Jack’s 20-10-20

I’m in the process of switching over from RDWC to Bruce bugbees peat/vermiculite blend.

I’ve built the soil exactly like he stated. I’ve looked and I can’t find anyone that’s actually used Jacks 20-10-20. Or any other 20-10-20 for that matter. I see people are using jacks 321.

I built Bruce’s blend for my vegetable garden this year and used jacks 20-10-20 with great results.

Has anyone actually used the 20-10-20? I’m assuming it’s missing things the plant needs and that’s why nobody has used it. Just trying to figure this out before I pop some seeds.

Thanks in advance.


@Hellraiser might be able to help you. Dr. Bruce is awesome! I just use jacks 321


I was planning on using it but after looking into it some, found that most cannabis growers that use Jacks was using the 321 recipe so went with that instead. But the good doctor Bruce Bugbee uses it at 1.3 EC/650ppms from sprout to harvest every watering so I’m sure it’s fine, specially when using his mix.


Works fine? Seems a touch low.

I use it from transition to harvest on autoflowers after fighting with the cal nitrate levels from the 321. Bloom is crushing ish in my book. So now I run 321 for most of auto veg then swap…add cal mg and let it ride. It’s working out rather nicely. This is her under a hlg 100 v2


What I thought as well but I did a whole grow using Jacks at 1.3 EC just to see and it worked fine on a solo cup challenge plant, watered multiple times a day, never saw any deficiencies. I just mixed up Jacks 321 as usual and then added RO water until it was at 1.3 EC/ 650 ppms. Worked very well.

Plant shortly before harvest after a week or so of water only.


Here’s my strawberry nuggets x Skywalker auto also. Just got put on boost.

The autos dont need much at all I tell ya. And when you go too far with the N from the cal nitrate it takes FOREVER to try undoing it. Here’s some nug shots of the strawberry mango crumble. We like day 65 rn I imagine shes gonna go 100 something :tired_face: but I have seen these ripen extremely fast.


Very nice!

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Thanks bro. Shes starting to burn a little which is crazy. Like you I’m running 1.2 -1.4 the whole run relatively flawlessly. Shes now at.7 EC and the burn just started so reflecting on my next move. Gotta stay on top of these res changes imo.

Awesome, thanks guys. I have cal mag from running hydro. Is there anything else you suggest I should get. Just in case some deficiencies show up? I’d also like to use guano, do you see any problems with that with the 20-10-20?