yellow spots on leaves?

Just in the last couple of days these little yellow spots have started to appear on the very top leaves of my plant. Its about 60 days old and this has just begun. I just recently started using pureblend pro flower, so i wonder if the problem is because of my nutes? Room stays at about constant 78F temp and is humid.

Anyone seen this before?

 

'could be spider mites.

 

I think Scholar Warrior is right.
Carefully inspect the leaves, especially the undersides.
Using a magnifying glass is helpful but not neccasary.
Spider mites can devestate a garden in just days.

 

I dont think its spider mites because its only affecting one of two plants growing side by side. The problem HAS gotten worse, though. This sucks because I know I'm slowly watching my plant get sicker and I have no idea what to do. I've stopped feeding it nutes and even stopped watering for a few days because I think I might have overwatered it a little. The tips of the topmost leaves are beginning to look burned and the curling and drooping is getting worse all around.

 

Doesnt look to me like a pest prob but a Mg deficiency.You stated upper leaf tips are burnt,do ya mean new growth.Mg deficiencies show with either yellow,red,orange,purple,rust,or dead spots with some upward curling.Upper leaves contain fixed nutrients,meaning they stay put within the cell structure.These include S,Ca,Fe,,Mn,B,and Cu.Causes of Mg deficiencies vary.Poor soil or soil with drainage probs can cause it as well as excessive amounts of Ca or K.With a Mg deficiency you can correct with 2 means,if your Ca levels are normal use sulfate of potash-magnesia or if Ca/K levels are high mix 1 tbl spoon of epsom salts per gallon of water.You may have alkaline soil as well,this could lock out many different nutrient.A good soil test kit is whats needed,they run $50 and up.

 

Thanks for the reply, meangreen. I was really hoping someone like you or tyedye or one of the other resident know-it-alls (i mean that in a good way!) would reply to the post.

I think the nutrient deficiency is definately what is going on here. The leaves curl downward, though, not up. And yes, the burnt tips are showing on the new growth, not the older, established fan leaves or whatever they are called.

At this point, however, I'm only about a week away from harvesting so I dont think I am goin to do much about the problem except chalk it up to beginner problems and lack of knowledge about what I'm doing.

What perplexes me, though, is that this problem has only happened to one of two plants that I'm growing. The other plant, a different strain, is doing okay. Its buds are not quite as full, but it shows none of the problems that the other is. Do different strains react differently to growing conditions?

Also, these problems did not start showing up until I started giving it Pureblend Pro 2.5-2-5 formula and switched back to using tapwater instead of the brita filtered water. I'm sure the tapwater has something to do with it, but do you think the nutes was the problem too?

 

Chances are it was not your ferts but the tap water as depending on where ya live is generally very alkaline and that will cause a raise in soil ph and if the tap water has a high enough alkalinity can raise the soils ph enough to begin locking out some nutes.

 

yup, I think meangreen is prolly right on the money. I think a PH meter or a good test kit is the first "tool of the trade" any beginning horticulturist should invest in. There is a direct corelation between PH and nutrient uptake.
I don't have any experience with "Pur-blend" products, but have found that some nutes will throw the ph off. Dolomite lime added to the soil mix before planting acts as a "buffer" for ph.