USDA Zone 9: Where is it? What to Plant? Tips to Success
For people who are looking to establish a home garden, understanding what growing zone your property falls under is important.
Summer in zone 9 is long and hot, whereas winters are mild and warm compared to cooler zones. The growing season in zone 9 is exceptionally long, so there are plenty of trees, vegetables, flowers, and other plants that will grow well in these regions.
Let’s take a closer look at zone 9, as well as the average frost dates and growing options for gardeners who live in it.
What is Zone 9?
Zone 9 is one of 13 plant hardiness zones set out by the United States Department of Agriculture and their USDA Plant Hardiness Map. These climate zones are used to indicate the minimum average winter temperatures in every region of the United States, including Alaska, Hawaii, and Puerto Rico.
Each zone runs largely latitudinally across the country, with each one being warmer (south) and cooler (north) than the zones adjacent to them.
With at least 9 months between frost dates, Zone 9 has an exceptionally long growing season with early spring planting and a long fall, so gardeners in zone 9 are fortunate to be able to garden all year round. This includes winter too since the coldest months are mild enough that some cool-weather crops can still thrive.
What’s more, the excellent climate means that most varieties of vegetables and herbs can be planted successfully in these regions.
In Tucson, Arizona, which falls under zone 9a and 9b, summer temperatures can creep as high as 99.7 degrees F in July.
This zone is mostly found in the pacific northwest, along the west coast, and through the lower third of the southernmost states.
Where is Zone 9?
Zone 9 is less present than the zones before it, mostly relegated to the west coast and through some southern states.
It first appears in the pacific northwest, along the coasts and inlets in Washington, moving down to take up significant portions of the coast in Oregon and California, parts of Nevada and Utah, and approximately half of Arizona.
It then moves through many of the southern states of the US, appearing sparsely in New Mexico, in the southern thirds of Texas and Louisiana, the central portion of Florida, and small southern pockets of Mississippi, Alabama, Georgia, and South Carolina.
It also appears sparsely in small pockets of inland Hawaii.
Minimum Average Temperatures in Zone 9
In simple terms, USDA growing zones are defined by minimum average temperatures. So whichever zone you are in will tell you approximately how low the winter temperatures will be, within a range of 10 degrees.
Each zone is further split into subzones A and B, which are separated by 5 degrees F.
- Zone 9: covers minimum average temperatures of 20 to 30 degrees F.
- Zone 9a: this subzone covers minimum average temperatures spanning from 20 to 25 degrees F.
- Zone 9b: this subzone covers minimum average temperatures spanning from 25 to 30 degrees F.
Of course, the minimum average temperature ranges are only a guide, not a rule. These temperatures can fall below or above these ranges in any given year, especially during periods when unexpected weather patterns occur.
Frost Dates in Zone 9
Frost dates are another important aspect of USDA growing zones that people need to understand when preparing their home garden. The first and last frost dates tell you when to begin and end your planting through the year, as most crops will not survive the frost.
- Last frost dates: February 6th – February 28th
- First frost dates: November 25th – December 13th
But like minimum average temperatures, frost dates should be viewed as guidelines. Unpredictable weather and seasonal changes can result in fluctuating frost dates that can end weeks earlier or later than expected.
Zone 9 States
Most USDA zones can be found in various states throughout the US. But every state (with the exception of Delaware) falls under multiple USDA zones as well. Minimum average temperatures can vary widely from one side of a state to the other – for example, California falls under zone 5a all the way to zone 11a and Louisiana falls under zone 8a to zone 10a.
These are the states that fall under zone 9:
- New Mexico
- South Carolina
Zone 9 appears in 15 states altogether, though it is much more prevalent running along some southern parts of the country and the west coast. It is most prevalent of all in states like California, Arizona, Texas, and Florida. In states like New Mexico, Mississippi, and Alabama it only appears in small areas in the southern parts of these states.
If you want to know which zone you are gardening in, simply enter your zip code into our interactive hardiness zone map.
When to Plant in Zone 9
Planting cool and warm-season crops will typically take place after the last frosts have passed fully, so in zone 9, this will be from early March onward.
Of course, many crops will be planted at different times depending on their requirements, as some will need warmer soil before seeds can germinate and the plants can reach harvest. Frost dates may also fluctuate, allowing you to plant seeds outdoors earlier or forcing you to plant later. Tracking local weather patterns will give you a more specific idea of when to plant.
While the last frosts end in March, zone 9 winters are warm enough that you will be able to sow cold-weather crops like broccoli, cauliflower, cabbage, lettuce, etc outdoors in January and February before the last frost dates. Granted, they will need winter protection such as a grow tunnel or protective fabric.
Warm-weather crops such as kale, peppers, tomatoes, squash, etc can be planted indoors in January and moved outdoors in March and April. From April onward, all warm-weather vegetables can be planted outdoors up until the first frost dates set in.
Because zone 9’s growing season is over 9 months long, it is considered a “year-round” growing season. Most vegetables have plenty of time to germinate and reach harvest and can be planted twice a year to maximize yield.
Tips for Gardening in Zone 9
Understanding which USDA hardiness zone you live in will give you an idea of the temperature ranges you can expect in winter, and when you can begin and end your annual planting. But there is plenty more that you should know if you’re going to get the most out of your zone 9 garden.
- Check all of your seed packets for further gardening information, such as maturation dates (when your plants reach harvest time), when exactly you should begin planting, soil temperature requirements, and whether you should sow seeds indoors first.
- The zone 9 climate is hot, particularly in summer, so make sure to take precautions for cool-weather crops, as even the shoulder seasons may prove too hot for them. Shade cloth, mulching, and tactical planting for natural shade are just a few ways you can protect your plants from extreme heat and sunshine.
- When it comes to planting trees, shrubs, and perennial flowers, consider tropical plants with low water requirements, as these are the ones that will thrive more easily and with the least maintenance in the hot zone for 9 summers.
- Keep a close eye on weather forecasts, as this will give you time to prepare your heat protection and shade in advance, as well as provide the nutrients your plants need ahead of time.
Choosing Plants for Zone 9
While gardeners in zone 9 typically do not have to worry about the cold hardiness of plants and trees, they have their own unique environmental challenges. With exceptionally long summers and warm winters and shoulder seasons, hot weather needs to be taken into consideration when choosing plants for your zone 9 garden.
But the first and most obvious place to begin is the local plant nurseries and garden centers in your area. In these locations, you should find a broad range of plants and trees that grow best in your region. Employees also tend to have niche knowledge of local gardening and can answer some of the gardening questions you might have.
Seed companies should also provide extra zone information and temperature requirements on their seedling packets and websites.
Consider asking local friends and/or family members who keep a garden, or anyone else who may have expert knowledge on local gardening. These people will be an excellent source of information for things like local weather patterns and microclimates.
If you are a beginner gardener you can make things easier for yourself by choosing hardy and adaptable natives, and even favoring perennials that only need to be planted once and will die off and reappear after the frosts have passed.
What to Grow in Zone 9
Now that you understand the temperature ranges, frost dates, and broad gardening schedules of zone 9, it’s time to choose the trees, vegetables, herbs, and flowers you want to grow.
Fortunately, due to the 9-month growing season and potentially year-round gardening potential, gardeners in zone 9 have a healthy variety of plants to choose from.
Trees for Zone 9
Growing abundant fruit trees in your own backyard can be immensely rewarding. If you want to plant some of your favorite fruit varieties in zone 9, consider these types.
- Avocado trees: While many see these creamy fruits as a savory ingredient, avocados also do well in smoothies and desserts, and are packed with healthy fats and vitamins. Avocado trees typically prefer warmer, more subtropical environments, but there are various “cold-hardy” avocado varieties that will thrive in zone 9. In particular, Mexican and Guatemalan varieties do well here, including the Fuerte, Stewart, Mexicola, Hass, Reed, and Bacon. Avocado trees will need plenty of space, well-draining soil, and atleast six hours of direct sunlight per day.
- Starfruit trees: A unique and eye-catching option, starfruit trees bear juicy yellow fruits that are sweet and tangy, and are often grown for their ornamental value as well as their produce. Their pink and purple blossoms grow abundantly in summer. Starfruits thrive in zones 9 to 11, and while plenty of varieties can be grown in zone 9, if you are worried about frost temperatures you can always grow dwarf varieties in containers to be moved inside in winter.
- Peach trees: While peach trees grow best in zones 6 to 8, there are several varieties that do well in zone 9. These stone fruits can be made into jellies, jams, desserts, or eaten fresh, and their trees produce pink spring blossoms that add color and texture to your landscape. Peach trees can take three or four years to fruit, so young trees are a good option if you want to harvest peaches soon after planting. Because peach trees cannot always tolerate high heat, varieties like the Suncrest and O’Henry are a safer bet in zone 9.
- Other fruit trees: Nectarines such as the Sun Grand, Silver Lode, Desert Delight, Warren, and Harrow Delight pears, Santa Rosa and Burgundy Japanese plums, Hardy Red and Issai kiwi, figs such as the Chicago Hardy, English Brown Turkey, and Celeste, Meyer lemon, Akane and Pink Lady apples, and apricots such as the Tilton, Golden Amber, and Flora Gold.
Flowering trees offer beauty, color, and texture to any garden during summer and/or spring. Plenty of tropical and subtropical flowering trees do well in zone 9 temperatures.
- Chitalpa: The chitalpa tree is an attractive hybrid, crossed between a southern catalpa and a desert willow. They grow up to 30 feet tall on average and bear clusters of pink blossoms (very similar to catalpa blossoms, but smaller) through spring and summer. The important thing to look out for when maintaining a chitalpa is insect infestations, such as aphids. Insects can negatively affect the health of the tree and cause leaves to drop. Otherwise, it is relatively low-maintenance, fast-growing, and drought resistant.
- Jacaranda: These gorgeous tropical trees erupt into purple blooms in spring and summer, their branches almost entirely covered in flowers. They make a beautiful and striking addition to any landscape, and their wide, branching canopy makes them a useful shade tree too. Jacaranda’s will not thrive in temperatures below 15 degrees F, and they are better suited to 9b over 9a. Zone 9 gardeners based in Hawaii should note that the jacaranda is an invasive species in this state. In the continental US, they grow best in Texas, Florida, and California.
- Royal Poinciana: The royal poinciana is an evergreen African native that will draw the eye no matter where you plant it. Also named “flame tree” for its unique, blazing red and orange flowers, the poinciana’s flower clusters, dense foliage, and spreading canopy provide summer shade and winter insulation. They are also exceptionally fast growers, shooting up to 5 feet each year, though they typically take 6 to 10 years to bloom.
- Other flowering trees: Oakleaf Hydrangea, Fashion Azalea, Crape Myrtle, Red Dogwood, Wisteria, Mimosa, Bottlebrush, Southern Magnolia, Sweetbay Magnolia, Star Magnolia, Saucer Magnolia, Bigleaf Magnolia, Eastern Redbud, Althea, Pink Dogwood, White Dogwood, Forest Pansy Redbud, Horse Chestnut, Chitalpa, Goldenrain Tree, Desert Willow, Chaste Tree, Angel Trumpet, Sweet Acacia,
Your winter landscape does not have to be cold and colorless. With the right evergreen trees, you can enjoy bright and eye-catching scenery every season.
- Deodar Cedar: This evergreen conifer is native to Asia, in particular the Indian subcontinent, and is even considered a sacred tree in the Hindu religion. It has a graceful ‘weeping’ growth habit and pyramidal form and fine, textured blue-green needles that grow in clusters. It can reach up to 70 feet in height and is often grown as screening or windbreaks in hot climates. It is particularly tolerant of heat, wind, and drought.
- Tea Olive: Known for their delicate white flowers that fill the air with a deliciously sweet and fragrant scent, the tea olive can bloom twice – first in spring, and again to a lesser extent in fall. This makes it an appealing addition to a garden that may lack color and fragrance in the fall. Grown as a shrub or small tree, the tea olive is hardy and adaptable, resistant to disease, and only requires occasional pruning to maintain its height and shape.
- Waxleaf Privet: Perfect as an adaptable hedge, the glossy-leaved waxleaf privet grows quickly and is easily pruned into whatever shape you prefer. Its small and fragrant spring blossoms add softness and beauty to the landscape and along with the plant’s dark berries, it also attracts local pollinators, including various birds and butterflies. Reaching up to 10 feet, they can be grown as a privacy fence or windbreak. The waxleaf privet is resistant to pests and disease and tolerant to drought and salt.
- Other evergreen trees: Loblolly Pine, Leyland Cypress, Italian Cypress, False Cypress, Eastern Juniper, Mexican Fan Palm, Pygmy Date Palm, Sylvester Palm, Japanese Black Pine, Bald Cypress Tree, Spartan Juniper, Hollywood Juniper, Wichita Blue Juniper, Coastal White Cedar, American Holly, Oak Leaf Holly, Robin Red Holly
Native trees are an excellent addition to any landscape – they tend to take to the local climate and soil very well, and are typically hardy and low-maintenance.
- Sweet Acacia: Sweet acacia is not a common tree in landscape gardening, but this small to medium-sized native is a rewarding option for more experienced gardeners. Its stems are covered in silvery spines, which can make maintenance difficult, but in late winter-early spring, its branches bear unique flowers that look like yellow puffballs. They attract pollinators and give off a lovely scent that is even used in perfume-making. It is a hardy, durable tree that thrives in dry desert landscapes.
- Bigleaf Maple: A highly abundant hardwood species in the Pacific Northwest, the bigleaf is a deciduous native maple that can grow up to 100 feet high and live as long as 300 years. They have the largest leaves of any maple species, growing approximately 12 inches across, according to the US National Park Service. Those same leaves transition to a lovely yellow and orange in fall. Be careful when planting bigleaf maple, as their roots can interfere with plumbing and infrastructure, and even burst through cement.
- Desert Willow: Unique and eye-catching, the desert willow is a colorful shrub growing natively in the southwest of the US. It is small and delicate, typically only reaching 20 feet tall. Its pink and violet trumpet-shaped flowers, drooping leaves, thin branches, and uneven growth habit will add a graceful and somewhat quirky charm to your zone 9 property. The desert willow grows easily and needs very little care and maintenance once it is established.
- Other native trees: Brazilian Bluewood, Bodark, Desert Willow, Black Hickory, American Holly, Bigtooth Maple, Mescalbean, Mexican White Oak, Longleaf Pine, Sassafras, Carolina Buckthorn, Black Walnut, Black Maple, Mexican Ash, Pecan, Bald Cypress, White Dogwood, Sweetbay Magnolia, Red Maple, Eastern Redcedar, Hazel Alder, Florida Maple, Sweetgum, Spruce Pine, Winged Sumac, Water Oak, Eastern Cottonwood, Green Ash, Bigleaf Magnolia, Pignut Hickory, American Hornbeam
Vegetables for Zone 9
With its long summers, warm fall, and very mild winters, zone 9 has a practically year-round growing season that is well-suited to the majority of vegetables.
- Kohlrabi: These somewhat unique cruciferous vegetables have an edible bulb that goes well roasted or in soups. While Kohlrabi grows best in cooler temperatures and has a tendency to bolt when the soil warms up, it can still be grown in zone 9 and even zone 10. They can be started indoors or sowed directly outdoors from mid-fall, in September, to early spring in March. It takes 45 to 60 days to reach harvest and planting should be timed accordingly so they mature before the soil reaches 75 degrees F.
- Green Beans: In zone 9 green beans can be planted straight into the ground starting from March, and do best in soil temperatures that are between 70 and 80 degrees F. Though they grow well in zone 9, consider adding an inch of loose mulch when planting green beans outdoors to keep the soil cool. When choosing green beans to plant you should research wisely, as there are many varieties and some will do better in your specific climate than others.
- Pumpkins: The most iconic of the winter squashes, the pumpkin is a warm-weather vegetable that needs soil temperatures of 60 degrees F or higher before its seeds will germinate. Pumpkin planting in zone 9 can begin in March. They can take anywhere from 75 to 100 days to grow from seed to harvest, so with the right timing, you can plant pumpkins twice a year. They are intolerant to frost, so make sure the last frost has passed completely before planting.
- Other vegetables: Peas, beets, cauliflower, broccoli, cucumbers, eggplants, tomatoes, peppers, endives, collard greens, kale, leeks, onions, radishes, turnips, carrots, celery, beans, kohlrabi, lettuce, okra, pumpkins, summer squash, corn, sweet potatoes, cabbage, asparagus
Perennial Flowers for Zone 9
Nothing brightens up a home garden or landscape more than perennial flowers. Here are some of the most beautiful perennial flower varieties that thrive in zone 9.
- Nasturtium: The colors of the nasturtium are rich and bright, adding intense splashes of orange and yellow to your garden. Not only are their flowers and large circular green leaves beautiful to look at, but the plant itself has a variety of uses. Everything from the flowers and leaves to the seedpods is edible, and they can also be planted around vegetable beds to act as an aphid trap. There are plenty of varieties too, so you can grow them as bushy plants, climbers, ground cover, etc.
- Bulbine: Native to South Africa, these colorful perennials bear small yellow and orange star-shaped flowers, and in the US have taken off in popularity in recent decades. Their foliage looks similar to grass, and the flowers grow on thin stalks that are approximately a foot high. The bulbine is a particularly low-maintenance flower, able to thrive in poor soil and dry conditions, making them a good choice for rock gardens. They also make a good choice as an accent plant for herb gardens and flower beds.
- Mexican Petunia: Though the Mexican Petunia is not strictly a petunia, its bright purple flowers look very similar, and are similarly eye-catching. Due to their heat tolerance, they are an excellent choice for southern states, and their flowers bloom in succession from spring to fall. It attracts plenty of pollinators and can grow up to 3 feet tall. Mexican Petunia is a fast-growing self-seeder, so make sure to check whether this plant is invasive in your state. For example, it is considered highly invasive in Florida, according to the University of Florida Gardening Solutions.
- Other perennial flowers: Blue Salvia, Tropical Milkweed, Sage Tree, Blanket Flower, Lantana, Butterfly Weed, Butterfly Bush, Wax Mallow, Black-Eyed Susan, Daylily, Sedum, Hosta, Asiatic Lily, Liatris, Trumpet Vine, Lemmon’s Marigold, Pavonia, Shasta Daisy, Firecracker Plant, Mexican Petunia, Crepe Myrtle, Rock Rose, Chinese Fringe Flower, Golden Dewdrop, Siberian Iris, Tiger Flowers, Yarrow
Herbs for Zone 9
Herbs are an excellent accessory to your zone 9 vegetable garden, as they tend to grow easily and can be annual, biannual, and perennial, as well as adding plenty of flavor to your home-cooked meals.
- Cilantro: able to grow in a wide range of climates, from zones 2 to 12, cilantro (also known as coriander) is both a polarizing and immensely popular and useful culinary herb. It is prized in cuisines around the world, from Mexico to the Middle East to India. It is a fast-growing herb that can be grown in spring and fall, and its leaves can be harvested after just 30 days. It should be grown in temperatures between 50 and 80 degrees F.
- Tarragon: A popular perennial European herb, tarragon comes in two varieties – French, which is most often sold and used commercially, and Russian, which is less flavorful. These plants can reach up to 3 feet in height and should be harvested and pruned regularly to prevent flowering. Tarragon cannot be grown from seed, and instead must be transplanted from cuttings. It will wither in high heat and sun, so some shade and heat protection may be useful in zone 9.
- Peppermint: A hybrid between spearmint and watermint, peppermint is a sweet, slightly spicy-smelling herb that can be used for various medicinal purposes and turned into tea, oil, and extracts. It is less invasive than most mint species, but still has a tendency to spread beyond its growing areas. Peppermint is best grown between 50 and 75 degrees F. Keeping the soil consistently moist will help protect it from dry, hot conditions.
- Other herbs: parsley, basil, chives, cilantro, oregano, parsley, catnip, mint, rosemary, fennel, licorice, marjoram, lemon verbena, lavender, dill, licorice, sage
The Zone is Only Part of the Story
Getting acquainted with the USDA hardiness zone that you live in is an important part of understanding what plants can grow on your property, and when you can plant them. But it’s only the beginning – so much goes into establishing a vibrant landscape garden, and there is plenty more to learn.
Understanding the unique weather patterns, microclimates, and soil types in your area, and familiarizing yourself with the growing requirements of the plants you wish to grow, are equally important.
Now that you’ve learned more about zone 9, its frost dates, and minimum average temperatures, these are the next contributing factors to understand before you get to work. But once you understand the basics, you’ll have a beautiful zone 9 garden in no time.