Sunset areas

Question from James:
The Sunset Western lists our San Diego area as between 14 & 24 but I find many products require a more specific zone. I thought that if I provided you with a more detailed location, you could provide me with a closer zone. We live at the top of the hill above the Costco store on Morena Blvd – literally at the top of the hill. Our house overlooks the canyon just to the north of Jutland Drive. If there is any wind, we get it coming over the crest. The property faces due West and we get full sun all day in Carol’s large garden. In future times, I plan to get into berry bushes (black, boysen, ras, etc) and fruit trees but many of the references state they won’t grow well here. Some catalogs refer to a specific zone within the 14-24 range and I don’t know if they will grow on our plot. If you could give me a closer zone number, it will be most helpful. Carol likes your site and I’ll try to visit some more. Many thanks.

Answer from Pat:
Your home and garden is in Sunset Zone 23, the largely frost-free zone that is right next to the coastal fog zone, Zone 24. Though I have often seen fog lick the hillside where you live your home and garden are not right on the edge of the ocean. The narrow strip along the ocean is Zone 24 and the next zone inward is Zone 23 which is where you reside. See page 53 in Sunset Western Garden Book for a description of Zone 23.

Los Angeles differs from San Diego in that Zone 22 is next to Zone 24 in Los Angeles. This is because of the LA Basin, a geological formation we do not have here. Zone 22 is slightly more extreme than Zone 23 where you live. Thus our climate here is more subtropical than LA and we have a milder climate in which we can grow a wide range of tropical and subtropical plants without fear of frost. On the other hand a little frost and winter chill enables one to grow a wide range of plants that need winter chill. For example, grape hyacinth bulbs come back into bloom in the Los Angeles Basin every year but that is not true of the coastal zones in San Diego. You have to live inland to have grape hyacinths naturalize in your garden.

National catalogues do not use the Sunset Zones. National catalogues use the USDA climate zones and they have no reference to growing conditions here since they are not precise enough. They are all wrong for here. For example using the USDA zones you would think an azalea could survive in Phoenix, Arizona and that is ridiculous.

Rabbiteye blueberries will grow fine in your zone. A plant such as gardenia won’t bloom in Zone 24 because of a lack of the spread of temperatures a gardenia has to have in order to bloom. Also, oranges in Zone 24 often fail to have the sweet-tart flavor one desires, but in your zone almost any plant that is recommended for a mild Mediterranean climate will thrive, including citrus and gardenias, so I can’t quite understand the problem that is bothering you. I think your main problem is that you are looking at catalogues of fruit trees and berries that are not adapted to our climate.

Please purchase a copy of Sunset Western Garden Book and look up the low-chill fruit variety lists for berries and trees that you will find in that book. Only plant and grow varieties adapted to low-chill conditions. Grow the varieties that are adapted to your climate and not to a cold-winter climate.

Another way to learn what grows well in your climate zone is just to observe what other good gardeners are growing. Whatever is doing well for others will do well for you.

However, there are not too many good gardeners that I have seen close to you. One of the most important things to do on a mesa top is to build up the soil with organics. Many of the gardens on the top of that hill could use a lot more organic compost, manure, seaweed, humic acid, and other organic soil amendments than they are getting and they could also do with a good layer of mulch on top of the ground. Healthy soil makes for healthy plants.

Here is a P.S. to your question: Many raspberry and blackberry varieties thrive in your climate zone. Look for plants in local nurseries instead of in catalogues. Or look at the lists of varieties in Sunset and then look them up on the Internet to find where you can purchase them. Oregon 1020 is a good raspberry and ‘Bababerry’ is a good one too. ‘Brandywine’ , which has large purple berries works also. There are so many good blackberries you can grow I can’t list them all, but ‘Black Satin’, ‘Boysen’, ‘Ollalie berry” and ‘Dirkson’ are just a few of the many from which you can choose. Caterpillars are the main problem with cane berries. Floating row covers can keep off cabbage butterflies and birds too. Or treat with Spinosad, but protect your bees. Spinosad kills bees!