[Maj.PotHead]

friend of mine brought over some used grounds from starbucks, guess they keep a room full in the back for ppl and thier house plants and such.

any1 use used coffee grounds during the grow as a soil amendment
will the used grounds effect the soils ph
should they only be used during veg, or can flowering also be included
it says right on the bag great source of N for your garden im just wondering thx for any experinced replys

[sproutco]

I would think that they are acidic. They are 2.08-.32-.28 n p k

[Farmer Joe]

I think they are very acidic as well. Never used them.

[supermanlives]

i put cofee and tea grounds in the compost pile and worm farm. never used them directly in soil mix without first composting or letting the worms munch on em.

[akornpatch]

very acidic...great for african lillies. LOL

Compost first...great idea.

use ASAP, they dont store fresh very long.
and lime them before m,ixin into yer containers,
but its non burning and fast release N if u need to top dress
or dont want to piss on yer plants.
composting first is a good idea, yeah.

btw i mean inside.
outside you can top dress about now
when the plants are stretching, but again, lime em first.
have fun

[3BM]

I have to disagree with some of the suggestions here. The acidity in ground coffee is mostly soluble, and thus used grounds have been largely neutralized by running hot water through them. Test the pH of the grounds you have but expect them around 6.5, slightly but not too acidic. Liming any material will cause it to loose N in the form of gaseous ammonia, so avoid it in compost piles. Besides, in my experience cannabis prefers acidic soil (6.2-6.6), so the acidity is welcome. Lime is often overused in soil mixes, and should only be added to soil below this range (unlikely unless one consistently adds acidifying material). Worms will eat the grounds up, and they are great in compost. Their fine texture means they heat up fast and break down quickly. I call it "urban manure".

[Verite]

Not sure if you want to use them in veg considering they are very high in P.

Material N P K
(%) (%) (%)
Alfalfa hay 2.5 0.5 2.0
Blood meal 15.0 1.3 0.7
Bone meal 4.0 21.0 0.2
Coffee grounds (dried) 2.0 36.0 0.7
Cornstalks 0.7 0.4 0.9
Cottonseed meal 7.0 2.5 1.5
Dried blood 12.0 3.0 0
Peat 2.0 0.3 0.6
Sawdust 0.2 0.1 0.2
Wood ashes 0 1.5 3.5

https://www.uidaho.edu/wq/wqfert/cis922.html

[NPK]

I bring home garbage bags full of grounds, filters included, for my compost. It's great! It attracts worms and gives your compost a wonderful texture. They're acidic, though I couldn't tell you what they might measure...now I'm curious.