| Abstrakt: |
Cover crops add organic matter, improve soil fertility, prevent soil erosion and compaction and suppress weeds, but they can be difficult to manage at the home garden scale. Because incorporating the entire cover crop into the soil with garden tools can be problematic, two alternative strategies were explored: 1. clipping and removing aboveground vegetation before spading. 2. killing winter annual cover crops by mowing after they flower. Seven winter annual grasses and one legume [hairy vetch (Vicia villosa Roth.)] were evaluated. Roots + stubble of winter rye (Secale cereale L.) were easy to spade in late spring once the top growth was removed. Italian ryegrass (Lolium multiflorum Lam.), field brome (Bromus arvensis L.) and 'Blando' Brome (Bromus mollis L.) gave better ground cover than rye but their roots + stubble were much more difficult to spade. Rye could be controlled by clipping close to the ground after it began to shed pollen in late May, whereas ryegrass, field brome, Blando brome and annual bluegrass all regrew. Triticale (Triticum X Secale) and five early varieties of winter wheat (Triticum aestivum L.) all shed pollen later than rye, which suggests that they could not be mow-killed as early in the season. Rye + hairy vetch mowed just prior to transplanting tomatoes (Lycopersicon esculentum Mill.) in May or early June provided a moisture-consering, weed-suppressing mulch through the growing season. Additional mowing between plants was needed to control rye regrowth, but a single late-spring cutting to a low (2-in) stubble height has prevented regrowth of rye + vetch in other studies at the same location. Early-season tomato yields were lower in mowed than in soil-incorporated rye + vetch, possibly because the mulch cooled the soil and delayed mineralization of nitrogen. However, the mulch did not significantly lower total yields, and it saved labor on weeding, conserved soil moisture, and possibly reduced fruit cracking. [ABSTRACT FROM PUBLISHER] |
