After a hot and surprisingly wet summer in the Piedmont, most gardeners were expecting a warm autumn. Not so, however. September was cooler than expected and October, through mid-month, was more or less average, though the end of the month has been surprisingly warm. The average first frost date for our hardiness zone 7a is October 15-25. If you want to keep sensitive plants healthy, you would be wise to have your row covers or other protective devices ready as needed while keeping an eye on the extended forecast. Nevertheless, it is time to clean up the garden, prepare for winter and take steps that will be of benefit next spring. Here are a few recommendations.
Cleaning and protecting your beds
Beds that no longer have a growing crop and will be idle this winter should be cleaned. Remove plants and plant debris. It can be composted if clean, but if it shows evidence of disease or pest infestation, it should be bagged for disposal or burned. It is too late now to establish a cover crop so covering soil with an organic mulch is the next best choice. Mulched leaves are a good and generally available option. Use the bagger on your mulching mower to collect chopped leaves, or mulch and rake them. Use them as a mulch to protect soil or mix them with grass clippings and kitchen scraps to start new compost batches. Chopping them up is important to allow water infiltration and reduce wind dispersal. They also break down faster, providing needed organic matter for the soil while reducing carbon loss, erosion and moderating soil temperature. Other mulch options include straw, wood chips and aged saw dust.
Cover Crops
Best soil building practice today is keeping live roots in the soil, year-round. Cover crops are a recommended way to do this when other crops are not being grown. A diverse winter-hardy cover crop is a great soil builder. The photo above shows a crop that includes crimson clover, a legume that will add nitrogen, daikon radishes that will loosen compacted clay soil, annual rye grass for added root mass and mixed grains. There is also some self-seeded buckwheat from the summer cover crop that will be winter killed but will add organic matter to the soil next spring so is a do-no-harm invader.
When cut before setting seed in the spring, the vegetative material can be tilled in as a green manure, composted or used to mulch transplants. The roots are left in the soil to decompose, adding more organic matter.
It is late to plant a cover crop now, but if you haven’t done it, consider planting one next fall. More information on cover crops can be found in the article Cover Crops from the U of Maryland Extension.
Extending the Growing Season for Cool Weather Crops
Winter hardy crops including many greens like lettuces, spinach, kale and other brassicas planted in September or early October, should be harvestable now. Mulching around the plants will help reduce cooling and keep them productive into the winter. Using row covers maintains a temperature beneath the spun polyester fabric up to 5 or 6° F higher than ambient, while still allowing rainfall and sunlight to reach the plants. For more information on row cover options including a simple DIY system like the one in the photo, see the article Row Covers: A Gardening Season Extender With Benefits from the November 2019 Garden Shed.
Adding Compost
A couple of inches of clean compost, worked into the top 3 to 4 inches of soil, then covered with an organic mulch will improve next spring’s soil readiness. Best practice is not to till deeply or turn the soil over, but to stir the compost into the soil surface, letting soil organisms decompose and carry the organic material deeper into the bed.
To habitual tillers, this seems counterintuitive. However, research and the experience of organic market farmers demonstrate that tilling destroys soil structure, reduces soil organism activity, and releases stored carbon to the atmosphere. Varying the crops grown in specific garden locations, using diverse cover crops, adding organic matter, and amending as soil tests indicate, are the best way to improve and regenerate soils.
Start a New Compost Batch
With the abundance of fall leaves, start a new batch of compost that will be ready for next summer’s garden. Final lawn mowing and leaf removal generate a great mix of nitrogen- and carbon-based organic materials to get decomposition started. Augment the nitrogen input it by mixing in kitchen fruit and vegetable scraps and coffee grounds during the winter. Microbial activity will definitely slow down during the dead of winter, but with a little mixing to keep it aerated and good moisture management, it will be primed to take off as temps rise above 50° in early spring. The finer you chop the materials, the faster they will break down. Check out this brochure on home composting from the VA Cooperative Extension for detailed guidance.
Prepare a New Bed
One circumstance where tilling soil may be useful is in starting a new bed. Loosening compacted soil and adding organic matter can be beneficial. However, sheet composting or lasagna mulching provides a non-dig alternative that may make sense for you. It involves scalping the grass off the bed area(s) and covering it with alternating layers of carbon and nitrogen rich materials. The layered material will cold compost over a few months, providing a carbon-rich surface that helps soil organisms flourish and carry organic matter deeper into the ground. Crops can be planted directly in the surface material. Starting the process now should provide you with a planting-ready bed for warm weather vegetables next spring. The photo above shows a sheet mulched plot using a paper barrier on the soil, covered with 6 inches of composted arborist waste and 3 inches of straw. For a detailed description of the process, refer to the Garden Shed article Lasagna Mulching
Other tips for the month include:
- Get your garden documentation in order. Knowing what you planted and where you planted it is important. Good crop rotation practice helps minimize disease and insect issues next year. Also, noting the crops and varieties that did and didn’t do well provides guidance as you shop for seeds and plants for next year’s garden.
- Root crops such as carrots, radishes, turnips, and parsnips store well outdoors in the ground. Just before the ground freezes, bury these crops under a deep layer of leaves or straw.
- If you are a fruit grower, November is a good time to mulch fruit trees. Extend 2-3 inches of mulch to the edge of their canopy, but keep it a few inches away from the trunk to prevent potential rodent damage.
- Early November is a good time to plant most new fruit trees. Mulch the same as for established trees.
- Fallen fruits should be cleaned up and buried or placed in the trash. Good sanitation practices reduce insect and disease infestation next year.
- Mulch strawberries with straw or leaves. This should be done after several nights near 20ºF but before the temperature drops into the teens. Apply the straw or leaves loosely but thickly enough to hide plants from view.
- Now is a good time to collect soil samples to test pH and nutrient levels. Organic amendments are slow-acting, so fall application improves soil for spring planting. Soil test kits are available at your local Extension Office. The Charlottesville-Albemarle Extension Office is located in the County Office Building on 5th Street Extended, 460 Stagecoach Road, Charlottesville. Kits and instructions are available in a box on a bench outside the front entrance.
- Disconnect, drain and roll up garden hoses. Best to do it before it gets cold and they get stiff and hard to handle.
- Drain rain barrels, outdoor water pipes and irrigation systems that may freeze during the cold weather.
- Rhubarb plants that are four years old or more can be divided and transplanted. Prepare the site by digging deeply and incorporating compost.
- Cut off the tops of asparagus plants to about 3-4″ above the soil level. Weed, and add a winter dressing of compost or aged manure to the bed.
- If you have been thinking about installing a deer fence around your vegetable garden, the fall and winter months are a good time to build it.
I hope you find this information helpful and that you will check in again next month. Comments are welcome.
Sources:
“Monthly Horticulture Tip Sheet: November,” VCE Monthly Horticulture Tip Sheets, Virginia Cooperative Extension, Albemarle County/Charlottesville.
“Monthly Gardening Tips: November,” Piedmont Master Gardeners website, Gardening Resources.
