For some US gardeners living in the south of the country, their property will fall under USDA hardiness zone 10. This zone is characterized by long, hot summers, mild winters, and warm shoulder seasons.
Zone 10 covers areas with some of the warmest temperatures in the country, so there is plenty that proactive gardeners should know if they want their gardens and landscape plants to survive and thrive. Let’s take a look at what defines zone 10, and what it means for gardeners in these regions.
What is Zone 10?
Zone 10 is one of 13 zones defined by the US Department of Agriculture Plant Hardiness Zone map. These zones are differentiated by their minimum average temperatures in winter, which help US gardeners to understand which plants will or will not grow in these regions.
These USDA hardiness zones, also known as growing zones, cover the entirety of the continental United States, Hawaii and Puerto Rico. They run latitudinally through the contiguous US, starting from the top (zones 3–5) to the bottom of the US (zones 10-11). Zones 1 and 2 are only found in Alaska and Zones 12 and 13 are found in Hawaii. The lower the zone number is, the lower the minimum average temperatures will be.
So it should be no surprise that zone 10 encompasses some of the hottest areas of the country. Unlike lower growing zones where the cold hardiness of certain plants needs to be taken into account, plants and trees in zone 10 will need to be able to tolerate the sometimes intensely high temperatures during the hottest parts of the year.
The growing season in this zone spans from January to December, giving zone 10 gardeners the ability to plant at any time of year, depending on the type of plants.
Where is Zone 10?
This zone begins in small pockets of the central west coast of California, picking up again in Southern California.
It also appears in the southernmost parts of Nevada, and the southwestern parts of Arizona. Further down it can be found in the south of the country, in southern Texas, southeastern Louisiana, and the southern quarter of Florida.
Zone 10 can also be found in inland Hawaii, particularly on the Big Island, Maui, and Kauai.
For the most part, with the exception of Florida and Hawaii, zone 10 is found in sparse, scattered areas of these states.
Minimum Average Temperatures in Zone 10
Each zone is defined by its minimum average temperatures, and zone 10 winter temperatures are some of the hottest in the continental US.
Growing zones are also separated into two subzones: 10A and 10B. Both are separated by five degrees F, with zone 10A being the cooler of the two.
- Zone 10: covers minimum average temperature spanning from 30 to 40 degrees F.
- Zone 10a: this subzone covers minimum average temperature spanning from 30 to 35 degrees F.
- Zone 10b: this subzone covers minimum average temperature spanning from 35 to 40 degrees F.
But these minimum average temperatures are only a guideline – weather patterns can be unpredictable, so they can drop to lower or rise to higher temperatures from year to year.
Frost Dates in Zone 10
Frost dates tell us when we can expect the first and last frosts of the year to occur. This will indicate to gardeners in respective zones when to start planting trees and crops, and when to cease planting.
For zone 10, the period between the first and last frost dates is very short, if a frost occurs at all.
- Zone 10 first frost dates: December 13th-December 31st
- Zone 10 last frost dates: January 15th – January 31st
Like minimum average temperatures, frost dates are not set in stone and are subject to fluctuate depending on annual weather patterns. This is particularly true in zone 10, where frost dates are rare and sometimes no frosts will occur at all.
Zone 10 States
Hardiness zones are found in several states, with the exception of zones 1 and 2 which only occur in Alaska. And all states, with the exception of Delaware, contain more than one zone.
The states covered by zone 10 include:
Zone 10 is a much less prominent zone compared to many of the lower zones, even zone 9 before it. It only appears in 7 US states, beginning halfway down the west coast and appearing in pockets around the south, in particular along the southern coast in Texas, Louisiana, and Florida. In zones like Texas, Louisiana, and Nevada, only subzone 10a appears.
If you’re unsure which zone or subzone your property falls under, simply enter your zip code into our interactive hardiness zone map.
When to Plant in Zone 10
Typically planting will begin when the last frost dates have passed, and the weather begins to warm up. However, in zone 10 and beyond the frost periods are so brief that you can usually plant through the entire year, though of course some plants and trees will require certain soil temperatures.
With over 10 months of warm weather, and sparse frosts (if any), cold-weather crops do not need to be started indoors. Vegetables like broccoli, spinach, onions, etc can be planted directly into the ground. They should be planted in fall and harvested by early spring, as many will not survive the sweltering summer conditions.
Zone 10 is often warm enough that warm-weather crops such as tomatoes, peppers, and eggplants can be planted from spring through summer, and possibly into fall depending on soil temperatures. Monitor the temperatures in your area diligently and you will find that there will be plenty to grow throughout the year, with enough time to plant and harvest some vegetables twice over.
Tips for Gardening in Zone 10
Understanding minimum average temperatures and frost dates will tell you when you’re able to start planting your trees, vegetables, and flowers. But once you are ready to start planting, these pointers will help you prepare to get the most out of your home garden.
- Check the water requirements of your chosen plants before purchasing them. There are often water restrictions in dry, arid areas that fall under zone 10 and above, and the last thing you want are plants you can’t water sufficiently.
- Humidity is another point to keep in mind. Areas in zone 10 tend to be hot and humid, and certain plants will not do well in high humidity.
- Prioritize soil preparation, as the soil in climates as hot as zone 10 is often poor-draining and nutrient deficient. Turning the soil and adding compost, or creating raised beds before planting are two ways of doing this.
- Heat protection will be one of the most important things to consider when you are planting and tending your chosen trees, herbs, vegetables, and flowers. Mulching, regular watering, and providing shade with shade cloth, sails, or even tactical planting near taller plants and trees, are all ways that you can protect your plants from heat stress.
- When purchasing seed, check your seed packet for extra information such as maturation dates, soil temperature requirements, watering requirements and more.
Choosing Plants for Zone 10
Choosing the right kinds of trees and plants is paramount to establishing a healthy and productive zone 10 garden. And while gardeners in cooler zones must contend with frost, rain, and wind, gardeners in zone 10 have very different factors to consider.
High temperatures that last for months, humidity, aridity, poor soil quality, etc, are just a few things you need to take into account depending on what part of the country you live in.
But there are many steps you can take to choose the right plants for zone 10. First, head to your local garden centres and plant nurseries, as they will stock a wide variety of trees and plants that grow well in your area. Any seed packets you buy should also provide useful supplemental information about the species you are interested in planting, and seed company websites may have additional info.
Reading regional gardening books and consulting locals with niche expertise will go a long way in helping you to familiarize yourself with local weather patterns and micro-climates that influence how your garden will grow.
Beginner gardeners will also benefit from choosing plants that are native and/or perennials. Natives tend to be hardy and very low maintenance, and perennials need only be planted once rather than replanting each year.
What to Grow in Zone 10
Now that you are more familiar with the zone 10 landscape and it’s minimum temperatures and approximate frost dates, let’s take a look at the impressive variety of trees, herbs, vegetables, and other plants that can be grown on your zone 10 property.
Though the high temperatures will be too much for some plants, there are still plenty of heat-tolerant species to choose from.
Trees for Zone 10
Even in the warmest regions, there are delicious fruit trees that will thrive and provide you with delicious produce. Here are some of the best fruit trees to grow in zone 10.
- Banana tree: Interestingly, the banana tree is not really a tree, but instead is the world’s largest perennial herb! With their thick woody stems and bright green palm-like leaves, banana “trees” add a tropical touch to your garden. Just remember to choose your species wisely – there are many varieties of banana trees and their sizes vary widely. Bananas need thorough and consistent watering from spring to fall, so be cautious if you live in an area with drought and/or water restrictions.
- Guava tree: Guavas are a relatively rare tree in the continental US, but are sometimes found growing in Florida, California, and Texas. These fruit trees are particularly sensitive and can be killed by even the shortest frost, so you should only plant them outdoors if you are confident that your regional temperatures can sustain them. Otherwise, guava trees provide plenty of visual appeal and their fruits are sweet and flavoursome. They like hot, moderately humid environments and can grow up to 20 feet tall.
- Lemon tree: The lemon tree takes 3 years to establish, and grows best in USDA zones 8-11. They are cold-sensitive trees that need protection from any frosts that may occur as well as plenty of sunlight and adequate water. They can be grown equally well in soil or in a container, though it’s unlikely they will need to be moved indoors in zone 10. Most lemon varieties will survive and thrive in zone 10, even the popular cold-hardy Meyer lemon.
- Other fruit trees: Glenn mango, Brown Turkey figs, Black Mission figs, Royal apricot, Muscadine grapes, Soursop, Persian lime, Surinam cherry, Loquat, Marina Strawberry, Papaya
- Flannel Bush: Native to California, the flannel bush is a beautiful flowering shrub or small tree that can only be grown in zones 8-10. These trees bear intensely bright yellow flowers that will draw many admiring eyes and is sure to be the focal point of your garden. They also attract hummingbirds, butterflies, and other pollinators. The flannel bush is a hardy, low-maintenance shrub that grows well in poor-quality soil. Just be wary of their dark green leaves, as the small hairs on the underside can irritate the eyes and skin. They also tend to be short-lived, according to the University of California’s Statewide Integrated Pest Management System.
- Crepe Myrtle: With its delicate showy blossoms and lovely fall colours, the crepe myrtle is a small-to-medium deciduous tree that looks fantastic as an ornamental tree, and can even be used as high hedging. Though the typical crepe myrtle flower is pink, there are plenty of varieties that also come in white, purple, and lavender-blue. For gardeners who want abundant blossoms from mid-spring to early fall, the newer flower buds can be pinched to increase flower production.
- Weeping Bottlebrush: Also known as the red cascade, this fast-growing flowering tree can be grown as both a small tree and a shrub. The weeping bottlebrush is easily recognizable due to its long, drooping branches and profuse bright red flowers that grow outward like bristles, hence the name ‘bottle brush’. These trees are very showy, making a vivid, attractive mark on your landscape. Their flowers and small fruits also attract plenty of pollinators and mammals. These trees are easy to grow, with little maintenance required.
- Other flowering trees: Jacaranda, Weeping Bottlebrush, Crepe Myrtle, Tea Olive, Acacia, Royal Poinciana, Carolina Cherry Laurel, Southern Magnolia, Plumeria, Camphor tree, Yellow Trumpet tree, Tipu, Orchid Tree, Evergreen Pear, Coral Tree, Gold Medallion, Oleander
- Eucalyptus: Native to Australia, the fragrant eucalyptus is best known as a food source for the adorable koalas that share their native habitat. In these environments, these trees, with their silver and blue-green leaves, can soar over 60 feet tall. However, in your zone 10 home garden, they are more likely to reach around 10 feet maximum. The eucalyptus is a fast-growing, sun-loving evergreen that grows best in surroundings that mimic its natural environment. Unlike the koala, eucalyptus leaves, bark, and sap are toxic to humans and pets.
- Mexican Fan Palm: For gardeners living in a hot, dry climate, palm trees are often the easiest and most accessible type of evergreen tree to plant. And there are plenty to choose from in zone 10, such as the Mexican Fan Palm which requires relatively little water or maintenance. With their fanning fronds, dried skirting and thin trunks, these trees are a tall and eye-catching addition to any arid landscape. Just keep in mind that these palms are considered invasive in Florida, California, and Hawaii.
- California Nutmeg: While the California nutmeg is only native to California, it can be grown in most zone 10 landscapes. These evergreen conifers are tall, with a wide spreading growth habit, pyramidal shape, and thick, fissured bark that makes it a compelling ornamental tree. It is shade tolerant and grows best in moist, rocky soil. In California, this nutmeg-yew tree has a long history of use in bow-making, basket-making, furniture-making, woodworking, fencepost production and more.
- Other evergreen trees: Leyland Cypress, Wax Myrtle, Brazilian Pepper Trees, Bishopwood, Australian Tea Tree, Eldarica Pine, Monterrey Pine, Knobcone Pine, Torrey Pine, Fan Palm, King Palm, Queen Palm, Date Palm, Bismarck Palm, Cuban Royal Palm, Toyon, Lemonade Berry,
- Carolina Cherry Laurel: Named for the maraschino cherry fragrance emitted when its leaves and flowers are crushed, the Carolina Cherry Laurel is a small evergreen native to the southern United States. It is an attractive tree with plenty of uses in landscape gardening. Its evergreen foliage, white blossoms and black berries make it a pretty ornamental, and it can also be grown for hedging, as a windbreak or privacy screen, and in foundation planting. These trees are hardy and low maintenance, only needing to be pruned once a year.
- Southern Live Oak: This oak species isn’t just a prized native in the south – it’s a classic American icon, prized for its broad trunk, majestic crown and sweeping limbs. The southern live oak is unusually graceful and one of the few evergreen oaks that are evergreen. This tree is guaranteed to add a touch of old-school elegance to your property, just make sure you have enough space for it – the enormous spread of this oak’s branches (up to 70-90 feet!) make it one of the largest trees in the south.
- Arizona Ash: Native to the southwestern US and some parts of Mexico, the Arizona Ash is an attractive deciduous tree that thrives in warm climates and grows in zones 7 to 11. With bright green oval leaves, golden fall foliage, and textured grey bark, it adds a touch of sophistication to your property. But be warned – the Arizona Ash is relatively short-lived, typically living for less than 50 years, so it is not an ideal choice of native if you want a tree for generations to enjoy.
- Other native trees: Turkey Oak, Wax Myrtle, Arizona Ash, Island Ironwood, Baja California Birdbush, Northern California Walnut, Joshua Tree, California Box Elder, Florida Strangler Fig, Geiger Tree, Gumbo-Limbo, Lignum Vitae, Pigeon Plum, Arizona Sycamore, Arizona Walnut, Desert Ironwood, White Thorn Acacia
Vegetables for Zone 10
- Eggplants: While eggplants can sometimes be tricky to grow, with the right conditions these delicious vegetables can thrive. It’s important to remember that eggplants love hot weather, so these summer plants should be grown through the hottest parts of the year. They should be planted when soil temperatures reach a minimum of 55-60 degrees F, though 70 or higher is preferred. These plants take around 16-24 weeks to grow from seed to harvest. Eggplants should not be planted in soil where potatoes, tomatoes, and peppers have previously grown.
- Arugula: Able to grow in most USDA zones, including zones 2 to 11, arugula is a leafy annual vegetable most often used as a salad green, like lettuce and baby spinach. Arugula is a cool-season vegetable and grows best between 45 and 65 degrees, so any planting in zone 10 should be done outside of summer. Arugula only needs 40 days to reach harvest, so it’s possible to grow it twice, in fall and winter/spring.
- Tomatoes: Most of us know that the juicy red tomato is technically a fruit, but for the most part it is grown as a vegetable. These summer-loving plants need heat and typically cannot grow in temperatures below 60 degrees F. Tomatoes will take between 50-100 days to reach maturity depending on the variety, and there are plenty of varieties to choose from: from cherry to beefsteak to Roma, there is a tasty tomato variety that can fit any palate.
- Other vegetables: broccoli, radish, arugula, carrots, celery, brussel sprouts, celery, tomatoes, eggplants, cucumbers, sweet potatoes, beans, beets,
Perennial Flowers for Zone 10
- California Poppy: Blooming in spring and early summer, the delicate California poppy is a perfect choice for gardeners who want profuse, vividly colourful perennial flowers without needing to invest too much time or effort. Though they are best known as orange poppies, they can also be grown in red, white, and yellow. California poppies grow so fast and in such abundance that they can often blanket the landscape, and they require very little water, making them perfect for areas susceptible to drought and water restrictions. The University of Florida Gardening Solutions site recommends planting California Poppy in the fall for a spring display.
- Blazing Star: The unique-looking blazing star, also known as Liatris, is a great choice for gardeners who want an unconventional aesthetic for their flower garden. The flowers of the blazing star grow in long, upright spires, with small, bright purple blooms erupting from every side. These flowering plants can reach up to 6 feet tall, and it can take up to 2 years for blooms to appear. It fits well as a border plant, in pollinator gardens and as part of a native plant garden.
- Mojave Aster: If you live in an arid, rocky, desert-like zone 10 environment, Mojave aster is the perfect perennial to grow. This aster variety grows naturally in harsh environments in Nevada, California, and Arizona – as long as the soil is well-draining they will grow. Their yellow centres and purplish-lavender petals add a pop of colour to any dry landscape, and while they bloom in spring they can also flower a second time in fall with the right amount of rainfall.
- Other flowers: Tickseed, Button Brittlebrush, California Fuschia, Beach Sunflower, Passionflower, Desert Beardtongue, Desert Mallow, Mojave Aster, Azaleas, Orchids, Petunias.
Herbs for Zone 10
- Curry Plant: Though it is rarely grown in the US, the native Indian curry plant thrives in hot, tropical environments, and can be grown in zones 8 to 12. These small trees reach heights of around 30 feet, and their delicate bright green leaves are harvested fresh and used to flavor curries and other dishes. These trees also produce small white flowers and black fruits, neither of which are suitable for consumption. Curry trees like full sun and plenty of humidity.
- Rosemary: This culinary herb is used prolifically around the world, and is one of the most useful cooking ingredients you can have on hand. Not only is it useful, but the fragrant rosemary smells delicious and looks lovely in a herb garden or border with its thin branches, narrow grey-green leaves and blue and white flowers which bloom in spring and summer. Rosemary is a low-maintenance, perennial evergreen that thrives in hot weather, though some varieties have been cultivated to withstand lower temperatures and frost.
- Hyssop: Despite being a part of the mint family, the Mediterranean hyssop is not grown nearly as often as its counterparts. However, hyssop has plenty of its own medicinal and culinary uses, and it doesn’t spread as prolifically as its relatives. And best of all, this semi-evergreen shrub will look lovely in any garden, with its rounded growing habit and long, delicate flowers that can come in blue, pink, purple, or red. Hyssop also works well in border planting, edging, flower gardens and can be grown in containers.
- Other herbs: Sage, Dill, Basil, Sweet Marjoram, Fennel, Oregano, Turmeric, Lavender, Rosemary, Peppermint, Lambs Ear, Hyssop, Bay Leaves, Bergamot, Borage, Chives.
Understanding the USDA hardiness zone you live in is an important step for any gardener in the US. It helps you to understand which kinds of trees, vegetables, and flowers can be planted on your property, and when and how they should be planted. But knowing your growing zone is just the beginning.
There is plenty more to learn as a zone 10 gardener – including the local weather patterns and microclimates, soil type and quality on your property, and the unique, detailed growing requirements of every plant you wish to grow. Consider the contributing factors of your environment beyond zone temperatures – will your plants be at risk of salt spray or urban pollution? Will you have access to adequate water during the high season?
Learning what you can about your property, and giving your plants everything they need to grow and thrive is essential. If you do, you’ll be sure to have a healthy and abundant zone 10 garden in no time.