Why are my leaf tips going yellow?

[oscli]

hi

some of my plants, 3 weeks into flowering, are going yellow at the tips, generally at the top of the plant and im wondering why.

can anyone help please?

[The Cannarchist]

Can you get me a close up of an individual leaf tip Oscli

Is the yellowing on the vein or between the viens on the leaves?

[The Cannarchist]

And what are you feeding them with?Grow style?

As much info as you can give will help

[oscli]

hi

heres a few more pics...

they are being fed canna terra flores and are in soil. they are on day 24 flowering and have been fed twice with canna flores at 3/4 strength and a couple of times canna vega at 1/2 strength.

thanks

[The Cannarchist]

Get you hand into the pot and pull out a handfull of the soil.Add to it an equal amount of Ph balanced (7) distilled water.Let it sit for an hour then strain off the dirt.

Do a Ph and PPM test on the resulting liquid and tell me what it is.

I'm leaning to a phosphorous def at the moment ,but only a mild case.

[nuggdigger]

Good answers.
If your stems are soft i would suspect over fertilization, especially N. Also i suspect there could be an over watering factor by looking at your media, what is your media ratio anyways?..i don't see much perlite floated to the top of the pot. Over watering could lead to damaged roots or insufficient soil aeration. There is also the possibility this could be related to not enuff of one of the macro nutrients, giving the blanched out effect.

Cannarchist method of digging out a handful of media to measure is a bang on idea i can relate to as i used it in environmental services. Of course we had a co2 press to speed up the draining process so we could test onsite, and a few other nifty testers not normally used, the process is sound. First off you are able to examine you media before you do anything at all..for abnormalitites..salt accumulation, water volume, density, porosity, etc. Then by using distilled water you are ending up with a solution that was in the soil, in measurable suspension, nothing added to it. From there its easy to test and establish the rate of EC and pH in your media. Another location to test where your media is at is in the runoff pot. Hope it works for you. incidentally we used the press method to make solution to test for EC, pH, nitrates, sulfates, hydrocarbons, calcium, magnesium, phosphates,sodium, potassium, iron, and a few other bizarre items. His method is good way to go:tup:

peace:pipe: