Do not apply fresh high-N fertilizer to root crops.
Promising A person has checked it against its sources. If you skip this, it still grows, just less well. The planner suggests it.
How it works
Excess N drives foliage at the expense of root bulking. (Forking is a separate problem, caused by rocks, compaction, or coarse/fresh organic matter in the root path. Nitrogen does not cause it.)
The evidence
Evidence: checked against 2 sources in the research-based literature.
The 2 sources
Excessive nitrogen fertilization can also contribute to lots of leaf growth at the expense of root growth
… excess organic debris such as woodchips worked into the soil just before planting also may affect root penetration, causing forked and twisted roots
Plants it applies to · 6
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How this rule has changed
Every change is dated, newest first. The full record, with each reason, is in the data download.
- Sources updated
- Wording made clearer
- A person read the sources and confirmed it
- Added to the rules
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Cite this page
Milpa Gardens. “Do not apply fresh high-N fertilizer to root crops.” Evidence grade: Promising. https://milpa.garden/rules/do-not-apply-fresh-high-n-fertilizer/
A garden planner built on graded evidence. Every claim states its evidence grade and links its sources on the page. Cite it with the grade, and add the date you read it.
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How we grade evidence
- Well established
- The rule names its mechanism and is settled, by sources a person has read and checked or by plain arithmetic and geometry.
- Promising
- The mechanism is named and the literature backs it. A few questions are still open.
- A good hunch
- Plausible by its mechanism, but field studies are thin, so treat it as a lean.
- Contested
- The evidence points both ways, or no study has tested it, so the planner does not enforce it.
- Refuted
- The claim did not survive its sources. It is kept so the folklore can be answered.