pot, which is why I used whatever I had on hand. I'm going to make a few purchases for proper nutrients very soon. I'm just researching the products available here, as I'm not familiar with any of the ones you've mentioned (I'm in Australia). Thank you very much for your insight! PS - I still don't know how to reply to people properly without quoting them?! Sorry!

You will disturb the roots a bit, but the plant will recover. I cut through the roots if the plant has become root bound in the smaller pot. They come back stronger after a week or so. One of the plants I treated this way yielded 12.4 oz during my last grow. The others were strains that normally have a lower yield, or were used to produce seed.

Shipping to/from Oz is very expensive, you may want to use something else made locally for your nutrients. I'm in Canada, so it's not so much of a concern.

This is how the default alerts work:

1. When you start a thread, or respond to a thread, you will get an alert every time someone else responds to the thread.
2. Quoting a member is a very good practice in a busy journal, where there are one or more posts between your reply, and the post you are responding to.
3. Tagging someone by putting an asterisk before their name in a post, sends an alert to that member. This is normally used when the person you are trying to contact has not responded to the thread yet.
4. Mentioning the person's name in a post does not alert them, unless they are participating in a thread.

I'll tag you from a contest thread so you can see how this works.

 

[Emilya Green]

I am actually a little concerned about the coloring in the new growth as well as the red stress indication on the stems... this is a nutrition problem. The soil you are using has nothing and the fert you are giving is pure nitrogen, but your plant needs much more than just that, already. Get this plant into some real soil and heed the advice to get a full range nutrient in here, fast. I am also going to suggest MegaCrop... it is cheap and highly effective.

 

[Virgin Ground]

Yup, too cold. Get that room above 18c.
Anything below 18c(64f) plant processes shut down and magnesium won't be taken up by the plant.

 

[bobrown14]

There's a phyto-virus in Cannabis that starts with red coloration followed by leaf twisting and more purple on new growth.



As far as nutrient deficiency, hard to call. Plant color can come from genetics.

I grow plants that turn black. Its perfectly normal.

I also grow plants that stay green

I also grow plants that turn completely yellow.

In my case its genetics.

Phosphorus deficit usually starts at the btm of the plant and works its way up. Pretty early to tell if there are any issues. Time will tell. Plant looks pretty healthy so I'd leave it grow and see what happens.

Night time temps are well below optimal. IF the root zone is getting that cold the soil takes a while to warm back up to room temps so its getting a longer that room temp dose of cold. I'd put a layer of solid insulation under the pots to isolate them from the floor (that stays colder that room temps). Try improving the environmental conditions first. They are the easiest to fix and the easiest to reverse. Not so much with any other changes

 

[Elvin]

I'm pretty sure "Random Fertilizer" is your problem.
Emilya's suggestion is really the one you need to work on. Of course, get some heat in there, but you need some real nutes and Mega Crop's "free" 500g sample (you pay shipping) is a great suggestion to get you started.

 

[luvrin]

Wow! So many responses. I thank you all for your input. This isn't relevant, but I'm a female, so reading the posts saying "he" made me giggle. Anyway, I would agree with everyone that I will need to up the nutes. Being in Australia I find it hard to find what most people recommend on other threads so I try to find similar products. I've only just started so learning as I go, and things like PPM and lux and all that do confuse me. I'm trying to keep it simple. I know plants need water, a growing medium, and light... that's about the extent of my knowledge.

@Emilya (did I do it right?), would using products such as Richgro organics potash, potassium (made of guano), dolomite lime etc be beneficial or am I better of just going to a hydro store and buying those A+B products? I really don't want to have to spend more on a large amount of product as I only have the one plant, and I figured I could use the Richgro stuff on my other household plants as well.

I know that cold is a problem. Would using a heat mat be ok while we are experiencing cold weather, or should I use a heater? Prior to the 13°C drop, the night temp was a constant 19°C and day temp ranged from 23-29°C. Where I live, it should be warm consistently now but for some reason we've had cold weather come in and it will stay this way for a week before the weather warms up again.

Btw, the ph is tested from the runoff water. Should I be testing beforehand too? Would it make any difference?

 

[Emilya Green]

Wow! So many responses. I thank you all for your input. This isn't relevant, but I'm a female, so reading the posts saying "he" made me giggle. Anyway, I would agree with everyone that I will need to up the nutes. Being in Australia I find it hard to find what most people recommend on other threads so I try to find similar products. I've only just started so learning as I go, and things like PPM and lux and all that do confuse me. I'm trying to keep it simple. I know plants need water, a growing medium, and light... that's about the extent of my knowledge.

@Emilya (did I do it right?), would using products such as Richgro organics potash, potassium (made of guano), dolomite lime etc be beneficial or am I better of just going to a hydro store and buying those A+B products? I really don't want to have to spend more on a large amount of product as I only have the one plant, and I figured I could use the Richgro stuff on my other household plants as well.

I know that cold is a problem. Would using a heat mat be ok while we are experiencing cold weather, or should I use a heater? Prior to the 13°C drop, the night temp was a constant 19°C and day temp ranged from 23-29°C. Where I live, it should be warm consistently now but for some reason we've had cold weather come in and it will stay this way for a week before the weather warms up again.

Btw, the ph is tested from the runoff water. Should I be testing beforehand too? Would it make any difference?

I love it when more info comes in. Now I can confidently say that you have a pH problem and that this is the major cause of all the ugly stuff going on. So yes, you must adjust the pH as the last thing you do right before applying a fluid to your soil. The runoff pH or PPM tells you absolutely zero in a soil grow. Zero. It is a total and complete waste of time to even think too hard about your runoff... it is sludge akin to coffee out of a percolator... the more you flow through, the weaker it gets. At what point, 1%, 5% or even 20% runoff does any number you can get out of it mean something in regards to what is going on in the soil above? The answer is never... measuring runoff is a hydro/coco thing and is a valid measurement there... but not in soil. Not ever.
So when you went to the 8L containers, what soil did you use? I missed that somewhere, but I assume you used a good soil. If that is the case, all we need to do is get your pH in line and you are going to be well on your way to solving this. The cold is a thing, but our plants are tougher than that... I knew I was looking at a larger problem. I grow in a basement that we don't heat as well as the rest of the house, so I use a thermostat controlled space heater in the grow tent to keep things where I want it.
The Richgro is not an overall blooming nute and I seriously doubt you need to adjust a good soil with more lime. Especially with your experience level, I don't think I would recommend you trying to amend your soil with guano and other raw nutrients and expect to produce an organic grow based on that incomplete mineral additive list... you just aren't ready for that yet. Get into one of the nute lines and get through a grow to learn the basics....
Again, the new MegaCrop product is all the rage right now and I think it is a very good system to easily grow pot. It is cheap too... I just don't know if you can get it down there in OZ. Another good cheap alternative is Jack's, and he is good about recommending exactly his products that are needed for cannabis. Or you can go with any of the various liquid nutrient lines available in the grow shops. It all depends I guess on how much you want to spend and how much you trust the current crop of grow experts on the forums.
____________________________________________
The Proper Way to Water a Potted Plant (in soil) - STICKY
Emmie's Links, Journals and Tutorials
Berry-D'licious No AACT Organic - Grow Journal
Pineapple Chunk Mega Crop Test - Grow Journal

 

[luvrin]

Ahh, thank you for that @Emilya ! I'll have a look online for what you're recommending, but if I'm not able to get it, I'll visit my local hydro store. I know they have all the products there. I can grow more, I have plenty of seeds so it wouldn't be such a waste. Reading what you've written about the ph is all very new to me and it does make more sense when you explain it like that. I'm looking forward to when I need to feed her next! She's sitting in the same seed raising mix with perlite in the 8L pot, with the coco on top and in one corner. With soil, I'm not sure which one is good to use here in Australia so I figured that by using a seed raising mix, it shouldn't be a hot soil that everyone says to avoid. So now I'm assuming that it's NOT a good soil to be using for this stage of growth? I do have an organic soil I can use but on a different house plant, all these little flies were coming out of it and even mushrooms were growing. I was a bit grossed out by it and don't want to use it for the risk of those tiny flies appearing again.

I'll test the ph water before feeding with proper nutes next time, and adjust if need be. Should I then just sit and wait to see what happens? I've just checked on the plant and she's growing quite fast still. I've included pics just in case you can spot something new.

 

[Emilya Green]

for now keep giving the nutes you have been... its keeping it alive... but yes, order better stuff soon. Now you know that this starter soil is definitely not going to be able to feed your plant by itself.
You know those hot soils that "everyone" says to avoid... sometimes you just can't believe everything an armchair expert has to say on an online forum. As you have seen, some have some very strong opinions, and many times what you read is totally wrong. Don't trust the folks at the hydro shops either... they secretly want your soil grow to fail so you decide to buy a bunch of expensive hydro kit.
But this being said, you can get through this just fine by feeding the plants from a bottle. You will be fine. Next time though, you might want to try a stronger soil.
____________________________________________
The Proper Way to Water a Potted Plant (in soil) - STICKY
Emmie's Links, Journals and Tutorials
Berry-D'licious No AACT Organic - Grow Journal
Pineapple Chunk Mega Crop Test - Grow Journal

 

[Old Salt]

should I use a heater?

Definitely. I use a small space heater in my tent to keep it above 16°C / 61°F when the lights are off. When the lights come on, the temperature rises to above 22°C / 72°F. Growth is a little slower than with temperatures a few degrees higher, but I can accept that.

For nutrients, just be aware that many of the manufacturers and hydro shops are out to empty your wallet. I started with General Hydroponics' Flora Trio. The four basics (CALiMAGic, Flora Micro, Flora Grow, and Flora Bloom) cost about $80 CAD. I added about $250 CAD for supplements (Rapid Start, Floralicious Grow, Floralicious Plus, Liquid KoolBloom, Dry KoolBloom, and Flora Kleen). This is not the most expensive line by far. It also takes a lot of attention to detail to mix these into nutrient solutions properly.

I'm in agreement with Emilya, that Mega Crop is a low cost, easy fertilizer to use. Some folks are reporting problems, and they are being addressed by a group of us. I suspect that many of those problems are due to growers switching nutrients in the middle of a grow. You may be able to get a free 500gm sample. All it will cost you is shipping. Check the Greenleaf Nutrients website, and the dot com version of Amazon. Even with the horrendous cost of shipping, this may be your lowest cost option to get designed for cannabis nutrients. That 500gm sample is enough to grow one or two plants to harvest.