Upper leaves discoloration/dying leaves

[lazarus]

Hi

I'm 5+ weeks into flowering of a autoflower that flowers for aprox 8 weeks and the last few days the top leaves of my plant has started looking as below

In case it is light/heat problems i have moved the lamps a little up, but don't think that the problem since it has not been getting taller for a while. Should i just flush and hope for the best? Could it be missing photasium? I've started with extra but only half stength as with the rest of my fertilizer program as full strength of my other fert tends to burn plants. Lower leaves looks healthy and green altough maybe a bit to dark green? The leaves also feel a bit crispy but i let the plant dry out quite a bit between water so could be why.

I've also noticed some of my outer leaves has a bit of a "claw" at the end.

 

[iwltfum]

That looks like your nutrients are too strong. You could try flushing or just using plain water for one or two waterings and then bring the nutes back up very slowly. Is it in organics or hydroponics?

 

[NuttyProfessor]

looks like pest damage also , check under leaves

 

[lazarus]

Yeah, someone else also suggested it being trips, but as far as i can tell there's no signs of any bugs that i can see. But wil keep an eye out and have also hung some yellow glue-squares up just in case. The underside of the leaves looks healthy.

I have flushed and hope that helps. Sunday i should be about 2 weeks of from harvest so will have to start flushing/using clean water anyways.
It is a soil grow and i use a Hesi Starter Kit for Soil as nutes. If it is nute burn it must be from the extra phosperuous (or buildup in the soil) as that's the only change i have made recently. The damage happeded very quickly but have spread a little bit since then (hopefully flush will stop it from getting worse). Just hope my main cola (or the rest for that matter) is not going to be killed this close to harvest.

 

[NuttyProfessor]

good luck with her

 

[iwltfum]

Yeah, someone else also suggested it being trips, but as far as i can tell there's no signs of any bugs that i can see. But wil keep an eye out and have also hung some yellow glue-squares up just in case. The underside of the leaves looks healthy.

Thrips and spider might damage look very similar. It might be a good idea to check for mites. The dots definitely raised my suspicions about bugs also.

 

[lazarus]

I've kind of conveniced myself that the problem is due to heat after all because i noticed the temps have been getting above 30 celcius (31-32) and my levaes could look a bit like this guys who also runs a high temp: Hi need some help to diagnose my plant

Flushing haven't helped and have still not seen any pests at all, so i think i'm going to harvest tomorrow so i don't loose the plant (more and more leaves turn brown). The trichomes are not amber yet, but they are all milky white so hope i can still get some good smoke out of it. What do you guys think?