please help

[killian123]

Hi all, second year outdoor grower here. I need a little help diagnosing these plants please.
The yellowing started around three weeks ago and the edge and tip about a week ago.
plants are four months old and were doing great up until 3 weeks ago.

I built a temp green house around them as the weather in my area in canada fluctuates from desert to monsoon conditions. I only feed them around three times during veg as they were growing like crazy and now im wondering if its a lack of nute problem, bug, or water issue. i have searched the web long and hard to find pics of leaves similar to mine but havnt come up with anything.
Any help would be greatly appreciated

 

[SSHZ]

My initial guess would be over-fertilization based on the burnt leaf tips........what and how much you feeding them?

 

[hotrodharley]

Looks like magnesium deficiency and calcium deficiency both.

 

[killian123]

thanks for the quick reply. only fed them 3 to four times during the last 3 1/2 months. Was using general organics, biothrive grow. The strange thing is that i have not fed them anything for around 4 weeks. They started to take over my small shitty greenhouse. 2 are starting to flower and i was going to feed them but i thought i should ask on here before

 

[killian123]

Ok, dont have any cal mag at home but i will buy some at the shop. If it is a cal or mag deficiency, how long will they bounce back after i treat?

 

[hotrodharley]

thanks for the quick reply. only fed them 3 to four times during the last 3 1/2 months. Was using general organics, biothrive grow. The strange thing is that i have not fed them anything for around 4 weeks. They started to take over my small shitty greenhouse. 2 are starting to flower and i was going to feed them but i thought i should ask on here before

Common for these both to show up early to mid flower.

 

[hotrodharley]

Ok, dont have any cal mag at home but i will buy some at the shop. If it is a cal or mag deficiency, how long will they bounce back after i treat?

The leaves won’t repair. Watch for new damage to make sure you’ve covered it. Usually a teaspoon per gallon is sufficient. Especially if using tap water.

 

[killian123]

Ok, thanks Hot rod. I have a bottle coming. i need to leave for work tomorrow and was wondering if i could give them a dose of cal mag as well as flowering nutes? Or maybe one thing at a time? never had to use Cal mag before. dont know if it interacts with fert?

 

[Hailey's Comet]

Could be PH issue or root lock/bound you don't say how big your pot is but you said plants are 4 months old.

 

[killian123]

@haily. i thought this may bite me in the ass.... they are in 50 litre pots. did them from seed this year , not clones and should have planted them in bigger pots but i didnt expect them to grow this big and this fast. All four are over 6 ft and i dont know what to do in regards to possibly transplanting?? last week the started showing roots from surface soil. covered them up.
any suggestions?
Should i even attempt a transplant this late?

 

[killian123]

ph tester is on its way.. i know my well water is high in calcium. ill know this evening

 

[Hailey's Comet]

@haily. i thought this may bite me in the ass.... they are in 50 litre pots. did them from seed this year , not clones and should have planted them in bigger pots but i didnt expect them to grow this big and this fast. All four are over 6 ft and i dont know what to do in regards to possibly transplanting?? last week the started showing roots from surface soil. covered them up.
any suggestions?
Should i even attempt a transplant this late?

If the roots are coming out the top it may be a problem. Transplanting ir outside to the ground is feasible otherwise I suggest you check out how to root prune and verify it works. From what I have seen they just do some root maintenance/cutting and replant.

 

[killian123]

Thanks again, I'll have to make a decision on that, just tested my well water and its above 7 on the scale so I'll get some ph down...really freaked out bout transplanting these plants..lesson learned I guess

 

[Hailey's Comet]

I could be totally wrong but it kind of happens to me like this. Then the stems went dark purple and the nodes became aggressive and short no fan leaves.