Autumn is in full gear this month. This is a great time to plant almost any tree, shrub, perennial, ground cover, wildflower seeds and the last of spring-flowering bulbs. While the days are shorter and storms may affect our ability to work outdoors (we can hope for many such interruptions!), it is generally more pleasant both for us and the plants, as long as we follow some simple guidelines.
PLANTING: In the cool autumn weather, transplanted plants will experience less shock. If we haven’t received enough rain to saturate the soil, fill the planting hole with water and let it drain, just as you would other times of the year. Wait until spring to plant frost sensitive plants like citrus, avocado, bougainvillea, native plants from Baja California or the Channel Islands and many kinds of succulents from all over the world, or if you do plant, be prepared to protect them with row cover cloth or other methods through winter. This is an especially good month to plant those California and Mediterranean woody shrubs that don’t thrive with too much summer water. This includes manzanita, ceanothus, lavender, coffeeberry and buckthorn, bush lupin, flannel bush and rosemary. When planting trees, remove the nursery stake that comes with the plant and is wrapped closely to the trunk. If your new tree needs staking for a season or two, use bamboo or lodgepoles and proper tree ties and place the stake towards the outside of the root ball. The trunk should be able to move a little bit in breezes to strengthen.
November is the month to plant spring bulbs like daffodils and narcissus in a site where they will get a full day of sunshine at least through early summer. Purchase bulbs that are firm and without spots of mold. Plant the bulb three times deeper than its height. Usually, the pointed end of the bulb is placed up when planting. Add a handful of high-phosphorus fertilizer mixed with soil to the base of the planting holes. Natural sources of phosphorus are animal manure, bones, and bat guano. All spring bulbs should be planted by Thanksgiving.
If you grow dahlias, November is the month to dig and divide overcrowded tubers. Store them in a cool dry place until re-planting in February.
Early in the month, we can still plant winter vegetables like greens, broccoli, cauliflower, and cabbage. This is good since I am always late getting those last seedlings in the ground.
MAINTAINING: After the leaves fall, begin pruning deciduous shrubs and trees, not only to shape them, but to prevent storm damage. Our Master Gardener website has more complete instructions and illustrations on pruning trees the correct way.
Fall and winter blooming plants and vegetables can be fertilized. Do not fertilize California native plants. The exception is that you can provide your manzanita with a very weak dose of fertilizer for acid-loving plants like azalea and camelia. Do not fertilize avocado, citrus, palms, or other frost sensitive plants in the fall.
If your peach or nectarine tree had deformed leaves during the summer, it probably had “peach leaf curl”. This is a fungal disease that affects fruiting, and if severe, it can cause the tree to die. To control peach leaf curl:
- Rake leaves when they fall. Remove any mummies and discard. Do not add these to your compost pile.
- Spray trunk, branches, and the ground underneath the tree with a copper-based fungicide or a Bordeaux mixture (a slurry made of hydrated lime and copper sulfate). You can also use a synthetic fungicide. Products need to have 50 percent copper to be truly effective.
- One application is usually enough, however, if we have a wet winter, then spray again before the flower buds swell in the spring.
If you can, grind up pruned branches and leaves to use as mulch. But if you know your plant clippings have a disease or major insect issue, send those to the green waste and you will need to purchase mulch. Sometimes in urban neighborhoods, it’s hard to convince ourselves and our neighbors to use ordinary ground up plant materials instead of uniform bark nuggets. The best mulch is the plants own leaves and twigs, but any kind of mulch is better than nothing, so just do what works for you. Rock and gravel are also considered mulch with many of the same benefits as organic products.
If the month is on the dry side, remember to deep water your trees and large shrubs, even if they have lost their leaves. Your irrigation controller should be adjusted downward even if we don’t get a lot of rain. Cooler nights and shorter days mean that most plants will not need as much water, and water-logged roots and drowned micro-organisms could be a problem you won’t see until next year when the plants try to start growing again. If you have a water budget feature on your controller, November can mean fifty or forty percent of July. If you have a smart sensor controller, it may be doing this adjustment for you, but if you’re not sure, find out so you aren’t wasting water and harming the garden. Too much water also contributes to soil loss from erosion.
Stop dead heading roses and other spring-bloomers to encourage them to settle into dormancy. All plants require a dormant period to thrive into old age. Some of our native plants go dormant in summer. We are more familiar with plants like deciduous trees and roses that go dormant in winter. Don’t fertilize or try to keep them going too long. It is their season to wind down in preparation of a winter rest.
If you haven’t already, harvest winter squash and pumpkins. Set them in a cool dry place to cure for a week or two and then they will last all winter and sometimes if stored well, into next year.
CONSERVING: If you have non-native milkweed, usually with orange or yellow flowers, make sure the flowers are pruned off by now to encourage Monarchs to migrate. The cold of winter will kill the butterflies if they stick around. Or consider replacing that non-native variety with a California species. Narrow Leaf Milkweed (Asclepias fascicularis) is the easiest both to find now in nurseries and to grow in a normal garden setting. You can check and refill bird feeders with fresh seed and check after rainstorms to make sure the seed isn’t moldy. Consider leaving some seed stalks on some of your grasses and perennials for birds to forage this winter. Many bumblebees over winter underneath ornamental grass so be cautious if you must trim them now.
In the edible garden, add straw, old hay, alfalfa pellets and/or compost to the planting beds. If you take care of the soil, your plants will be stronger and better able to resist pest pressures next spring, making it possible to save time and money and reduce the need for synthetic chemicals. Keep after the weeds that use up nutrients. It’s too late to solarize soil, but you can cover with weed cloth or other fabric that allows air and water exchange until spring.
Happy harvest! Happy (hopefully) rain and snow month!