Plants for a Coastal Garden
If you are lucky enough to live within walking distance of a beach, you may have noticed that certain plants tend to thrive in your garden, whilst others are just not as able to cope with the salt laden winds of the coast.
There are two ways to handle planting in coastal environments. If you want plants that are not hardy to salty breezes you can protect them by planting a protective shelter around them. Alternatively, there are a plethora of interesting coastal hardy plants to choose from:
Trees and shrubs which can act as a protective barrier for less tolerant plants include Banksia –who’s spectacular flower heads are also valued for attracting, Tui and even Waxeyes ; Norfolk pine – although be aware these are extremely large trees growing up to a height of 50–65 m when mature; Callistemon (bottle brush) – which are also prized for their striking flowers. Cabbage Trees are a New Zealand icon and are a great addition to the landscape, especially in mixed plantings. Similarly striking are Pseudopanax, as well as the Puka and Puriri which both have outstanding foliage and berries which entice a multitude of birds including Kereru. Another classic NZ tree is the Pohutakawa, whilst the most famous Metrosideros excelsa can grow to over 10m tall, it has smaller cousins who grow to around 4 or 5 metres and even the dwarf Metrosideros polymorpha Tahiti, a shrub which reaches around a meter and has brilliant scarlet-orange flowers from mid-winter through spring. Manukas are also suitable to coastal areas as are Leucadendrons, which not only look spectacular, they require very little care once established and their vibrant bracts make great cut flowers.
As for hedging, the Cupressocyparis family make great tall hedging plants, as do Pittosporum, Phebalium (Satin Wood), and Griselinia. Grevillea banksia also makes a colourful screen. All of the Westringas are coastal hardy and provide a variety of hedging heights from 0.5m up to 2m tall.
And so to shrubs, Coprosma, Corokia, and Cistus (rock rose), are all suitable, hardy shrubs; as are Hebes, Lavender, and Rosemary which also serve the important role of attracting bees. Flaxes such as Phormium, Astelia chathamica and the sedge Carex testacea are also good hardy choices.The Kowhai Sophora Longicarinata is an excellent small tree to consider, with its graceful weeping form, fine dainty foliage and greenish-yellow flowers which are attractive to birds. Viburnum ‘Emerald Beauty’, and the Arthropodium cirratum and Arthropodium ‘Matapouri Bay’ all provide attractive white flowers. For something more exotic, look to Hibiscus, Protea, and Bird of Paradise.
Pimelia make for a hardy and fast growing groundcover, as do several types of low growing Coprosma such as C. acerosa and Coprosma x kirkii
Only very hardy climbers can withstand coastal climes. These include Bougainvillea (although be warned, as enticing as they are, these thorny customers can be difficult to keep in check), Ficus pumila, Hardenbergia, Pyrostegia (flame vine), also all make excellent choices, but none more so than the threatened Tecomanthe speciosa Three King’s Climber, which interestingly will only flower when it is growing horizontally.
The above list is by no means exhaustive, but serves to illustrate that there are an abundance of plants which are suitable to coastal climes. Of course with the correct shelter and care you can still include plants that aren't as tolerant of coastal conditions.
Whatever you plan to plant, it is important to give it the best chance of flourishing by ensuring the plant fits the site conditions, such as exposure, soil type, drainage, temperature, and sunlight available. Healthy plants growing in ideal conditions will be less likely to become diseased and are also less likely to be adversely affected by insect damage. If you work with the garden and choose suitable plants it will save you a lot of time and effort in the long run and reward you for years to come.