Yellow leaves/Brown Spots......help please

Hey all,

One of my 6 girls (33 days flowering) has some problems. This one has always been a bit different to the others! All other girls are doing just fine, they are all the same strain, same feeding schedule etc.

Check out the attached pics.

I am suspecting an Mg deficiency, but possible other problems too.

I have been feeding with BioBizz organic nutes through the entire grow. Currently they are getting 2ml of BioGrow and 2ml of BioBloom per litre, once a week. I have also fed light doses of micro nutrients/bloom stimulator (Alg-a-mic and Top Max).

Fluids are always PH'd to 6.8

Any thoughts as to what my plant is crying out for here??? Any help much appreciated. Thanks.

Nobody??

Oh well, probably not much I can do now anyway. Only got a couple more weeks left, so hopefully she'll struggle through till harvest.

I would possibly say a nitrogen def. its normal towards the end of flowering....
also.... make sure you are getting a magnifying glass for harvent time..... dont want to pull em too early!!!

about your def. wait on a couple of more replies.... or maybe even send Mogie a pm about your issue... if shes not grumpy, she will defintately help out w/ your issue... (shes the deficiency goddess.)

SnowWhite said:

HAny thoughts as to what my plant is crying out for here??? Any help much appreciated.

Click to expand...

I still can't decide on this one SW.

I had a similar situation to this in my last grow and it baffled me then as well. Two clones, identical in every way except one was a triofliate (whorled phyllotaxy) they were fed the same, potted in the same soil mix in the same pots watered the same with the same water and nutrients and they were exactly the same size - one showed more serious Mg deficiency than the other! I knew it was Mg because I'd had the same problem on the Sensi Star I grew from seed in the previous frow. I'd been feeding them epsom salts in irrigation water as a preventative measure, yet one came out with the yellow leaves and the other hardly had any signs of it at all, although there were some signs.

The one leaf picture shows classic signs of Mg deficiciency, although the ones still on the plant could also be Nitrgoen deficient as just under 5 weeks is a classic time for N deficiency to show. Even if it is N deficicency, I think you're better off simply not trying to correct it at this stage in flowering as it sounds like they only have about another 3 or 4 weeks to go and you'll need to start lowering your feed levels in a couple of weeks anyway. Also, you don't want to be giving the plant raised levels of Nitrogen at this stage in flowering and you can't use any foliar sprays for risk of bud mould.

So lets assume it's Mg, as treating it for Mg won't harm the plant in anyway in terms of toxicity at least not in terms of a couple of doses. You need to bear in mind that epsom salts still contributes to the TDS content of your irrigation/nutrient feed so lower the doses of Bloom and Grow slightly to compensate for the higher salts. Without an EC meter it's hard to calculate the correct nutrient feed EC.

Also at about two weeks from harvest you need to stop feeding 'bud and health' booster products like Topmax and Bioheaven and simply feed slightly reduced quantities of bloom and grow with grow being fed double the amount of bloom. This isn't to boost the N levels, as the smaller amounts being fed at this time contains lowered Nitrogen levels, but to feed the carbohydrates and sugars in grow (similar in a way to Molasses as they're both derived from Sugar beet refinery by products) to stimulate the micro-herd and to help increase the plants metabolism with the sugars.

Cheers babygro, great advice as usual. I've not got any Epsom Salts so I'll try and get hold of some to supplement the Mg a bit and I'll def be using them in my next grow, whatever that may be. I do like the look/sound of those mandala seeds you're using on your current grow. Very, very good value and they sound the business. I like the fact they are tolerant of high temperatures, that's a good trait for me. On HOT days, my grow room goes over 30 (unless I prop the door open a bit) and it sounds like the mandala strains would not care about this. But I plan to improve ventilation for my next grow as well.