There is a lot of excellent information on the internet that may be helpful to the home gardener wishing to grow blueberries. The following is a brief outline.
Blueberries can be grown easily in the NZ climate provided the following is understood. The warmer areas are going to grow the Rabbit Eye and Southern Highbush best while the varieties best for southern areas are the Northern Highbush. Central areas will grow both well.
The plants prefer a more sheltered environment. They are also prone to frost damage from the time the flowers come out. During this period a frost of more than -2C is likely to cause damage to the fruit.
The plants do best in free draining acidic soils however most plants are reasonably tolerant unless the soil is heavy clay. In clay soils it is recommended that a raised bed of peat and sand is formed. Some commercial growers in Europe do their commercial blueberry growing in large pots, (some with thousands of plants)
A standard garden fertilizer is all that is required starting with a teaspoon or two for two year old plants increasing gradually as the plant grows. Be sure to sprinkle the fertilizer and wash it in.
It is important to ensure that the roots do not dry out over the growing season this may mean watering ever few days if you do not get rain.
Pests and diseases
The worst pest by far is birds. They will start eating the berries often just as they start changing colour. If you wish to get a crop in the home garden you will need to cover with some sort of bird net.
Choosing a Variety
There are literally dozens of varieties each with their individual characteristics in terms of size, flavour, and timing of ripeness. Below is a list of varieties available from Blueberry Country.
Early season is December, mid-season is January and Late season is February onwards.
Oneal Early season. This variety produces large sweet blueberries, and is many peoples favourite. It ripens early December and can produce a second crop late in the season (March).
JU83 Early season. Fruit of this variety ripen early December and is a heavy cropper, Fruit are small to medium.
Reka Early season. NZ bred variety. Produces a heavy crop of medium sized blueberries mid-December. Plant is upright and vigorous.
Blueray Mid season. This is a very resilient plant with a heavy crop. Fruit is soft with good flavour; the bush is upright and vigorous.
Bluecrop Mid season. This is the number one variety in the world. It is a heavy cropper and disease resistant. Berries are mid-sized and have good flavour. Fruit ripen over long period from late December to late January).
Dixi Mid season. This Variety produces large sweet berries on a large bush. Fruit is ready mid to late January.
Climax Late season. A vigorous and very productive blueberry, which are medium sized. Fruit ready from late January to late February. Rabbit eye varieties may produce bigger fruit when planted with another Rabbit eye
Tiffblue Late season. This variety is an upright large bush producing medium sized abundant blueberries. . Rabbit eye varieties may produce bigger fruit when planted with another Rabbit eye
Centurion Late season. Produces large quantities of small sweet berries. . Rabbit eye varieties may produce bigger fruit when planted with another Rabbit eye
Powderblue Late season. A late season blueberry (from mid-February) that produces medium size light blue sweet berries. . Rabbit eye varieties may produce bigger fruit when planted with another Rabbit eye