White Rhino plants have brown spots

[kasheesh'd]

I was wondering I am growing white rhino, and they are in their 6 week. They have been starting to have brown spots on their leaves and the bottom leaves are turning yellow and then dying. We haven't been fertilizing them since we using micacle potting mix when we first started to grow them? Should we start? Also the fertilizer that we have says to use 1 Tbsp for outdoor and 1/2 teaspoon for indoor? Do we use the outdoor amount since we are using 400w HPS? We have been giving them Mg epsom salts, im thinking it might be a phosphate deficiency also? Let me know thanks. Our plants are in soil.

 

[Mutt]

First I would check the PH. Then I would introduce ferts...the plant may have depleted all the ferts. I would start with the indoor recipe @ 1/2 strength and work your way up to be safe.

 

[kasheesh'd]

here are a few pictures of the spots im talking about

 

[gardenandcats]

Probably nute burn. I would not fert them for the next few weeks.And unless they are MG deficient then they don't need the epsom salt. So no more of that either.

 

[kasheesh'd]

We haven't given them any nutes at all yet so it def. isnt nute burn. Any other ideas?

 

[bombbudpuffa]

Overwatering maybe? How often do you water?

 

[kasheesh'd]

Every 2-3 days.

 

[bombbudpuffa]

Whats the ph of the soil? What kind of soil is it?

 

[kasheesh'd]

Getting a pH tester tomarrow, soil is mg potting soil organic. Going to test pH of water and soil tomarrow and will post results, this reminds me of ChemI lab

 

[bombbudpuffa]

Thats it imo. The MG soil. MG soil is acidic and should have lime or some other ph buffer added to it.

 

[shuggy4105]

yeah i had the same problem with the MG soil, i actually had to transplant out of it and rinse the roots. what you`ve got looks identicle to my previous problem, can also be from a high ph.