Think of the tropics and images of leafy lush spaces filled with exotic vibrant coloured plants come to mind. Those lucky enough to live in a warm climate, both moist and dry, have a huge variety of gorgeous subtropical plants to choose from. I am passionate about Subtropical gardens and I adore subtropical plants – Elegant Kentia palms, ancient cycads, dark-stemmed taro’s and bright coloured Hibiscus to name just a few of my favorites. Over the next few columns I will introduce you to a number of plants for a milder climate. My aim is to inspire and inform you, so you can create your very own private paradise.
Today’s subtropical gardens have influences from countries such as Asia, Australia, the Pacific Islands, as well as Central and South America. It has become a popular choice for many keen gardeners for a number of reasons. Compared to a cool climate, traditional garden the subtropical garden has a strong emphasis on plant form and foliage verses flowers. Flowers are often incidental, and when they are around, they dazzle you with their eye-catching, bold colours.
People are often asking for ‘low maintenance’ gardens. If I were given a dollar every time someone asked me that, I would be a millionaire! If this is the case, I will often recommend a subtropical style garden, providing the site and conditions fit.
Gardening and maintaining a subtropical garden requires quite a different approach. They are generally a lot less demanding than other garden types. Plants chosen for their bold, interesting foliage are easier to maintain. There is no regular pruning or preening, lifting and dividing of plants. Foliage stands up to rain much better than do flowers. You will however find yourself cutting plants back, mulching and feeding. Most subtropical plants are prolific feeders, mostly during the warmer months. However, this is never a complex matter. Plenty of organic matter, chemical or organic fertilizers have great benefits. Growing happily amongst layers of compost and mulch. The idea is to closely reproduce the processes occurring around them in their natural habitats in forests, mountainsides and gullies in subtropical latitudes around the globe. An important tip for preparing and maintaining a subtropical garden is to raise the beds and continue to layer and build them up. With a warm climate and regular rainfall and well drained fertile soil you can quickly have an exotic-foliaged garden
From Kaitia, to Auckland, Hawke’s Bay and the Coromandel, subtropical plants will flourish in a variety of conditions, provided you follow some simple growing guidelines. In areas that are not strictly subtropical, it is possible to create an artificial microclimate that closely mimics these ideal growing conditions. The definition of subtropical basically means areas with warm to hot summers and mild, frost-free winters with temperatures falling to a possible 5.C and rainfall ranging from 1000-2000 mm a year.
Plant Architecture and Design
From a design point of view, the Subtropical garden is a very relaxed, informal style with no firm design rules. The plants are the focus of the garden and lots of them. They are layered and grouped together to create a lush, predominately green backdrop for year-round interest. If you are passionate about fabulous foliage and vibrant colour and you would rather be entertaining in your garden then maintaining it, then you will love this style of garden. The idea is to showcase foliage in attractive, contrasting planting combinations that are natural, yet spectacular.
When planning a subtropical garden from scratch you should begin by defining the framework of the garden. Understanding their form and growth heights will help you position your specimens in the best location. Tall, vertical plants such as Palms are great backdrops to other mixed tropical species such as Cannas, Taro’s and Hibiscus and are best dispersed in the middle as foreground features
One main rule for a subtropical garden is that any additional elements or features should be of natural materials. E.g. rock, water, pottery urns and pots.
Plants with strong visual impact provide drama and excitement all year round, such as Palms, Banana’s, Cycads and Yuccas. Whether your garden is large or small, in shade, sunny or windy conditions, there are many spectacular plants that you can grow with a bit of planning.Palms
Tall and majestic, palms are distinctive and iconic to the subtropical garden. Their exotic form and foliage makes them a strong garden feature. Palms look great either as singular lawn specimens or planted in groups. Whether your site is large or small there are a number of varieties to suit your particular location.
Besides their natural beauty, there are many advantages to growing palms. Apart from removal or gathering up of the occasional dead fronds there is very little else to do beside feeding and watering. They do not need pruning and are largely insect/pest free. Because of their compact fibrous root system they can be grown in tight areas where space is limited and can quickly provide you with height and structure within the garden. You can plant them close to retaining walls and driveways. For most trees this would be harmful but with palms this helps rather than harms their growth. Palms love a confined, tight space to grow. Even if they do out grow a space, they are easily transplanted fully grown, at any time of year, making them ideal for an instant established look. Palms also make fantastic container plants, both indoors and outdoors, allowing them to grow for years in a confined space before having to transplant them out into the garden. Kentia palms are a slow growing variety that which look magnificent in large pots beside you pool or in a courtyard.
Over the last 10 years, palms have become more widely understood and utilized. They have become the signature plant of many landscaping projects. There are a number of established, gorgeous subtropical gardens that you can visit. Totara waters in Whenuapai, Auckland is one of my favorites. Visit Peter and Jocelyn’s garden and see for yourself the rare and unusual plants they have on display in their garden.
Choosing the best palm
The good news is that for the North Island there is a huge array of palms that are suited to our climate. The catch is selecting a palm to suit ones own environment. Therefore a careful analysis of your site is very important. Well-situated plants are less susceptible to pests and diseases and require less attention. To illustrate the point, here is a chart that lists the species most suitable for a particular microclimate whether it suffers snow in winter, dry all year round or will grow in a costal environment. Click here to view a downloadable Palm Planting Guide...
• Understand the environment that you plan to plant into.
• Check the soil, is it heavy and wet clay soil or sand and free draining?
• Is your site subject to frost?
•How windy is your site? Is it coastal, will salt laden winds likely to be a factor:
• Choose palms that fit proportionately with their surrounds. Beware of their location in relation to the sun, powerlines, drains, windows and neighbours.
• Choose a palm that is suitable to your planting site e.g. shade, semi-shade, full sun, windy, coastal
• Dig a hole at least twice the size of the width of the planter bag. Keep the same depth, allowing a bit of space underneath the root ball.
• Plant into good quality compost, prepare the hole with a handful of blood and bone, or slow release fertilizer. Plant on a mound if possible to help with drainage.
• Stake the palm if it is tall or on a windy site. Remove the stakes when the root system has been established and the palm is firm in the ground.
• Water thoroughly when planted. Water daily during establishment. Especially during the hot summer months.
• Mulch around the base of the palm. This helps to retain moisture.
• Feed your palm, especially in its first spring on site, with a fine granular fertilizer.
In my next column I will discuss other trees, flowering shrubs, leafy perennials, bromeliads and colourful climbers to accompany palms in the creation of a subtropical garden.
Thankyou to Liberte Palms for providing information on Palms.
Sandra is an award-winning designer based in Auckland.
Sandra Batley Dip LD
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