Our Whanganui landscape has a diverse range of soil types and numerous microclimates all influenced by variances of the landscape.
The areas closer to the sea such as Castlecliff, Gonville and Springvale are more mild and less prone to frost than areas inland such as Aramoho, Okoia and Fordell which can get significantly colder.
These areas, however, do not experience the salt laden winds.
This diversity allows a wide and varied range of garden plants to grow in our region and what may thrive in one garden will not survive in a garden a few kilometres away across the city.
To ensure success when the conditions are tougher to grow in we need to choose plants suited to the situation rather than all our favourite plants.
One of the frequent inquiries we have in the garden centre is about what plants will withstand a dry situation. There are a good range of plants available that once established will be far hardier to withstanding dry summer conditions than others.
To ensure success thorough preparation should be done when planting. These steps are simple but will make the difference between a job done once or a job that has to be done again.
1. Select dry loving plants.
2. Digging a hole 2-3 times the size of the root area of the new plant and plant into a mixture 50:50 of compost such as Natural Bark Poultry Compost and the surrounding soil.
3. Using an appropriate root establishment fertiliser for the plant such as Ican Slow Food.
4. Mulching around the completed planting with newspaper and bark chip, Feeding Mulch or similar.
5. Provide weekly deep watering for December, January and February in the first two years while these plants are getting their roots established.
Dry loving garden plants you should consider;
Bottlebrush (Callistemon) is a plant that thrives in dry, sunny areas of the garden. There are a number of varieties that grow to different heights suitable for small or large garden situations. My favourites that do well in Whanganui gardens are Callistemon Red Clusters and Callistemon Little John.
Callistemon Red Clusters has stunning bright red flower spikes that cover the plant in abundance during spring and summer, though it usually has a few flowers on it throughout the year. This variety grows about 3m high.
Callistemon Little John is a compact dwarf growing bottlebrush. It only grows around 1m x 1m so is suitable for smaller gardens and shrub plantings. It produces masses of deep red flower brushes tipped gold mainly through spring and early summer with occasional blooms almost year round.
Strappy leaved plants such as flaxes, Dianella and Lomandra are useful in the dry environments and can form colourful contrast and structure to a garden.
These look good when used with the smaller growing grass varieties. Species such as the mini toe toe and the brilliant orange foliaged Carex testacea provide excellent landscaping opportunities when used in groups of three, or in larger mass plantings, using the colours of the grasses to contrast against one another.
Lomandra grasses have come to the fore in New Zealand in the last five years or so. They are being recognised for their general hardiness, the attractive form and structure they can bring to a garden through the movement they offer in the wind, the range of colours that are available and the ease of care.
Lomandra grasses are generally self cleaning, meaning that old foliage shrivels and disappears from the plant rather than 'hanging on' and needing to be removed by hand for the plant to look good. A stand out variety would have to be Lomandra Lime Tuff.
It has a spiky fresh green appearance and its growth and survival in tough situations can best be described bullet proof. It grows to a useful 50cm x 50cm size in sun or part shade situations. In the summer months it produces sweetly fragrant flower spikes that sit down amongst the foliage.
This plant can be used to a highly attractive effect planted amongst a larger growing darker coloured flax. As well as a garden specimen planted in groups of threes or fives or more, Lime Tuff also is the perfect pot specimen. Being so drought tolerant it is great for the sunny patio or outdoor living area.
A favourite for coastal gardens is a dwarf variety of pohutukawa called Meterosideros Tahiti. This plant grows about 1m by 1m and has brilliant orange-red flowers during summer and into the autumn. It makes an excellent plant in the garden or in pots and handles the tough conditions we are talking about today.
Another of the best performing small growing plants for dry areas is the Morning Glory, Convolvulus cneorum, not to be confused with the problem weed of the same name! This plant is not invasive and offers almost year round colour.
White trumpet flowers are 3-4cm across with bluish tingle, shaded yellow in the throat. It grows 60cm high by 1m wide, the foliage is a stunning silvery-grey.
A family of NZ natives that perform well in the drier environment are the Coprosmas. Coprosmas have many varieties that excel in dry, hot conditions. They also attract the birds with the berries that develop each year.
The range of varieties is diverse with a number of colourfully leaved shrubs growing about 1m-1.5m high. One of the most popular is Inferno.
Coprosma Inferno was released in 2010. It quickly raced into the bestsellers' list. Its foliage colouring orange, red and pink during the summer months deepens dramatically as the weather turns cold, changing to deep reds.
There are also a number of varieties with 'divaricating' type foliage. This is typified with small leaves on branches that have a tangled appearance. Coprosma acerosa is a good one to grow in the home garden with orange-brownish appearance that can be used to good visual effect when contrasted with other plants.
It has a spreading habit, and is excellent for holding sand and banks together in harsh conditions.
Also to consider in the coprosma family are the groundcover varieties. Coprosma Hawera and Taiko varieties are excellent for covering banks.
A NZ native tree that thrives in dry conditions is the pohutukawa; these are certainly one of the most popular when a large tree is needed. Other NZ natives include some of the Pseudopanux varieties and Griselinia.
There are a number of other plants that originate from hot dry climates of Australia and South Africa that are suited to these garden situations.
These include; Leucadendrons, Protea, Banksia, Westringia, Grevillea to name a few. I also haven't managed to mention ceanothus, rock rose, escallonia and feijoa that do well in the coastal and dry environment too.
So don't despair if you have had a few failures in a dry situation - there is quite a variety of things that you can grow.
Gareth Carter is general manager of Springvale Garden Centre