Is my plant sick?

Hello all,

I am a first timer poster, and first time grower :D, 5 weeks in I thought my plant was going well, but now it looks as if some of the leaves are 'puffing up' in between the veins, and the leaf tips are curling under. New growth appears to be OK, although leaves are twisting a little.

Grow Info:

Indoor
Soil mix - multipurpose compost with perlite
Fertilizer has an NPK of 4-4.5-8
Soil Ph is 5.5 - 6
Tap water with Ph of 6.8
Watering schedule is maybe once every two days if needed, with a 1/4 strength fert
2 x 20W CFL's 5" from plant
Soil temps are 68F, air temp is around 74F
I have no way of measuring humidity yet.
Lighting is on an 18/6 cycle
Ventilation is provided via an open door in the grow room and a standard oscilating fan!

From the research I have done it looks as if my plant is either suffering from heat stress, salt build up or lack of water. I can pretty much rule out the water aspect, and the heat due to temps, but how do I tell if its really a toxic salt build up? Also I think my soil PH is a little acidic for soil, but my local garden centers dont stock dolomite lime.....are there any other alternatives..maybe homemade?

Thanks in advance for any help

The pH of your soil run-off needs to be 6.5-6.8. Your running too hot, you need to get that soil pH up to at least 6.5. Your currently starting to see the effects of your soil pH being too low.

Not sure if you know the way to get that number dialed in so here is a quick explanation.

First you want to test your tap water, so for this lets say that is 7.5 before adding nutes. Now you want to run some water thru your medium and catch some of the water as it runs out. Testing that will tell you where your soil pH is. Adjust the water that has NOT been added to the medium to get the medium pH where you want it. Run that water thru, when your run-off water is at the right pH then you can add nutes to your water and then water your plants with the nute water. You should see an improvement within 24 hours if done correctly.

Secondly, dont feed your plants nutes yet, you shouldnt use nutes until the plant tells you or you have seen about the 5th internode (thats how i judge anyways) and then start with 1/4 strength nutes.

Hope that helps.

hey whatsthatsmell :thumbsup:, thanks for the quick reply.

I wasn't aware of that technique, so I will give it a whirl and see how we get on.

Glad to help, another thing i was looking at is that it seems that your plant is in a small plastic cup or something like that, you want to plant that into a larger pot or you will start to see signs of being rootbound. When you transplant, make sure that you leave some of the original plant mold(best way i can describe the dirt that the plant is currently in) about 1 inch above the new medium the plant is going in. You want to get that plant up high so you can get the air circulation around the stem of the plant, this will help prevent stem rot and will help with the vig growth your looking for.

I just checked my soil run off and sure enough its running at 5.3, I will definately have to get this sorted. :(

The plant is actually potted in a 25cm deep pot, it was in a 10cm deep until the fourth node, then I transplanted to the bigger pot which she seemed to cope with OK.

Thanks for the info.

glad that i could help ya find that problem quickly, something like that if gone on long enough can be a bitch to get out of.

You're stem looks a little scrawny. Id suggest getting a fan blowing on your plant if possible. Dont need anything big, a cannabilized computer fan would do the trick, basically getting any kinda a "breeze" on your plant will tell it to develop a sturdier stem. Also it looks kinda like its stretching (sativa plants like to grow up rather then out). Try and get those CFLs in a bit closer to your plant if you can, that will encourage it to stop stretching so much and grow bushier.

add anothe cuple lights as well now or within the next 2 weeks

Hi guys,

thanks for all the extra info. My grow lights arrived yesterday (125W Envirolite 6400K and 2700K), and the 6400k has been installed, so that should help a bit.

I also managed to source some dolomite lime, so have added that to the soil and watered it to try and reduce the acidity, they are beginning to look a little better now.

The seed was from a bag of 'Thai' so we'll see how she grows. :smokin:

It looks stretched but healthy, more air flow, don't overwater, and I'm GLAD you got more lights, that's what it REALLY needs the most.

Cool, but how much airflow are we talking? my current fan gently moves the leaves but nothing too vigorous, should I be giving them a good blowing ;)

Naw, if the leaves move at all that is plenty.

Ok cool, thanks, I'll keep it as it is.

Since putting the new lights in, the plant has perked up and bit and growing significantly better.

Just out of interest, when the plant reaches its 5th/6th node should the stem continue straight up and the nodal leaves grow at 90degrees to the stem? at the 6th node my stem seems to grow left, then the next node grows our right as if the stem is splitting....(picture attached due to shoddy explanation)

is this normal......Am i just being a paranoid newbie?:D

To me that looks normal, just the way they grow. As long as you have sufficient light they will continue to grow up tall and nodes just form that way. It's a good thing.

What you just saw is the change from opposite to alternate node placement telling you that the plant is becoming sexually mature.