Planting Perennials in the Fall

Gardener’s Notebook by Joshua Burman Thayer

Each year in February, I sprout out a bunch of summer crops like corn, squash, cucumber, tomato, and peppers. In about 10 weeks, they are large enough to sell to my home garden clients who are planning their summer gardens. In 2020, instead of selling my sprouts, I decided to give “seed gardens” as gifts to a dozen beloved households. Every single one of the 12 took the time, care, and energy to foster a bountiful summer garden. Indeed, if there is a silver lining to these troubled times, it may be the renewed focus on food growing.

If you are looking ahead to your summer 2021 vegetable garden, consider starting a multistoried food forest to utilize your vertical space with perennial fruit trees growing above your annual food crops. By integrating annuals and perennials, you mimic nature and provide the conditions for a thriving, diverse home garden.

Autumn is the Time to Plant Evergreen Perennials

In August, when long, hot days can bake everything into oblivion, it’s best to avoid planting delicate young plants. Autumn brings shorter days, cooler evenings, and diminished solar pressure, making this a good time to plant. Generally, deciduous plants—those that lose their leaves each winter—are best put in the ground in winter or spring. Conversely, evergreen plants—those that do not lose all their leaves at once—should be put in the ground now, when cooler temperatures give them stress-free time to acclimate.


Plant high on a mound before and after covering with soil. (Photos by Joshua Burman Thayer)


The following evergreen perennial edibles are good choices for your Bay Area home garden:

Rich in protein, avocado (Persea americana) is an affirmation of community food support. Imagine harvesting hundreds of tasty avocados from your own yard and sharing with others. Avocado trees tolerate mixed light or full sun. They prefer to sit in a 1-foot-tall tall planting mound (see photo above) with 10 feet of spacing all around to allow for growth toward maturity. The popular Haas and Bacon cultivars need rich, well-drained soils.

Did you know that an olive tree (Olea Europaea) can live for 2,000 years? This ancient, wise plant has offered humanity so much support with food, fat, and light. The trees love most parts of sunny California and should be planted in full-sun locations with 10 feet of space all around them. Since the olive tree loves rocky soil, put it in a 1-foot-tall tall planting mound and add gravel into the hole. Try Mission and Mauro cultivars.

The gorgeous pineapple guava (Feijoa sellowiana) yields up both edible fruits and flowers, and its tolerance of diversity in soil and light makes it a versatile option for your East Bay garden. Plant in a dry part of the garden or adjacent to a lawn. With ample water and fertilizer, it will grow quite fast. Try Nazemetz and Moore cultivars.

Carob (Ceratonia siliqua) is a rugged plant that provides protein for humans (and goats!) in the driest and sunniest parts of the Bay Area. A natural nitrogen fixer, it improves and builds the soil around it over time. Plant in full sun in rocky soil on a 1-foot mound for good wet-season drainage. Try the Colombia cultivar.


Lay down cardboard as your first mulch layer and then cover it with a layer of organic mulch.


Add Some California Native Evergreen Perennials

As you build your food forest, consider adding these natives under your food-producing trees. Each brings myriad benefits:

Wax myrtle (Myrica californica) provides good bird habitat.

A rugged full-sun native, manzanita (Arctostaphylos spp.) adds geometric texture to the garden.

Each spring, native plant lovers look forward to the lovely blue flowers of ceanothus (Ceanothus spp.). The shrub is also a great soil builder.

Coyote bush (Baccharis pilularis) provides a winter source of nectar that’s an important part of your local ecology.


Another Chance for Catch Crops

Once you have added all your new perennial evergreens into the fall garden, consider planting some catch crops around tree bases.

This Gardener’s Notebook is one of Joshua Burman Thayer’s monthly columns for this newsletter, East Bay Appetizer. He also contributes longer articles for Edible East Bay’s print magazine, all archived at Check out his design site: