Need Info on Pro-mix BX

Hi guys
I just started out awhile back using Pro-Mix BX and things havent been 100% great.
The plants arent as robust as they should be.
Does BX have calcium or lime added?
Also, i havent been adding anything and i read on here that you should to add like 20% perlite?? I would say the not added perlite is why my soil stays too wet.
Worm castings should be added @ what 15-20%??
Thank you guys for any information. Its greatly appreciated.

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@Myfriendis410 will know more than I will about this.
If it’s anything like coco, you’ll need calmag.

Thank you @Covertgrower

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This?

Peat doesn’t sequester calcium like coco does and is run at a higher PH as well. I run Promix HP at 6.0 and use no added perlite or any other additives.

What are you trying to do? If you add this you are just making a crappy soil. Promix is technically ‘soilless’ and has to be supplemented entirely by the grower. This means you should be on a proven cannabis nutrient line (I use General Hydroponics) and follow the published schedule data.

This medium is already PH buffered for cannabis so adding stuff is really not the best idea.

Watering can cause issues if the plant is small in a large volume of media: it won’t dry out well at all. When the plant canopy is small you have to water small. Once the drip line of the plant equals the diameter of the pot then you can start watering to runoff.

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@Myfriendis410
Yes that’s it.
I follow what you’re saying. I came across a cpl of post here where they were saying they add perlite and worm castings . I tried it, not working so well.
What’s the best container to start seeds in?
So you don’t add anything to the Pro-Mix but what, ph’d water at what ph?
Thank you

There’s no best method. There are numerous proven methods. I use seedling trays for higher volume stuff, and rapid-rooter type plugs for higher value crops or anything going into hydroponics. All of them go into a high-dome vented seedling tray with a heat mat underneath.

It’s important that you understand that ProMix BX is not soil, and it does not have available nutrients. The mycorrhizae in there assist in rhizome development and nutrient delivery; however, you need to add all of the nutrients. Typically, this is done during waterings.

@Myfriendis410 explained this, and recommended the General Hydroponics line. I second this. Be careful to follow the mixing procedures to the letter. They will inform you about pH as well.

Good luck!

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The perlite is added to fight compaction really, but it would have less water retention with perlite than without. As far as adding worm castings alone, I really don’t feel like that’s the norm. And I probably have as much read time as anyone here.

Most people who grow in promix do so because it has limited amounts of amendments. That means they are feeding by hand or using an automated system to do just about all of the feeding. Promix definitely doesn’t have the nutrient load to maintain plants on it’s own.

Promix could be used as a base to build a soil, but it would need a lot more than worm castings to cover plant needs on its own.

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