Turn over a new leaf by turning leaves into compost.

Gardeners are encouraged to compost leaves this fall to improve soil health. With plenty of leaves, grass clippings and garden debris available, residents can create compost piles that benefit the environment, recycle yard waste and nourish their gardens.

“Composting is a natural process that turns organic material into a dark, crumbly, earthy-smelling material called humus,” said Aaron Steil, consumer horticulture specialist with ISU Extension and Outreach. “It is an excellent soil amendment that improves soil structure, increases water-holding capacity and provides nutrients.”

Building and maintaining a compost pile

Effective composting requires a balance of carbon-rich “browns” (such as dried leaves and straw) and nitrogen-rich “greens” (like vegetable scraps and fresh grass clippings). The ideal carbon-to-nitrogen ratio is about 30:1. Steil recommends piles be at least three feet tall and wide to retain heat and should be turned regularly to maintain airflow and moisture.

“A three-bin system can work well with one bin used to stockpile materials until there is enough material to begin a composting batch,” said Steil. “The second bin is used for active composting and the third is used for the finished material to be stored until it can be used.”

Decomposition will still occur when the ratio of carbon to nitrogen is not perfect, but at a slower rate. “Compost created from fall materials, like fallen leaves and dead plant debris, is high in carbon and low in nitrogen. This means that special attention needs to be given to provide more of those green materials to create compost efficiently,” Steil noted. To accelerate the decomposition rate, gardeners can shred materials to increase the surface area for microorganisms to feed upon. Adding a small amount of nitrogen-rich fertilizer can also help. Regularly turning the compost helps introduces oxygen, keeping microbes healthy and growing. If the pile is dry, Steil advises adding water until it feels like a “wrung-out sponge.”

Steil recommends avoiding the use of meat, dairy products, pet waste, weed seeds and diseased plants in compost to prevent pests, pathogens and weeds. While heat is generated during the composting process, temperatures need to reach 150 to 170 degrees Fahrenheit to kill most pathogens and weed seeds, and most home compost piles do not reach this high a temperature.

“If a gardener does a great job of balancing the right ratio of browns and greens and provides the right amount of moisture while turning frequently, the pile will be warmer,” Steil said. “But even with the best of conditions, the pile may not be hot enough for long enough, so it’s best to avoid seeds and diseased plants.”

Using finished compost

After several months, compost should resemble rich, dark soil with an earthy aroma. This finished product can be used to top-dress lawns, mulch around trees or improve garden beds for spring planting. While compost can introduce some fertility to soil, its real benefit is introducing organic matter. Compost’s ability to improve soil structure and water-holding capacity improves aeration, supports the beneficial soil microbe population and helps the soil better hold and release essential plant nutrients. “This is why we sometimes call compost black gold!” Steil mentioned.

K-State horticulture expert outlines steps to protect plants during colder months.

November’s temperatures in much of Kansas have proven to be unseasonably warm, but rest assured, the colder days of winter are not far away.

For gardeners, that means giving attention to garden plants in order to protect them from the inevitable freeze.

Kansas State University horticulture expert Cynthia Domenghini shared tips for protecting two popular plants – roses and strawberries.

Winterizing roses

Most shrub roses are hardy through Kansas winters, but many hybrid teas and other modern varieties require protection, Domenghini said.

“It is important to winterize roses after several hard frosts have occurred, but before the ground freezes,” she said. “Winterizing too early keeps the stems warm and moist, which promotes the growth of mold. Winterizing too late risks damaging the sensitive graft union where the root stalk attaches to the above-ground growth.”

To prepare the plants for winter, clean up debris in the area surrounding the roses to prevent diseases from overwintering. Mound soil or compost 8-10 inches high around each rose plant. Domenghini said this is also a good time to bring in new soil – instead of soil around the roses – to avoid exposing and damaging the roots.

Once the ground has frozen, add a four-inch layer of straw, leaves, wood chips or other mulch over the mound, and cover with a layer of soil to hold it in place.

“This will help protect plants from the cold, but also prevent early budding during warm winter and early spring days,” Domenghini said. “As the mulch settles during winter, you may need to add more.”

Prune canes to 36 inches and remove weak or thin canes. Tie the remaining canes together loosely to keep them secure during windy weather. “If the canes are allowed to whip in the wind, it can cause damage to the crown and disturb the soil,” Domenghini said.

When the ground thaws next spring, remove the mulch and soil from the base of the plant to return the soil level to normal.

Winterizing strawberry plants

Mulch is necessary to protect strawberry plants from winter damage, regardless of whether they are young or established, Domenghini said.

“Sudden drops to freezing can kill fruit buds and injure roots and crowns,” she said. “When the soil freezes and thaws repeatedly, plants can be heaved out of the soil, exposing the roots.”

Domenghini recommends a three-inch layer of straw mulch for plants after they have been exposed to several frosts, but before the heavy freeze begins. In Kansas, this usually falls between Thanksgiving and Christmas.

More information on caring for strawberries is available online in a publication from the K-State Extension bookstore.

Domenghini and her colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens.

Interested persons can subscribe to the newsletter, as well as send their garden and yard-related questions to [email protected], or contact your local K-State Extension office.