Yellow tips at start of flowering.

[itisme]

PICS ADDED BELOW.

The tops of my plants are are yellowing. The have been topped and the tops are yellowing early in flower, just two days into it. The yellow is starting at the base of the leaves and not at the edges. I want to attack this early.

My mix is 9 CU FT of Promix, EWC, Perelite w/ CU FT ratios used below
3/4c -bone
1/2c -blood
2c - kelp meal
1 1/2c Bat guano (high P)
1/4c Diatomaceous Earth
1/2c Soft Rock Phosphate (personally I'd skip this)
1/2c Alfalfa Meal
1/2c Neem Cake
1/2c Crab Meal
1/2c Fish Meal
2/3c Azomite
1 1/3c Dolomite (personally, I'd change this to like 1/3c dolo, 1/3c gypsum, 2/3c oyster shell flower)

 

[kickinit1]

low on nitrogen?

 

[SeaMaiden]

I'd like to see pix, and would need a better idea of the lives these plants have been leading.

 

[itisme]

The room temps are 70-75 degrees F. Humidity is 45-50% range. No bug issues and the soil is as listed. I had great green in the plants until flower and now this. I have only been giving them water.

Pics added. Sorry for poor quality.

 

[Sat X RB]

yes, hard to see detail.

looks like Mg deficiency to me despite the Mg in yr Dolomite. so this is curious and there may be a pH issue here locking out Mg.

to positively identify there is an Mg shortage get a cheapo spray bottle like yr Mum used to use for ironing and fill it with Epsom Salts from the supermarket mixed with water at 1/4 teaspoon per litre. mist the mix on the foliage and you'll see the results within 24 hrs.

got a soil pH test kit?

cheers!

 

[itisme]

Yes that my be it. My dolomite was not crushed but it was all I had and the hydro store only had the same kind. My first time with it. I will do the dolomite, oyster shell, gypsum combo with the next batch. My ph out of tap is like 7.85 so I think that fits the lock out billing. I will try to get better pictures in the am when the sun is out stronger and I can mess with it for a few minutes.

Is there a reason this didn't hit until flowering if that is the issue though? I vegged them a month and a half and they looked great.

Is there a top dressing I can do to it or do I need to watch my ph until next round of soil?

I'll try to find a soil ph kit too.

 

[SeaMaiden]

Super quick fix for Mg- is to use a foliar spray of Epsom salt (aka MgSO4) at the rate of about 1/4tsp/gal water. Be sure to use a surfactant, I use a couple of drops of liquid soap.

 

[Sat X RB]

Is there a reason this didn't hit until flowering if that is the issue though? I vegged them a month and a half and they looked great.

Is there a top dressing I can do to it or do I need to watch my ph until next round of soil?

I'll try to find a soil ph kit too.

may have used up the available Mg, I think. this happens. if the dolomite you added was not granular perhaps yr plants can't access it.

(like D needs soil acidity to become available. in big lumps acidity works on it only gradually. also D contains Ca. if yr D is uneven quality soil acidity may be releasing too much Ca which will actually militate against the uptake of Mg. google "Mulders Chart" and you will see what I mean.)

granular Dolomite sprinkled over the surface of yr soil ... not too much ... just like sugar on top of a cake ... and water in should do the trick for the rest of the grow.

cheers!