It is often easy to forget about our gardens once the blooms have disappeared, foliage has wilted, fall leaves start dropping and the season turns our thoughts to holidays and other things, rather than gardening. But for those who take advantage of the cool autumn days to clean up and prepare the garden for winter (and spring), the benefits are many: a tidier landscape, protected and rejuvenated plants, and improved soil. With that in mind, here is an autumn garden checklist:
- Get rid of diseased perennial leaves and entire plants if necessary.
- Remove spent crops and, if no disease is present, chop up and put in your compost pile.
- Pull the season’s last weeds.
- Dispose of all diseased plant debris in the garbage, not in your compost pile.
Cut Back and Prune
While many perennials, shrubs and trees benefit from a late fall or winter trim (or even radical pruning), the best wisdom here is to take the time to research each plant to determine what it prefers. Other things to consider:
- Resist the temptation to trim or prune while the weather is still relatively warm, even though technically speaking, it is autumn. The reason is, cutting back before the weather has triggered dormancy often causes the plant to send out new, tender growth, as in spring.
- If you have perennials such as coneflower and yarrow that produce significant seed heads, consider leaving them on until late winter or spring. The birds will enjoy the feast.
- Some perennials are best when cut back to the ground in order to remove spent foliage that tends to harbor disease. Peonies are a good example. Once their leaves wilt and turn yellow, botrytis blight, a common fungal disease, can attack.
Applying or adding to mulches in the garden before the first hard frost helps to:
- Protect the roots and crowns of perennials by insulating the soil.
Prevent soil compaction from heavy rains (let us hope for rains!).
Help stop erosion from heavy rains and wind.
- Enrich the soil as it decomposes.
Improve Your Soil
Fall is a great time to enrich your soil, because you can dig among plants when they are moving into dormancy.
- Incorporate organic matter to help set into motion the natural cycles that enrich the soil. Some examples of organic matter include compost, straw, grass clippings, shredded leaves and composted or aged manures.
- To be effective, large amounts of organic matter are necessary, about one-third of soil volume. Work a two- to four-inch layer of materials into the top one foot of soil. But do not cultivate soil when it is wet, as it can damage soil structure.
- If your soil needs amendments, use a 100 percent organic fertilizer, and fork it into the top three to four inches of soil.
Once you have put your garden to bed for the winter, curl up on the couch with a good garden catalogue and plan next year’s additions!
Rachel Oppedahl is a University of California Cooperative Extension Master Gardener of Tuolumne County who loves poring over gardening books and seed catalogues in winter almost as much as planting in spring. For any home gardening questions, you can call the UCCE Master Gardeners of Tuolumne County hotline; 533-5912 or email: firstname.lastname@example.org.