Hey everybody!
Today's update will be a little tutorial on feeding with Megacrop(MC) and will focus on the signs of what to look for when your plant is hungry.
MC has been formulated with N as a main indicator of when to feed. More N increases the greeness of the plant and the lack of N produces yellow leaves down low.
When a grower is able to detect the changes in colors from the lower part of the plant compared to the upper part of the plant then they are able to read the plants correctly. If a plant is showing signs of a deficiency the very first indicators will be from the lower leaves losing their greeness along with signs of early Mg def. Eventually the leaf will turn a bright yellow if no N is introduced quickly. The damaged leaves will die off regardless but if you notice it sooner than later the leaves will take longer to die off.
The below pic is current from my Lemon AK which I'm having a hard time staying on top of. She's a hungry heffer but I have not been at full dose of MC either. Today she was bumped up to 5.5g with some Calmag and Sweet Candy to try and get some more food into her.
You can also see the signs of Mg def just to the left of the main yellow leaf in the pic. Another closer shot of signs of Mg def is below.
My DDA is going the same route as the Lemon AK if I don't address it soon, which I will tonight. If you look at the lower leaves you can see they are losing their greeness compared to the upper leaves. If this plant was as hungry as the LAK then she probably would be showing signs of yellowing at this stage too. Neither of these plants are showing signs of any other def, including Ca or K.
If I was having a Ca def from a lack of food then I would see those yellow leaves first. They may not be that yellow and only losing their greeness but there would be signs. A Ca def will never present itself on the lowest leaves first so that's another indicator when diagnosing plant issues.
When a plant is being fed the correct amounts of MC then there will be a noticeable green difference. Every chemovar and phenotype will behave differently in coloring so you need to adjust to the plant's colors when healthy and not it's neighbor in the pot next door. Take a look at the Gorilla Glue below who is in the same tent. I like to try and feed the plants the same amount as it makes it easy. In this case it didn't work and I've been struggling, but more often than not they will handle the same feed amount from plant to plant.
So what if I have a def that is not N related such as K def? Well there's two main possibilities. First is overfeeding and second is incorrect pH levels in the media.
When using a buffered medium such as FFOF, MGOS, or Promix there is no need to pH your nute solution. This applies to all nutes and not just MC. Growers will pH their nutes for reassurance but to continually pH your nutes at 6.5 does not make your media 6.5.
MC has a calculator that for the most part is pretty good. The problem is determining the stage of growth your plant is in. I find many times a grower thinks they are in late veg and really they are still in the small plant or normal veg stage of growth. So by overfeeding MC we risk the chance of lockout of certain nutes. When I see a K def during veg stage that's a sign to me that the problem is overfeeding or media issues and not a sign to pump up the nutes.
Many times a simple reset of the media and coming back at a lower dose right away will tell you if overfeeding was the issue. If it wasn't then I would check the pH in my media through a slurry test to make sure it was OK.
So if you don't see any coloring loss on the lowest leaves then look at something else as being the problem. Hopefully with some of the above info you can get ahead of any problems instead of chasing them.
