Understanding Garden Zones

An important part of learning to garden is understanding your gardening zone.  Your gardening zone can help you determine the right time to plant certain vegetables, what plants will flourish in your climate, and help you understand how your climate might differ from other gardeners you meet.

My gardening zone is zone 10b. The “zones” are determined by the average minimum temperatures in an area and are organized by the USDA Plant Hardiness map. For instance, my minimum temperature gets in the range of 35 to 40 degrees Fahrenheit—that is the coldest we get on average at any point in the year. Another example, if you live in zone 9a, your minimum average temperature could be anywhere between 20 to 25 degrees Fahrenheit.

What is my gardening zone?

If you have not looked up your gardening zone yet, simply click here to be directed to the USDA zipcode lookup page. On that site, you can type your zipcode into the lookup box and it will tell you what your USDA Planting Zone (aka hardiness zone or gardening zone) is. So, now that you’ve answered ‘what is my gardening zone’ I’d like to share how you can use this information to help you be a better gardener!

But what are sunset zones?

The gardening zones I am referring to in this article are set by the USDA plant hardiness map and are a very basic understanding of general climates. There is another system called the “Sunset Climate Zones” that a lot of Western gardeners refer to. Created by Sunset Magazine, this zone system factors in more than simply average minimum temperatures. The sunset zones take into consideration summer highs, rainfall, and humidity. In many ways this system is more detailed, as the USDA gardening zones do have flaws, but at this time the USDA gardening zones are used most widely in the gardening community and by plant companies.  Therefore, for most garden references nationwide and on plant tags, the USDA gardening zone is the one to refer to, but if you are curious what your Sunset Climate Zone is click HERE.

What does your garden zone tell you?

Once you know your garden zone, you can use that information to create a successful garden. Here are some ways to use your garden zone to help you garden more succesfully:

♦Find local gardeners or gardeners who are in your same zone. Ask them what they are currently growing. What kinds of vegetables do well in their gardens. Ask them their favorite tips for starting a garden in your zone.

♦Use the internet to look up planting schedules for your zone. I should note, some websites publish planting schedules that are generic and are not based on actual experiences. For example, there are some zone 10b schedules out there that my personal gardening experience did not agree with—so that’s why I refer you back to my first point. When it comes to gardening, experience is the best teacher!

♦Make smart plant purchases! Before purchasing a plant, look up what zones are ideal for that plant (or check the label). If your zone is listed, then there is a good chance that plant will do well for you.

Being in zone 10b, with an average low temperature between 35-40 degrees, means that my seasons are essentially divided into two groups: vegetables for growing between 40 to 70 degrees F (hence cool season), and vegetables for growing between 70 to 90 degrees F (warm season). Of course, we have some days that reach over 100 degrees. During unusual temperature spikes, I try and shade whatever vegetables I can and continue with good, deep watering. On average, these are not norms for my area so I don’t consider it a different season. Same with frosts. Last year we only had a handful of days lower than 35 degrees, so I covered whatever plants I could and hoped for the best.

Are you a zone 10 Gardener? Get a FREE Seed Planting Schedule

More specifically, are you gardening with me in zone 10b, Orange County, Los Angeles County, or San Diego County? If so, I’d like to let you know about my Current Southern California Seed Schedule. Every year I record my planting times and observations in order to learn more about how to grow successfully in my climate. Some things—like peas, cauliflower, and calendula—don’t perform as well when planted at the same time as most other garden zones. My Current Southern California Seed Schedule is available to all subscribers, and you might find it helpful as a starting point in your gardening journey as well! You can subscribe in the box above.

California gardeners might also find my series on creating a CA native plant garden useful. I’ve recently added a new DIY pollinator sitting area that not only thrives on very little water, but also contains CA native plants that attract hummingbirds, bees, butterflies, and more!

Let’s Talk Microclimates

Now that you know your gardening zone, it’s also important to talk about microclimates. Did you know that someone just a mile away can have a completely different microclimate than you? Microclimates are the unique characteristics of your specific area within the larger, general climate zone. Microclimates are effected by things like mountains, rivers, oceans, hills etc. For example, some of my fellow zone 10b gardeners are located closer to the beach. They tend to have less severe temperature swings than I do throughout the year. It can take many seasons for you to finally get comfortable with your unique microclimate, and there is no shame in that. In fact, one of my favorite pieces of advice to give new gardeners is to ask local garden friends what they grow successfully. There’s a pretty good chance that those same varieties will fare well in your garden as well. Fun Fact: Did you know your garden can have its own microclimates within itself? Structures or features within your own yard can create microclimates (such as extra large trees, decks, water features, etc.)

Find your Last Frost Date

It’s always useful to know the average date of the last frost in your area. Why? If you look at the instructions on seed packets you’ll often see the words “sow indoors __ weeks before your last frost date.” These instructions are meant to help you know when to start your seeds so you can have plants ready for Spring transplanting. See below for the Old Farmer’s Alamanac Frost Dates link. The information there is based on averages from 1981-2010, so I like to add two more weeks just to make sure I am out of any frost danger. Always keep up on your local weather!  https://www.almanac.com/gardening/frostdates

Get Gardening!

Alright, now that you are armed with all this information, you are well on your way to creating a successful garden! Here are some other gardening articles you might find interesting:

What Type of Garden is Right For You?

Seed Starting Articles

Where I Buy Seeds

Compost Tumbler Basics

How to Amend Your Soil Organically

Organic Pest Control Articles