If you live in the warmest parts of the USA, in zones 9, 10 and 11, gardening is very different. Many of the common plants in cooler zones will not grow, because they need periods of cold weather in winter, and there are simply not enough cold days for them to flower, or even grow successfully. Very hot summers and high humidity defeat others, so moving to a hot area can be traumatic for northern gardeners. Perhaps you have always lived in these areas, but are only just starting to garden, or perhaps you are moving here from a garden further north. In either case, learning to garden in warm zones can be tricky, so let us help you understand the issues, and what plants you can grow – there is an exciting range of plants available for you to grow, and great gardens to create.
Some of the plants that grow outdoors in the warmest areas are also seen as indoor plants. If you are moving to a warm area from the north, it comes as a surprise to see that Weeping Fig tree you had in the living room suddenly growing as a 30 feet tree, or a big hedge. That Cast Iron Plant from the dark corner in your bathroom is suddenly larger, and can fill beds in shady parts of your new garden. Palm Trees tower over your head, their enormous leaves waving in the breezes. This tropical look is probably part of the reason you came, so now you are here, enjoy the excitement of a whole new range of plants for your tropical garden.
With such a wide range of diverse plants available, you can find plants for just about any need you have in your garden. For hedges, the Weeping Fig Tree has lovely glossy foliage and a dense, evergreen habit. Grown as an informal screen, or clipped into a hedge, it can reach 40 feet tall, so hedges of any size are possible, from a few feet to as tall as you want. Bamboo Plants make great screening – just remember to choose the clump-forming kinds if you don’t have a lot of room, or install a root barrier for spreading types, or they can take over a large part of your garden.
In drier areas with hot summers, the Italian Cypress is terrific for hedges, and takes high temperatures with ease, and stands some frost too. Some disease problems can occur in very humid areas, so check around if local gardeners are growing it, before planting. Various Privet Trees are also great for screening, and many have scented flowers too – just be careful with your selection and avoid the more invasive types.
For specimens on lawns, Palm Trees look magnificent, and they don’t cast a lot of shade, so other plants will grow well beneath them. There are many to choose from, and if you are in a transition area between tropical and temperate zones, then some, such as the Windmill Palm, will even grow in sheltered parts of zone 6. Most of the other Palm Trees are happy in zones 9 and 10. The King Sago Palm is another hardier palm-like plant, for zone 8, that only grows to about 6 feet tall, and makes a beautiful specimen in a smaller garden or town home.
Citrus Trees are always welcome in hot zones, and many will tolerate brief periods of frost too. Their beautiful evergreen foliage, in rich, glossy green, is always lovely, but it is the fruits that steal the show from fall to spring. Even if you don’t get around to eating them all, they hang on the trees for months through winter, looking just gorgeous.
Another striking specimen is the Fiddle Leaf Fig, which outdoors makes a large bush, with many upright stems, showing off the massive leaves, like giant violins. There is the Madagascar Dragon Tree, another smaller tree-like plant for a lawn or courtyard, or the bold Yucca Tree, with its thick trunk like an elephant’s foot. Familiar as a houseplant, when grown outdoors it becomes a grand specimen, with huge spikes of white flowers in late summer.
Then of course there are all the plants for full sun and dry soil, like the various clumping Yucca Plants, with their colorful gold or blue foliage, and the fleshy century plant, or Blue American Agave, which tolerate even the driest spots.
To fill beds beneath trees, nothing beats the Cast Iron Plant, with its tall, upright leaves. It’s able to thrive in dark, dry spots, and is perfect for easy greening of difficult areas. In sunny areas you can bring in lots of color with plants like the Fireworks Fountain Grass, which is perennial in tropical areas, with just a winter haircut.
With such a diverse group of plants that enjoy hot zones, there is something for every part of your garden. Most enjoy sun, and many are drought-resistant, at least once they are established. If you have a larger garden you probably have both sun and shade, so simply choose suitable plants. Like gardening anywhere else, digging and preparing the soil is important, and adding compost to poor, sandy soil will do wonders for the growth of your plants. Mulches are great ways to conserve moisture, and they protect the soil from being compacted and eroded during heavy tropical rainstorms, so mulching your beds is always a good idea.
It sometimes seems that in these mild climates, plants will just grow whatever happens – and some will – but for the best look, and flowers and fruit, regular fertilizer, blended for the type of plants you have, always makes a big difference. Don’t forget to water regularly while plants are young, even if they are drought-resistant when older. Pests and diseases can be more common, since winter doesn’t kill them off, so keeping your plants healthy and growing vigorously, with water and fertilizer, becomes even more important as your first-line defense against pests.
With long seasons and warm weather comes vigorous growth, and plants become large much more quickly than in the north. Because of this, regular trimming and pruning are often needed to control the sizes of bushy plants and hedges, but you generally don’t need to pay much attention to when in the year you do it.
Let’s look a bit more closely at some of the plants you can grow successfully in hot zones:
Palms rule supreme in the tropical garden, with the taller kinds towering high in the sky, and smaller ones bringing their unique foliage closer to the ground. Some have single stems, but others grow into clumps, so choose what is best for your needs. There are many, many palms, but some stand out for special attention.
For the smaller garden, two choices stand out. The King Sago Palm (Cycas revoluta) is not really a palm at all, but an ancient relic of the earliest ancestors of conifer trees (pine, spruce, etc.). It certainly does look like a palm, though, with its arching glossy leaves and thick, furry trunk. Growing slowly into stems 6 feet or more, and 3 to 6 feet across, with a wonderful ‘presence’, this is a ‘must have’. Second is the Pygmy Date Palm (Phoenix roebelenii), which is a graceful small palm eventually passing 10 feet in height but staying much smaller for many years.
The Queen Palm (Syagrus romanzoffiana), a symbol of Hollywood boulevards, is a majestic taller palm, reaching 50 feet, with thick plume-like leaves and a slender gray trunk. The Christmas Palm (Adonidia merrillii) is a smaller palm, reaching perhaps 20 feet, and it is unique for its large clusters of red berries in the holiday season, while the Areca Palm (Dypsis lutescens) grows into a dense bunch of slim trunks, ideal for screening or filling larger garden spaces.
Beautiful evergreen trees, with glossy leaves of dark, rich green, all citrus trees, from lemon to orange, kumquat, mandarin and grapefruit, grow happily outdoors in warmer zones. Too numerous to outline here in detail, all of them are great choices for specimens, and between the richly-scented white flowers in spring, and the fruit ripening to orange or yellow from fall to spring, they bring lots of color through the winter months.
There are hundreds of Fig Trees, including of course the edible fig, but for tropical gardens two stand out. The Weeping Fig (Ficus benjamina), familiar as a houseplant, grows outdoors into a tall tree with a graceful, rounded crown and pendulous young branches. It makes a dense evergreen screen too, clipped or unclipped, and it is one of the most versatile and useful tropical trees. It’s relative, the Fiddleleaf Fig (Ficus lyrata), is very different, with foot-long leaves shaped like a violin. Outdoors it sends up many stems from the base of the plant, becoming a large shrub, and really showing off that fabulous foliage.
In drier tropical and sub-tropical areas, or just in poor, dry soil almost anywhere, the various Yucca Plants are invaluable. Once planted they need almost no care, and their dense clumps of upright leaves, reaching about 3 feet in height, look best when you grow varieties with golden leaves, like ‘Bright Edge’ or ‘Golden Sword’, or blue leaves, like ‘Blue Sentry’. Perfect for edging, or planting in any sunny spot, they are also terrific at the beach, since salt spray doesn’t bother them at all.
Quite different is the Yucca Tree (Yucca elephantipes), which has a very thick trunk, flaring out at the base, topped with a spike of deep green leaves. This is a substantially sized plant, for a lawn or on the sunny side of a house.
Easily distinguished from Yucca by the thick, fleshy nature of their leaves, plants live the Blue American Agave are perfect for full-sun, dry spots in any tropical garden. Reaching 6 feet tall and wide, one day they might even send up an enormous flower spike, many feet tall, topped with white bells.
The various Dracaena plants are often seen as houseplants, but outdoors they make striking medium-sized specimens, with thin, tapering leaves in a cluster topping slender stems. Their more delicate look fits well among smaller plants, or in smaller spaces. They may look slight, but they are as tough as the Yuccas when it comes to sun and drought, so they are a great low-maintenance choice.
There are so many Tropical Plants for warm zone 9 and 10 gardens, it is hard to stop describing them. Here at the Tree Center we offer plants for everyone, so don’t think that we only cater to northern gardeners – no, if you are in California or Florida, we have lots to offer you.