In the Garden
Ralph Purkhiser, Purdue University Master Gardener
The rains during the past week have brought down most of the leaves, and the remaining leaves will likely be falling soon. These November rains are a blessing. While drought conditions plagued southern Indiana for most of October, November has brought some much-needed moisture. This is important, since plants need to have adequate moisture to prepare for the coming winter. Even though the tops of trees, shrubs and perennials may seem to be sleeping, there is still active growth in the root system, and this will continue until the ground freezes. This is especially true of recently-planted plants. The moisture is needed to allow them to produce a good root system, which will anchor them through the winter. One of the greatest challenges for plants in an Indiana winter is heaving, caused by the freeze-thaw cycles that typically occur. This heaving will actually cause the root system to be lifted out of the ground. If the root system is not extensive, the whole root ball may be lifted, and if this is not corrected, the plant may be killed during the next freeze. That is the reason one should wait until a freeze, and then apply a layer of organic mulch, to insulate the ground and keep it frozen. That will prevent heaving.
This heaving is also one of the reasons that gardeners should inspect their gardens regularly in the winter, especially any time there is no snow cover. If one finds plants that have been heaved out of the soil, they need to be pressed back down in the soil. Mark them and apply mulch during the next freeze.
Those fallen leaves are a source of much controversy in the gardening and naturalist world. To be truly natural, the leaves should be left to decay in place, enriching the soil and providing organic material. However, heavy leaf cover may smother grass and other plants. The leaves also provide shelter for many insects.
You have many options for leaves, and I leave it to each person to choose what works best in his or her situation. I use different methods in the various parts of my garden. In the wilder areas near the woods, I usually just leave the leaves. However, wet leaves can become a problem in areas where I will be walking during the winter. I choose to use a leaf-vac to clean walkways and the leaves that blow onto decks and porches. This device shreds the leaves as it picks them up, and that will likely kill the insects in them. Still, these shredded leaves are put to good use. I will apply them to my raised garden beds, where they will decompose over the winter and add organic material to the beds. In the grassy areas of the garden, I usually pass over the leaves with the lawn mower. This shreds the leaves and the resulting leaf cover is usually not heavy enough to kill the lawn. In other areas, I rake the leaves into the many perennial beds, using them as mulch. I also have to remove leaves from the drainage ditch along the county road. These leaves are often wet and matted together. I make a pile for them in an area at the edge of the woods. By spring, they will have become a wonderful leaf mold that I can use as mulch in the gardens. There are two common leaf-removal options that I do not recommend. In some areas, it may be necessary to bag leaves, but I find that to be a great waste of organic matter. Most landfills no longer allow bagged leaves and yard waste. Some municipalities require that leaves be bagged in paper bags that will break down and add to the organic material. The worst leaf-disposal option is burning. This will kill all sorts of insects and add to air pollution. It also is a terrible waste of good organic material that will feed the soil.
If there are children who play in your yard, please rake at least one big pile of leaves and let them jump in them. Every child needs to experience the joy of leaf diving.