Abstract
High tunnels are an important season extension tool for horticultural production in cold climates, however maintaining soil health in these intensively managed spaces is challenging. Cover crops are an attractive management tool to address issues such as decreased organic matter, degraded soil structure, increased salinity, and high nitrogen needs. We explored the effect of winter cover crops on soil nutrients, soil health and bell pepper (Capsicum annuum) crop yield in high tunnels for 2 years in three locations across Minnesota. Cover crop treatments included red clover (Trifolium pratense) monoculture, Austrian winter pea/winter rye biculture (Pisum sativum/Secale cereale), hairy vetch/winter rye/tillage radish (Vicia villosa/ S. cereale/Raphanus sativus) polyculture, and a bare-ground, weeded control. Cover crop treatments were seeded in two planting date treatments: early planted treatments were seeded into a standing bell pepper crop in late Aug/early September and late planted treatments were seeded after bell peppers were removed in mid-September At termination time in early May, all cover crops had successfully overwintered and produced biomass in three Minnesota locations except for Austrian winter pea at the coldest location, zone 3b. Data collected include cover crop and weed biomass, biomass carbon and nitrogen, extractable soil nitrogen, potentially mineralizable nitrogen, microbial biomass carbon, permanganate oxidizable carbon, soil pH, soluble salts (EC), and pepper yield. Despite poor legume performance, increases in extractable soil nitrogen and potentially mineralizable nitrogen in the weeks following cover crop residue incorporation were observed. Biomass nitrogen contributions averaged 100 kg·ha21 N with an observed high of 365 kg·ha21 N. Cover crops also reduced extractable soil N in a spring sampling relative to the bare ground control, suggesting provision of nitrogen retention ecosystem services.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 171-180 |
| Number of pages | 10 |
| Journal | HortScience |
| Volume | 57 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 2022 |
Bibliographical note
Funding Information:Received for publication 7 May 2021. Accepted for publication 21 Sept. 2021. Published online 5 January 2022. Support provided from the NRCS Conservation Innovation Grant program 69-3A75-14-249 and SARE Graduate Student Grant GNC16-232. Portions of this text were used in the thesis “Legume cover crops in high tunnels: Field evaluation for soil health and controlled environment freezing tolerance” in partial fulfillment for Master of Science degree of Elizabeth Perkus at the University of Minnesota. We thank Steven Poppe, Thomas Holm, Dawn Ilhe, Keith Mann, Kimon Karelis, and Danielle Sackett for their assistance in managing field plots, and Tricia Bross, Peter Clay, Steve Moore, and Rhys Williams for their high tunnel expertise. Michelle Dobbratz, Peyton Ginakes, Fucui Li, Alex Liebman, Sharon Perrone, Dan Raskin, Than-walee Sooksa-nguan, Charlotte Thurston, and Vivian Wauters provided project analytical support, and Caitlin Barnhart, Bruna de Bacco Lopes, Rachel Brann, Kathleen Hobert, Victoria Hoepp-ner, Victoria Hoffman, Kaleiilima Holt, Siwook Hwang, Bonsa Mohamed, Justin Panka, Yordanose Solomone, Emily Swanson, and Loren Weber assisted in sample collection and preparation. J.M.G. is the corresponding author. E-mail: jgross@ umn.edu. This is an open access article distributed under the CC BY-NC-ND license (https://creativecommons. org/licenses/by-nc-nd/4.0/).
Publisher Copyright:
© 2022 American Society for Horticultural Science. All rights reserved.
Keywords
- Legume
- Nitrogen
- Organic agriculture
- Pisum sativum
- Trifolium pratense
- Vicia villosa
