Homebrewers Association | AHA Forum

General Category => General Homebrew Discussion => Topic started by: gigatropolis on June 25, 2011, 04:03:28 PM

Title: spent grains killed my plants??
Post by: gigatropolis on June 25, 2011, 04:03:28 PM
I did my first 5 gallon all grain last week and had 11 pounds of left over grains that I dumped into the flower pots on the back porch. One of the pots is a half barrel size with a large pepper plant that I dumped maybe 4~6 inches of the grains on the top of the soil. Now, the grains still had a lot of sugar because I only have a 3.5 gallon pot, and the grains started to stick after a few days. I watered the plants really good to try and wash some of the rotting sugars into the dirt.
  Anyway, what happened is the pepper plant and a young tomato plant ended up dying on me. All the have fell off and looks terrible.

  So could the spent barley grains have killed the plants? has anyone experienced this type of thing mulching with mashed grains before?

   Thanks,

kregg
Title: Re: spent grains killed my plants??
Post by: a10t2 on June 25, 2011, 04:17:27 PM
Spent grain has a fairly high nitrogen content. It's entirely possible that using too much of it could harm the plants, just like "burning them out" on a high-nitrogen fertilizer.
Title: Re: spent grains killed my plants??
Post by: ccarlson on June 25, 2011, 04:33:29 PM
When it starts to compost a lot of heat can build up and burn the plants.
Title: Re: spent grains killed my plants??
Post by: euge on June 25, 2011, 05:50:24 PM
And it might have changed the soil pH which matters a great deal.
Title: Re: spent grains killed my plants??
Post by: Will's Swill on June 25, 2011, 08:44:50 PM
Maybe they just really didn't like your beer.
Title: Re: spent grains killed my plants??
Post by: EHall on June 25, 2011, 09:24:09 PM
what temp were the grains when you dumped them in the pots? You could have actually 'burned' them in the heat sense...
Title: Re: spent grains killed my plants??
Post by: morticaixavier on June 26, 2011, 04:26:52 AM
Also holding too must moisture at the crown (top of root) can cause rot and death.
Title: Re: spent grains killed my plants??
Post by: gigatropolis on June 26, 2011, 05:23:37 AM
Maybe they just really didn't like your beer.

   That makes the most sense ;)

  The grains were still a little hot when putting in the pots, so I think maybe the smaller tomato was effected  but the pepper was a big bush with inch thick base so not likely. Too much nitrogen or PH change is possible.

 Guess the lesson is: compost your grains first before adding to plants

  Thanks for the replies
Title: Re: spent grains killed my plants??
Post by: majorvices on June 26, 2011, 01:08:46 PM
I've always composted my grains before mixing them into the garden, specifically because they can mess with the soil pH.
Title: Re: spent grains killed my plants??
Post by: malzig on June 26, 2011, 10:47:43 PM
Green grass clippings can do the same thing.  I don't know if it's all the heat they make decomposing or the pH.

Spent grains make great, fast compost, though, if you keep them well aerated.
Title: Re: spent grains killed my plants??
Post by: corkybstewart on June 27, 2011, 04:24:44 AM
Spent grains and most other stuff really needs to be completely composted before it's good for plants.  I killed a tree a few years ago with uncomposted stuff because I grew up in Mobile Al  and leaves and other stuff fall and decompose into very rich soil.  Apparently falling is the critical step because when I just put fresh leaves, grass clippings and spent grains on the ground it killed the tree.
Title: Re: spent grains killed my plants??
Post by: thomasbarnes on June 27, 2011, 12:59:26 PM
To expand on pH change, remember that your mash is going to be ~ pH 5.2-5.6. That's really acidic for soil.