Is this a Calcium or Phosphorus deficiency?

[BelliPier]

Hey guys,

This is my first grow and it's been 53 days since the germination out of the soil.

There are some bronze/rusty spots in lower-mid leaves. I added some CalMag Extra a week ago but I dont really know if it helped. I've attached pictures of the problem. Also worth mentioning lowest fan leaves turned yellow-brown and died but I dont have pictures of them.

1) What could be the issue?
2) Do the plants look okay for their age, in regards of size? (internodal spacing is very tight compared to other plants I see online, very bushy) I have topped the plants 1 time and done some LST, each canopy is almost even with 5-6 tops. Im thinking of switching to flowering in 10 days. Or should I wait a little bit more for it to get bigger?

Some info:
Soil: Biobizz Light Mix - 3 gal. pots.
Nutrition: Biobizz Grow at full dosage, every watering. Sensi CalMag Xtra, just used 2 times.
Light: 450w MH at 50cm distance.
Temperature and RH are stable.

Thanks a lot!

 

[BelliPier]

I took some other pictures of yellowing - dying leaves from the other plant. This one does not have rust spots but has these yellowing leaves. Any help is appreciated. These leaves are not the lowest leaves btw. There are healthy and green leaves below these ones, thats what seemed weird to me :/

 

[Aussieaceae]

At a hunch i'd say give some plain water, once or twice. Then cut the nutrient back a bit. Full dose of nutrient every watering doesn't sound good to me.
If it keeps it up afterward, I'd maybe consider something more nitrogenous fert wise.
Maybe a little dolomite lime too, hard to say for sure. Biobizz light mix seems to be advertised as a soil like medium. I don't believe calmag would be as good as lime. You want something slow release.
I haven't used Biobizz products before, but it's what i'm goung to assume, based on the description and pics.

How frequently are you watering and are you watering until runoff?

 

[BelliPier]

At a hunch i'd say give some plain water, once or twice. Then cut the nutrient back a bit. Full dose of nutrient every watering doesn't sound good to me.
If it keeps it up afterward, I'd maybe consider something more nitrogenous fert wise.
Maybe a little dolomite lime too, hard to say for sure. Biobizz light mix seems to be advertised as a soil like medium. I don't believe calmag would be as good as lime. You want something slow release.
I haven't used Biobizz products before, but it's what i'm goung to assume, based on the description and pics.

How frequently are you watering and are you watering until runoff?

Thanks for the suggestions. Biobizz Light Mix is advertised as a very light soil, as in it doesn't have many nutes and I have read many topics about this soil and nutrient deficiencies, that's why I slowly increased my feeding to full dosage. Do you think it could be nutrient burn instead of a deficiency? I water every 3-4 days depending on the soil's condition (based on weight check and dryness of the top layer) and I water till I see %5-15 runoff. I think I was giving them really low amounts of water (500ml per plant) till now but I increased it to 1L per plant in the last 1-2 weeks and they mostly seemed to like it

 

[.Smoke]

This always helps me with diagnoses. Hope you get it figured out.

 

[Aussieaceae]

Thanks for the suggestions. Biobizz Light Mix is advertised as a very light soil, as in it doesn't have many nutes and I have read many topics about this soil and nutrient deficiencies, that's why I slowly increased my feeding to full dosage. Do you think it could be nutrient burn instead of a deficiency? I water every 3-4 days depending on the soil's condition (based on weight check and dryness of the top layer) and I water till I see %5-15 runoff. I think I was giving them really low amounts of water (500ml per plant) till now but I increased it to 1L per plant in the last 1-2 weeks and they mostly seemed to like it

Every 3-4 days sounds pretty good to me and would seem it's holding water pretty well. It's a decent pot size for the size the plants are, i'd just be wary with nutrient every watering., because that water is holding nutrient as well. That generally isn't a good idea unless running hyro.
I'm not suggesting it's nutrient burn, but possibly a lockout or deficiency caused by an abundance of something else. That's why i'm suggesting plain water once with good runoff, before giving nutrient again.

I searched out Biobizz grow online and the NPK seems to be 4-3-6?
I find for my own soil, it's usually better if the N / K is closer to even and the P just a tiny bit less. It's best ime to have something balanced during veg, slightly in favour of nitrogen.
I'll be honest 4-3-6 NPK reads more like a ratio for flower to me. Never used the same bottle though, so I can't speak from experience in regards to Biobizz grow itself.

If there aren't any signs of unnatural red / purpling stems and splotchy leaves, I wouldn't immediately assume phosphorus either.

I'd start with plain water one time, then see where it goes from there.
Likely a little dolomite just before giving nutrient the next time too.
Outdoor soil i'd be going straight for blood and bone meal for a bump in N + P. It's more of a slow release as well. I'd be a little concerned it might get a bit funky indoors as a top dressing. But using lightly then covering with soil or mulch and it should be just fine.
You can try just smidgen of Epsom salt when you give plain water too, for a bit of mag. A teaspoon per gallon or two and see if they green up a bit.

Imvho calmag extra likely wouldn't be helping things much at all. You ideally want something slow release and organically based, to support microbial breakdown.
Calmag solution is instantly available to the plants, which could potentially have a lockout effect on other nutrient in your Light Mix.

Sorry mate, all I can really offer for advice. Hope it helps and that you figure out what it is.
Take your time figuring it out, one step at a time. Another week or two before putting to flower should be fine.
Ideally I'd keep them in veg myself, until I've found the cause and the plants are recovering.

All the best and good luck.

 

[BelliPier]

Every 3-4 days sounds pretty good to me and would seem it's holding water pretty well. It's a decent pot size for the size the plants are, i'd just be wary with nutrient every watering., because that water is holding nutrient as well. That generally isn't a good idea unless running hyro.
I'm not suggesting it's nutrient burn, but possibly a lockout or deficiency caused by an abundance of something else. That's why i'm suggesting plain water once with good runoff, before giving nutrient again.

Sorry mate, all I can really offer for advice. Hope it helps and that you figure out what it is.
Take your time figuring it out, one step at a time. Another week or two before putting to flower should be fine.
Ideally I'd keep them in veg myself, until I've found the cause and the plants are recovering.

All the best and good luck.

Thanks a lot for the advice mate. That's all I could ask for! Sadly, I can't access to dolomite where I live, it's not sold in small amounts for retail. I gave very low dosage of grow (quarter dos, just so I didnt immediately cut it) + epsom salt to the plant in question with a good runoff. The NPK ratios and nutrient schedule of Biobizz also makes me scratch my head. Their nutrient schedule suggests using both grow and bloom nutrients during flowering, which seems like a huge N ratio for bloom period, weird. Switching to another brand mid growth could lead to other issues I suppose?

Little brown spots have spread throughout newer-middle growth. Please see the pictures. (You can also see purpling of stems, but I dont know if this is normal or not) Although the plant looks healthyish overall to me, am I right? Rust spots on actively growing areas/newer growth suggest that it's an immobile nutrient deficiency, I cant think of anything else than Calcium based on the charts I saw online. What would be my next step other than using CalMag? (Thats all I have that contains calcium) Thanks again for your reply and suggestions mate!

 

[polishpollack]

That doesn't look like over fert. I suspect something else, like a nutrient is missing, but not sure right now. Usually with over fert, the leaf tips die off. I don't see much of that in pics.

 

[Aussieaceae]

Thanks a lot for the advice mate. That's all I could ask for! Sadly, I can't access to dolomite where I live, it's not sold in small amounts for retail. I gave very low dosage of grow (quarter dos, just so I didnt immediately cut it) + epsom salt to the plant in question with a good runoff. The NPK ratios and nutrient schedule of Biobizz also makes me scratch my head. Their nutrient schedule suggests using both grow and bloom nutrients during flowering, which seems like a huge N ratio for bloom period, weird. Switching to another brand mid growth could lead to other issues I suppose?

Little brown spots have spread throughout newer-middle growth. Please see the pictures. (You can also see purpling of stems, but I dont know if this is normal or not) Although the plant looks healthyish overall to me, am I right? Rust spots on actively growing areas/newer growth suggest that it's an immobile nutrient deficiency, I cant think of anything else than Calcium based on the charts I saw online. What would be my next step other than using CalMag? (Thats all I have that contains calcium) Thanks again for your reply and suggestions mate!

No worries,

I think you're right. Perked up a fair bit and is a tad greener?

Any gypsum or lime in smaller quantity? Gypsum would probably be better because it'll be faster activating and won't effect ph as much. Lime will be fine if you go easy on it, 1 or 2 tbsp or so, then see how they like it. Same with the gypsum, just a spoon or two to start with. You can keep supplementing the Epsom salt from time, to time if it helped too. Just keep the amount the same, less is generally more.

If you're forced to use calmag just take it easy with it. Again less is generally more.

Post the NPK of the bloom, dosages for both too, that'll help a lot.
I'd generally follow the manufacturer's recommendations besides the suggested strengths.
Tbh I think it would benefit from a little nitrogen but focus on the calcium and magnesium first.
Bare in mind your calmag extra is probably 4-0-0 or so as well.Use it very sparingly.

Happy to help, no problem at all.
Good luck, please keep updating.

 

[SheeshM]

I didn't notice any mention of ph. Make sure you're ph is in range so that the plants can take up the nutrients.

 

[BelliPier]

No worries,

I think you're right. Perked up a fair bit and is a tad greener?

Any gypsum or lime in smaller quantity? Gypsum would probably be better because it'll be faster activating and won't effect ph as much. Lime will be fine if you go easy on it, 1 or 2 tbsp or so, then see how they like it. Same with the gypsum, just a spoon or two to start with. You can keep supplementing the Epsom salt from time, to time if it helped too. Just keep the amount the same, less is generally more.

If you're forced to use calmag just take it easy with it. Again less is generally more.

Post the NPK of the bloom, dosages for both too, that'll help a lot.
I'd generally follow the manufacturer's recommendations besides the suggested strengths.
Tbh I think it would benefit from a little nitrogen but focus on the calcium and magnesium first.
Bare in mind your calmag extra is probably 4-0-0 or so as well.Use it very sparingly.

Happy to help, no problem at all.
Good luck, please keep updating.

Grow is 4-3-6 and Bloom is 2-7-4. And Calmag Extra is 4-0-0 as you said. I will stick with calmag for time being but will try to find the alternatives you provided asap and use it sparingly. Btw I saw some people suggest start adding Bloom nut. when the preflowers show themselves and saw other people suggesting start using bloom only after the flowering stretch is done, which one is more accurate? I will keep updating! Thanks a million bro!

Make sure you're ph is in range so that the plants

I use bottled spring water with 7.0-7.2 ph. Biobizz says this is a perfect ph for using with their nutes and soil will buffer it down to 6.2 as needed. I do not have a PH control pen but I have some paper tests and when I test the runoff water with them, result color is around 6 PH so I assume all is well regarding PH?

 

[Aussieaceae]

Grow is 4-3-6 and Bloom is 2-7-4. And Calmag Extra is 4-0-0 as you said. I will stick with calmag for time being but will try to find the alternatives you provided asap and use it sparingly. Btw I saw some people suggest start adding Bloom nut. when the preflowers show themselves and saw other people suggesting start using bloom only after the flowering stretch is done, which one is more accurate? I will keep updating! Thanks a million bro!


I use bottled spring water with 7.0-7.2 ph. Biobizz says this is a perfect ph for using with their nutes and soil will buffer it down to 6.2 as needed. I do not have a PH control pen but I have some paper tests and when I test the runoff water with them, result color is around 6 PH so I assume all is well regarding PH?

I like nitrogen in stretch myself. I'd say once you find what's working in veg to stick with it for the first few weeks of bloom, then go with the flower ratio the manufacturer recommends. Right around the time when stretch is slowing down and the buds are setting. If it's gonna be a 6-10-10 or there abouts, it sounds alright to me.
I wouldn't ph the water myself either, imho Biobizz is right when they say not to worry. But I wouldn't personally use the runoff as an accurate measurement for ph.
If you need a more accurate measurement use slurry kits from a hardware. You make a slurry with the liquid and soil, add the powder to the top and wait. They're surprisingly accurate and affordable.

Do get the gypsum or lime if it's available. Having slow release calcium in the soil really helps, especially when supplementing fertz as well.
I don't believe ph is to blame myself. I think you just gave them a little too much love and over fert'd. This can potentially cause a drop in soil ph, but imo from what you say it's probably ok. If you do end up getting some lime it'll help buffer the soil and help prevent this from potentially occuring.

Just go easy on everything as you already know.
Plain spring water at ph7 with no nutes, every few waterings really isn't a bad thing and your plants will generally thank you for it.
Try a half dose of your nutes next watering imo with only a tiny bit of calmag. Way, way less than the recommendation.

Keep things minimal and steady. As long as you're seeing improvement, don't change it.
Then once they're back on track you can start increasing in tiny amounts, until you hit the sweet spot. Plain water every once in a while and it should be sweet.

Not a problem, good luck and thanks I'll keep a lookout for your update.

 

[Moonmanyyc]

Thanks a lot for the advice mate. That's all I could ask for! Sadly, I can't access to dolomite where I live, it's not sold in small amounts for retail. I gave very low dosage of grow (quarter dos, just so I didnt immediately cut it) + epsom salt to the plant in question with a good runoff. The NPK ratios and nutrient schedule of Biobizz also makes me scratch my head. Their nutrient schedule suggests using both grow and bloom nutrients during flowering, which seems like a huge N ratio for bloom period, weird. Switching to another brand mid growth could lead to other issues I suppose?

Little brown spots have spread throughout newer-middle growth. Please see the pictures. (You can also see purpling of stems, but I dont know if this is normal or not) Although the plant looks healthyish overall to me, am I right? Rust spots on actively growing areas/newer growth suggest that it's an immobile nutrient deficiency, I cant think of anything else than Calcium based on the charts I saw online. What would be my next step other than using CalMag? (Thats all I have that contains calcium) Thanks again for your reply and suggestions mate!

 

[Moonmanyyc]

IMHO I would check PH and PPM of your runoff ever time you water sounds like a lockout to me and looks similar to lockout..........try just phd water kinda flush and check runoff.......good luck