Summer gardens tend to be bigger, size-wise, than fall/winter gardens, so it’s normal to be looking at some empty garden space during the off-season. Here are a few basic goals for that space:
- Protect the soil from compaction, erosion, and nutrient loss due to hard winter rains
- Suppress weeds, which can still grow through our not-so-fair winter weather
- Maintain and enhance soil structure
- Replenish organic matter and nutrients in the soil
In order to accomplish these goals, you might choose to use cover crops and/or sheet mulch. You probably have areas in your garden that could benefit from either or both method(s); here is a brief explanation of each, along with some of their benefits:
- Cover cropping (also known as “green manure”) uses winter-hardy plants that will be turned under in the spring to loosen and aerate the soil. It also adds organic matter and nutrients (primarily nitrogen), enhances soil microbial activity, and improves soil structure.
- Sheet mulching, which is also known as “lasagna gardening,” is a way to use slow composting in place to create planting areas; it is also an easy way to prep new ground in fall for planting in the spring.
Which areas can benefit from cover cropping/sheet mulching? Anywhere you have grown crops in the past and/or intend to grow crops in the future! You can throw small seeds around or drill medium-large seed in between existing plants and in cleaned-out beds, and sheet mulch around existing plants or over cut-short grass to create new planting areas.
Ideally, cover crops should be planted before the end of September: they need time to get established before cold weather hits, and planting early gives you more options for what to plant. You can sheet mulch up to six months before you need the space for planting. Sheet mulch doesn’t get hot like other composting methods, and it takes some time to break down into a good planting medium.
Cover crops can be used alone or in combination. If you plant them together, aim to plant a nitrogen-fixing legume with a tall crop for structural support, or use a pre-combined “garden mix.” Some good green manures for fall planting and spring removal:
- Hairy vetch—nitrogen-fixing legume
- Winter rye—winter-hardy grain that grows tall
- Crimson clover—shouldn’t spread like other clovers
For more information about winterizing your garden, check out this blog entry from last year. And at this key time of the year, keep up the good work!