Plant Now for Your Fall Garden
By Virginia Hayes
There’s just a hint in the air, a slightly different cast to the light; yes, fall is on the way. For gardeners in Southern California, this is the cue to set about getting a number of gardening chores done. The most rewarding may be planting new bulbs, perennials, and woody plants. While much of the country is putting their gardens to bed, here fall is one of the best times to establish new plants while the soil is still warm and the days still long enough to foster good growth of roots below the surface of the ground. Because the soil is nice and warm, all the organisms that can form symbiotic relationships with rootlets, such as mycorrhizal fungi, and bacteria that liberate nutrients from organic matter are still multiplying full tilt. They will assist the plant in getting a good toehold now before the cycle slows down as soil temperatures drop. Come spring, these plants will outperform similarly sized ones planted into the cooler soil. This window of opportunity will last for at least the next two months, so if you aren’t quite ready yet, there is time to plan and still take advantage of the season.
This regime is good for a wide range of plant types. Among them are those that come from other Mediterranean climate zones. Many plants native to South Africa, Australia, Chile, and the Mediterranean area as well as some California natives have been in a somewhat dormant state through the warm, dry summer months. They are adapted to take advantage of the coming cool spell by starting a growth spurt in anticipation of the winter rains ahead. This is a magic moment in their life cycles that embraces the lingering fall warmth and, with our help, some supplemental watering to get them off to a good start. A short list of candidates for immediate planting follows:
Bulbs and other tuberous plants: anemone (Anemone coronaria and A. fulgens selections), freesia, ranunculus (Ranunculus asiaticus), Babiana stricta, Narcissus (daffodils and paperwhites), Hippeastrum (also known as amaryllis), and Watsonia.
Perennials: yarrow (Achillea species), Alstroemeria, Japanese anemone (Anemone ×hybrida), kangaroo paws (Anigozanthus), snapdragon (Antirrhinum majus), snow-in-summer (Cerastium tomentosum), chrysanthemum (Dendranthema ×grandiflorum), sea holly (Eryngium fastuosum), Gaillardia grandiflora, Gazania hybrids, Corsican hellebore (Helleborus argutifolius), coral bells (Heuchera species), penstemon, Phygelius species, California fuchsia (Zauschneria californica).
Shrubs: Acacia species, manzanitas (Arctostaphylos species), Banksia species, Callistemon species, Ceanothus species, rockrose (Cistus species), Canary bird bush (Crotalaria agatiflora), pride of Madeira (Echium fastuosum), Eucalyptus species, Grevillea species, lavender star flower (Grewia occidentalis), lavender (Lavandula species), tree mallow (Lavatera species), Melaleuca species, honeybush (Melianthus major), barberry (Mahonia species), oleander, plumbago, scurfy pea (Psoralea pinnata), coffeeberry (Rhamnus californica), rosemary, Westringia fruticosa.
Trees: peppermint tree (Agonis flexuosa), carob (Ceratonia siliqua), Eucalyptus, olive, Pittosporum species, oak (Quercus species), Afrocarpus/Podocarpus species.
All those plants are going to be around for years to come, but there are always ephemeral species that can fill the garden with color and beauty for just one season. The annuals that will be coming into their own through the cool winter months and, therefore, must be started soon can also be started from seed or small plants. The classics are: stock (Matthiola majus), sweet alyssum (Lobularia maritima), calendula, English daisy (Bellis perennis), foxglove (Digitalis), godetia (Clarkia amoena), Iceland and Shirley poppy (Papaver species), nemesia, pansy (Viola), and short season sweet peas. If you start these you may have flowers for Christmas.
The other big chore right now is making sure that tropical plants accustomed to year-round rain get the regular water that they need to perform well. This summer has been extremely unusual in the amount and distribution of rain that has fallen on the South Coast. It fell all through April as if it were March and then, not just measurable, but significant rain fell in May, July, and even August this year. Nevertheless, there are plants that are definitely more suited to a year-round watering regimen, such as citrus trees, that still need some extra TLC right now (don’t complain, just think of all the irrigating you didn’t have to do this summer). Without regular water, some plants won’t have the resources to flower and fruit well. Camellias, in particular, need to have a consistent supply of water now while they are forming their flower buds. Between the normal dryness of the season and the potential (if not inevitable) Santa Ana winds, camellias can really suffer during the fall. The soil needs to be maintained at a consistently hydrated state for them to weather the next few months. If it isn’t, the buds will turn brown and drop off. This is bad for the floral show next spring, but could also impair the general health of the plants. Soil probes can be an invaluable tool to monitor soil moisture so that an appropriate watering regime can be maintained not just for camellias, but all your garden beds.
It is easy to see the smaller plants in the garden reacting to weather patterns, but sometimes it is harder to see what’s happening to larger or older trees and shrubs. A good policy is to deep water redwoods, Monterey cypresses, palms, citrus, and other subtropical or tropical plants at least once a month through the summer and fall. Citrus trees that don’t get consistent water will produce spongy, tasteless fruit, for example. It’s never too late to start. And, be especially mindful of those tropical plants that you just planted in the last few months. Bougainvillea, hibiscus, philodendron, gingers, and many others will need your attention to assure their success through this warm, dry time. If the fogs have really gone, you may also want to mist or spray the more tender plants and increase the overall humidity for their well being. Keeping them well-grown and healthy will also ensure that they do not succumb to the late summer pests such as spider mites and the ever-present giant whitefly.
Fall is one of the nicest seasons on the South Coast. Gardening will give you one more good excuse to be outdoors enjoying it.
Virginia Hayes, curator of Ganna Walska Lotusland, will answer your gardening questions. Address them to Gardens, The Independent, 122 W. Figueroa St., S.B., CA 93101. Send email to firstname.lastname@example.org.