Cracking and Discolouring Lower Leaves, Easy Ryder, Day 26, 400W

Hi all!

So I'm carrying out an Easy Ryder, 400W HPS, 6 Plant, tent grow and have come across a problem with my plants that I was hoping you could diagnose. Here's my journal for the full story.

I've already made a post about it there and this is going to be mostly a copy and paste of that post to get some information from a more relevant part of the site. I hope that's ok. Here it is:

The malody seems to be affecting the lower, older leaves, particularly of "Plant 2" (see Journal), and to a lesser extent, "Plant 1". I was hoping someone could tell me if there is cause for concern and if so what I am doing wrong and what can be done to remedy the situation.

To describe it in words, a couple of the lower leaves seem to have lost that intense green colouration and have begun to crack and develop patches of a brownish colour. These patches look a bit as if some impure water had been spilt on them and then dried to leave a residue on the leaf. I am not actually concerned about the purity of my water but I suspected that maybe a bit of water had been spilt on the leaves during watering and damaged them somehow? Is there any sense to this? Did I miss some rule about keeping the water off your leaves?

Or maybe that's just what happens to old leaves? I've heard it's good to trim the bottom third of your plant so maybe it's time to do that? Or any other suggestions you'd have I'd really appreciate. Here's the problem in pictures:

Plant 2 - 26 days from beginning germination in soil:





Thanks for your input.

looks like they are drying out or may have nutrients splash on them

Sorry, should have mentioned that I'm not using any nutes yet. Another plant (plant 1 in my grow journal) is beginning to show stronger symptoms too. The leaves have a couple of dry blotches like above but fewer and droopy yellowing leaves. I thought that it could be a Nitrogen deficiency as I've read that this can cause droopy yellow lower leaves (fan leaves). Does that sound likely for a 26 day old (from the start of germination) plant?

I'd be surprised if I was under-watering it, but it could be the problem I guess. I will give plant 1 a good watering, what do you guys think about giving them their first taste of nutes?

Thanks for the attention George. And for the grilling machine in my kitchen.

Also, I have splashed water on them. Could that be the cause of the blotches & cracks with the yellowing and drooping being attributed to something else (like a deficiency)?

Ok so to follow up, plant 2 (orignally the worst plant) is not looking any worse really. Plant 1 on the other hand is really starting to look bad. It's not as blotchy as Plant 1 but very discoloured, yellow and droopy. Some of the leaves at the very bottom have began to curl up and lets face it - die!

Plant 1:





Plant 2:



Please help experts!

Rapidon said:

Ok so to follow up, plant 2 (orignally the worst plant) is not looking any worse really. Plant 1 on the other hand is really starting to look bad. It's not as blotchy as Plant 1 but very discoloured, yellow and droopy. Some of the leaves at the very bottom have began to curl up and lets face it - die!

Plant 1:

Plant 2:



Please help experts!

Click to expand...

How much water and what's the temperature?

Temperatures are quite variable between lights on and off which could be a problem. Something like 30°C (85°F) at it's height and goes down to about 15°C (60°F) at night. By the way, when I measure temperature where should I put my thermometer? I heard 85°F is ok but such a big range isn't a good thing. Is that correct? I should have a new fan on the way but I think the ebay seller is fucking me around.

[FONT=arial, sans-serif]I'm watering them every couple of days when the pot feels lighter and the soil feels and looks dry. Maybe 2 litres at a time...

I just gave them some nutes for the first time last week. Miracle Gro All-Purpose... I know, I know, lots of people hate it. I just used about 2 litres at a little under half strength between the 3 oldest plants.

Cheers.[/FONT]

So to follow up this thread here are some more pictures showing the problem. Maybe it will help someone else.

Plant 1 - Easy Ryder - 36 days from germination:











Plant 3 - As above:




I have since nuted them up with more Miracle Gro Soluable All-Purpose Plant Feed (high nitrogen content) as well as some Bio Bloom (low nitrogen organic liquid feed for flowering) and the the problem seems to have stopped. Old yellowed leaves have not recovered but other leaves don't seem to be turning, or at least not nearly as fast. I also have some younger plants that are the same type and in the same soil / other conditions and they are not showing symptoms.

I therefore conclude that it was most likely a nitrogen deficiency. I've also recently realised that my soil is crap and this is probably what brought on the deficiency so early.

As I stated in my Grow Journal...

DO NOT USE LEVINGTON MULTI PURPOSE COMPOST!!!

Just look at the Amazon Reviews, I wish I did! I also have lots of soil bugs and weeds (not just the good weed)!

Plants use potassium in stomata regulation and respiration. Seems like from what I read they are under nuted, specifically in potassium, magnesium, and calcium. Calcium is also a growth regulator, and that plant needs lots of it to signal roots to grow and carbohydrates to transport. Also what you have going on is shaded leaves tend to die off anyway, since your plants are droopy due to too much water loss, its shading the leaves and the plant is sending hormonal signals telling it to use up the good nutes in the lower leaves since they are light deprived anyway. re-introduce them gradually, don't shock them. Back off on the light for a couple of days, raise humidity if you can, and start a gradual feed program high in potassium, calcium, magnesium in about a 4:2:1 ratio. Hope that helps good luck.