I got a straw bale down to my garden, no not by dog sled, I pulled it, and now I’m looking into conditioning it so I can plant in it. It’s the first time I’ve tried straw bale gardening. It seems like a perfect solution to planting peas early – despite our late snow cover this year in New England.
What I read is that I need to water my bale for about 3 days. This starts decomposition inside the bale and it gets hot. I can either wait several weeks, or speed up decomposition by adding a nitrogen source every few days and continuing watering. With the nitrogen added, after 10 days the bale will be ready for planting seeds.
But I have to admit that I don’t understand several things. Why is the heat of the initial decomposition a problem? It’s freezing cold outside so how can it get too hot now? Its seems heat would be good for the plants now.
In addition, I’m thinking that the peas I will plant can fix their own nitrogen, well with help from the Rhizobium bacterial inoculant I’ll add when I plant them, so why do I need to worry about adding nitrogen to the hay bale?
I want to understand exactly what’s going on in the conditioning process. Explanations I find generally seem vague and the process seems almost magical.
This site seems to get at a better explanation: Oklahoma Coop Ext
“…if seed or seedlings are planted into a fresh bale, microbes in the bale will use any nutrients present to breakdown (or decompose) the straw depriving the growing seedlings of nutrients such as nitrogen, phosphorus and other essential elements”
Ah, so the decomposition process is doing more than producing heat, it’s tying up phosphorus and other nutrients that pea plants will need. Fortunately it only lasts a short time in the bale. Decomposition of other materials takes years and I know can be a problem if it takes place in soils where plants are trying to grow.
Well that makes more sense to me. I’ll start to add nitrogen. Good organic nitrogen sources are blood meal and fish emulsion. I have a nice fish emulsion. I’ll try to get down to the garden to add this today, and I’ll see if its really hot inside the bale. Fortunately we’re getting nice rain soon, so I don’t need to carry water.