Orange marks on leaf

[JohnyT]

View attachment 100715

Hi there, got some funky orange goin on on a couple of my plants, what could it be?

 

[JM]

have any other info?

looks like beginning of potassium deficiency

https://www.autoflower.org/f7/self-diagnose-your-plants-basic-deficiencies-list-11.html

 

[JohnyT]

Well They are growing in bio bizz soil and have only been fed once so far, the feed was a bit early but that was several weeks ago and have not fed them since. I have been watering with rain water collected out of the water butt.
They are currently growing under 700w of CFL temps are between 19 and 24c depening on time of day.
The plants are x3 Speed Devil and x3 Pineapple express autos, that picture came from one of the pineapple express's

 

[namvet25]

Some of those spots look a little eratic,just for the hellof it check your plants for insects just to eliminate that problem.

 

[Hugo]

There's a number of things that would influence the diagnosis.

Do you keep track of pH in feeding and in run-off? If so what are the levels you're registering. In what part of the plant did this spots appear? On the bottom of the plant (old growth) or on the top (in new growth)? How old is she by now? How's the rest of the plant?

Cheers

 

[JohnyT]

Well Its near the top and is on a few of the leaves. I just went out and bought a PH meter just now and its Reading 5.8!! so I guess thats what my problem is. I guess I need some PH balancing stuff ASAP. Whats the best way forward on that?

 

[archaiclife]

Id say use some dolimite lime slow release and start phing ur water with ph up so that ur runoff comes out at 6.5. Make sure the ph up u buy is safe for use wit organics.always test ur runoff now that u got a meter it will help u so much.

 

[JohnyT]

Cool thankyou for the info. I know it's probably hard for you guys to tell but with 10 litres of soil at ph 5.8 what should I ph the water to counter balance this? Just a rough idea would be cool cos I really have no idea. Mathmatically I would have said 8.2 but that's probably wrong.

 

[archaiclife]

7.0 - 7.3 with your water should get u were u need to be. Make sure ur next watering u get alot of runoff then let it dry and do it again and check the runoff ph. It would probably help to have some lime on the soil to help homd the ph till it straintens out just keep checkin ph of ur runoff. With ur water always split the diference i. Ur soil ph and water ph to she where how much higher or lower to ph ot for the next time. U want a ph of 6.3 - 6.7 idealy

 

[JohnyT]

Cool thanks again. I've got a much better idea of what to aim for a d how to go about it.