During the late summer and early fall, we can still find attractive colors in our gardens. Today’s column includes examples of such late bloomers, which continue to enhance the landscape while appreciating the season’s early rains.
Winter-blooming plants are available for the Bay Area climate, but the fall and winter months often direct our attention to the foliage plants. We enjoy the hues, unique forms, and pleasing fragrances of our flowering plants, and depend on the structures, textures, and colors of our trees and shrubs. Foliage provides the foundation — and often the background — of the landscape.
Today’s column focuses on planning for the fall season when we prioritize moving and adding plants to the garden. This priority reflects the plants’ typical growth cycle, which directs energy to root development during the fall and winter and prepares for leaf and blossom production during the early spring.
There are exceptions to this cycle, as with many aspects of plant cultivation, but a large percentage of familiar garden plants follow this seasonal process.
Gardeners are well-advised also to follow this process by installing plants in anticipation of the onset of our rainy season. As we noted in a recent column, our rainy season begins historically on Nov. 5, with a gradual increase in rain possibilities during the preceding weeks.
Last weekend’s light rain was a welcome precursor to our rainy season.
Here are suggestions for adding plants to the garden.
We recently recommended “gardening by walking around” to identify areas that need improvement. This process should include making a list of areas that could be improved by the addition of new plants. These areas might be existing gaps in the landscape or gaps that you create by removing pants that are under-performing or that you no longer enjoy.
A current project
My own plans include removing a fairly large cluster of Giant Rockfoil (Bergenia cordifolia Apple Blossom’). This plant is also called Pigsqueak because of the noise produced by rubbing a leaf between the thumb and finger. This desirable groundcover plant grows well in two areas of my garden and spreads slowly. My target cluster has developed to fill an area of about eight feet by eighteen feet.
I will uproot all of the Pigsqueak to share with a gardening friend and the Santa Cruz Plant Exchange.
This will free the partially shaded space under a large Mock Orange shrub (Pittosporum tobira). This area is well suited for relocating the bulbs of another plant called Blood Lily or Cape Tulip (Haemanthus coccineus). This South African succulent plant has been propagating itself for a few years and would benefit from more space. We will discover how many bulbs have developed and relocate them about two feet apart.
At this time, the Blood Lily is at the end of its bloom season and will develop its striking display of huge leaves by the early spring. It prefers to grow in place, so moving the bulbs might interrupt its cycle, but yield long-term benefits.
Thematic plant selection
Once you have identified areas that need new plants, adopt a plan for plant selection. As we have recommended in previous columns, acquiring plants to implement a thematic plan can support the plant selection process. That process can be frustrating when choosing from the large and ever-increasing array of options at the local garden center, plant catalogs, and the Internet.
This approach could adopt any of the many available themes, depending on the gardener’s personal preferences. Themes could be based on plant genus, blossom color, native origin, bloom period, or nostalgia. The point is to have a concept for the development of a specific garden bed.
Schedule your plan to install new plants in advance of the rainy season, to welcome nature to support the plants’ root development.
Mulching the garden
This season is also a good time to consider mulching your garden beds.
Anna Burke listed six reasons to mulch your garden now to protect it during the winter months.
- Lengthens your growing season.
- Retains moisture in the soil.
- Controls fall and spring weeds.
- Stabilizes soil temperature.
- Protects roots from heaves
- Increases organic matter.
This article was posted on the Dave’s Garden website (davesgarden.com).
There are several ways to mulch a garden. The easiest approach, shallow mulching, installs a single layer of brown mulch (e.g., fallen leaves or wood chips) of four-to-six inches. A better approach, deep sheet mulching, uses alternating layers of brown mulch and green mulch (e.g., freshly clipped grass) on a layer of paper (newspaper or cardboard), reaching a total depth of up to two feet or more.
There has been some debate about including a paper layer under organic mulch. Some research concludes that such a layer smothers weeds (as intended) and also smothers the soil, reducing the carbon dioxide and oxygen levels lower than desired, potentially affecting soil microorganisms. Other research acknowledges the reduction but concludes that it is not great enough to harm soil microorganisms or plant roots.
This debate is included in Jeff Gilman’s helpful article, “What is Sheet Mulching and How Do You Do It?). His article, published recently by Fine Gardening magazine, is available online at tinyurl.com/2p4yx4jb.
Advance your gardening knowledge
The Cactus and Succulent Society of America will present the webinar, “A glimpse of the Natural Beauty of Chiapas,” at 10 a.m. Oct. 1. The presenters, Julia Etter and Martin Kirsten, will provide a sightseeing tour of Agaves and Crassulaceae in the Mexican state of Chiapas. These are popular succulent plants for Monterey Bay area gardens. To see more information and register for this free event, browse to cactusandsucculentsociety.org/.
Fine Gardening magazine (one of my favorites) has posted a series of recorded webinars on gardening topics. Selected subjects that relate to today’s column and other recent columns include New Plants That Deserve Your Attention, Underrated Spring-Blooming Bulbs, and Creating a Garden Vignette. Check them out by visiting the website, finegardening.com/section/webinar/.
Enjoy your garden!
Tom Karwin is past president of Friends of the UC Santa Cruz Arboretum and the Monterey Bay Iris Society, a Lifetime Member of the Monterey Bay Area Cactus & Succulent Society, and a Lifetime UC Master Gardener.