USDA Plant Hardiness Zone 11
Gardeners in USDA Plant Hardiness Zone 11 live in the warmest range of all the growing zones. The average coldest winter temperature falls between 40 and 50 degrees F, making the possibility of frost or freezing weather almost non-existent. The limited geographic regions in Zone 11 include parts of Hawaii as well as Southernmost Florida, including Biscayne Bay, Key Largo and Key West. Tropical plants, including many types of fruits, prosper in these warm climates.
These plants sail through the heat in Zone 11:
• Eucalyptus (Eucalyptus cinerea). Beautiful form and fragrant foliage make eucalyptus trees a real attention-getter in the landscape. Coin-shaped leaves in shades of silvery-blue are arranged around stems that you can cut and bring indoors for long-lasting floral arrangements. Eucalyptus is fast-growing (up to 8 feet per year), drought-tolerant and insect- and disease-resistant.
• Windmill Palm (Trachycarpus fortunei). Palms are quintessential tropical plants. The Windmill Palm is a low-maintenance accent for any Zone 11 yard.
• Royal Empress (Paulownia elongata). With its stunning display of lavender flowers, the Royal Empress tree commands attention in any landscape. But the tree we offer is not the one typically known as a "weed tree" (because of its prolific re-seeding ability). Bred as a sterile specimen, a single tree stays contained in your yard.
Zone 11 is a paradise for citrus trees, which flourish in this warm climate. The sheer variety of citrus that can be grown easily turns any backyard into an orchard. Here's an at-a-glance example of Zone 11's citrus diversity:
• Navel Orange (Citrus sinensis 'Osbeck'). Sweet-tasting oranges, which are virtually seedless, are borne in abundance on trees that also produce fragrant orange blossoms.
• Calamondin Orange (Citrus mitis 'Calamondin'). Resembling a tangerine, calamondin orange fruits are about the size of a small lime. Trees may flower and bear fruit year-round.
• Owari Satsuma (Citrus reticulata 'Owari'). Easy to peel and sweet for snacking, Owarai Satsuma fruits grow on trees that typically reach a height of only 10 feet.
• Ruby Red Grapefruit (Citrus x paradisi 'Ruby Red'). As the first grapefruit to be given a U.S. patent, Ruby Red has a longstanding history of quality. Although the rind is the traditional yellow color of other grapefruit varieties, the flesh has a rich ruby color.
Citrus may be king in Zone 11, but these fruits come in a close second:
• Cold-Hardy Avocado (Persea americana 'Mexicola Grande'). Healthy and flavorful, avocado trees thrive in the warm climate of Zone 11. Mexicola Grande avocadoes are of the highest quality, with a sweet and buttery taste.
• Grand Naine Banana (Musa 'Grand Naine'). One of the Cavendish bananas, this tall plant produces high yields of fruit, reaching a height of up to 10 feet. Grand Naine Banana is also more resilient in windy areas than other banana varieties.
• Dwarf Cavendish Banana (Musa acuminata). A shorter version of taller Cavendish banana varieties but with full-size fruits, which are easier to reach at harvest time.
• Soursop (Annona muricata). This unique tree bears unusual fruits that taste like a combination of banana, pineapple and papaya. Although the spiny fruit looks formidable, the spines are pliable and won't stick your fingers when you harvest them.
One of the signature plants that define tropical landscapes, bougainvillea vines come alive with vibrant color provided by their showy bracts that surround the true flowers. Bougainvillea flourishes in the heat without becoming limp or struggling. Plants grow on trellises, arbors and pergolas to enhance garden entrances, sitting areas and patios. Barbara Karst Bougainvillea (Bougainvillea 'Barbara Karst') puts on a spectacular show with magenta blossoms, which cover sturdy stems that reach up to 30 feet long. Sundown Orange Bougainvillea (Bougainvillea 'Sundown Orange') has coral-pink blossoms and New River Bougainvillea (Bougainvillea 'New River') has purple blooms.
As plant cousins to turfgrass, ornamental grasses add movement and texture to the landscape. One ornamental grass that's also edible is Lemon Grass (Cymbopogon citratus). This culinary herb adds flavor to soups, stir-fry dishes, meats and vegetables. You can even make tea with the long leaves or crushed stems. Citronella (Cymbopogon nardus) is a clump-forming ornamental grass, with flattened leaves that arch gracefully and release a citrusy fragrance.