Growing Blueberries in Subtropical Australian Climates

Plant Description

The Blueberry plant is a free standing, thornless bush that does not require staking.  Depending on variety, the plants grow to  around 1 to 2  m tall and 1 m wide when mature.   Blueberries belong to the Ericaceae family and are  related to Azaleas and Rhododendrons. If grown on the right soil, blueberries are a relatively easy crop to grow.  They have very few pests and diseases and are an excellent plant for organic farms and home gardens.  Blueberries are presently experiencing high popularity and consumer demand because of the recognized health benefits due to the high concentration of antioxidants contained in their pigmented fruit.

Blueberries thrive in pots and are can be kept on balconies and in courtyards etc…..for the home gardener it is often easier to grow blueberries in pots than in the ground.

Soil

Blueberries prefer a deep, well-drained fertile soil, high in organic matter.   Like azaleas they are adapted to acidic soils and for optimal growth require a pH around 4.5–5.5 when they are planted in the ground.   Adding elemental sulfur or peat moss is the most effective and quickest way of lowing the pH of the soil. Alternatively, the addition of compost, manure or pine needles will slowly reduce the pH of the soil over time.   Plants growing in poorly drained or alkaline soils will struggle and not be productive. Shallow or poor draining soils can be improved by creating a raised bed to  assist with drainage.

For the home gardener growing blueberries in pots can be preferable to growing the plants in the ground. Blueberries absolutely thrive in pots and are very productive as long as they are watered frequently and grown in a well drained fertile potting mix.  If grown in pots with a pinebark based potting mix and controlled release fertilizer the pH is not so critical and a range from pH 6-7 is suitable.  It is best to use a premium potting mix that that meets the Australian standards.  Fertiliser in the form of slow release prills or organic pellets etc are required to supply the plants nutrient requirements.

Irrigation

Blueberry plants have a shallow fibrous root system and require  regular irrigation throughout the growing season.  They are not drought tolerant and will become unproductive if they are allowed to dry out. During the growing season and especially while they are fruiting, irrigation, several times a week is needed.  In general 2 to 3 megalitres per hectare are required for commercial blueberry production.  Mulching the plants with manure, compost or other organic mater will help conservative soil moisture and reduce weed competition. As the mulch breaks down over time it adds organic matter to the soil which helps maintain the acid soil conditions that blueberries require.  For optimal pot production the plants must be keep moist and generally require watering every few days.

Planting

North to north-easterly aspect is preferable to give maximum sunshine hours and the earliest production. Whilst other aspects can be used you will find south-facing slopes will be cooler and hence produce a later crop.  In pots it is best to keep the plants in a sunny position but they will tolerate dappled shade.  In the ground, plant spacing will vary depending on variety. Generally Southern Highbush plants are  spaced at 0.8 m to 1 m apart within rows with the rows being 3 m apart (3700–3300 plants/ha). Rabbiteye varieties, due to their greater vigour, are planted at 1.2 m to 1.4 m spacings within rows (2500–2100 plants/ha).  Running rows in a  north – south direction will maximise light inception.

Pruning

Flowers are generally produced on the previous seasons canes which form flower-bearing lateral branches in their second spring growing season.  After  three years these woody canes become less productive and should be  pruned at ground level.   Prune the plant after harvesting has finished (late summer /autumn), keeping only the strong, vigorous  canes and laterals, especially the ones shooting from the base  of the plant.  Open out the centre of the plant, and remove any weak twiggy growth.  The plant will respond to a hard cut back  and produce new vegetative growth and a bigger crop the flowing season. Blueberries are long-lived plants and will bear fruit for over half a century.

Pollination and Fruit Set

The flowers are attractive bees and other insects which are important for pollination and subsequent  fruit set.  In general, most  blueberries will produce fruit as a single variety but if possible it is best to plant two or more  varieties to improve fruit set and extend the harvest window.  Commercial plantings usually consist of alternate rows of two varieties that flower at the same time. Some plantings may have two rows of one variety followed by a single row of the other variety.

 Harvesting

The average mature blueberry bush should produce 4to 5kg or more of berries each season. The fruit grows in clusters of berries which do not ripen evenly. The fruit in any single bunch will ripen progressively, over a period of 5 or 6 weeks. Under-ripe fruit are usually a bit tart, so for maximum sweetness leave the berries on the bush for as long as possible. Wait for a week or so after final coloring has been reached, then pick the best and darkest from each cluster.  Being able to pick  blueberries when they are are at there optimal ripeness for your taste is one of the great benefits of growing your own.  Most commercially produced blueberries are picked early to minimize damage during handling and transport and to maximize storage times but this is often at the expense of flavor and quality.

Comments 34

  1. When you say blueberries respond to a hard cutback, I (& many people) aren’t sure exactly what that means. 12 of my 14 Blueberry bushes still only have the one main stem & have never grown any new canes, & the plants aren’t nice & bushy but only have laterals with leaves on the last 1/4 of each branch which comes off that original main stem. I’ve twice tried to prune what I thought was a lot more witthout cutting below the leafed parts of each branch. Can I or should I be pruning off that much to get them to grow canes & to get them bushier? I know they havent been cared for enough with consistent fertilizing & watering, & maybe the soil PH isnt low enough, but 2 did grow numerous canes (one plant being approx 8yrs old & the other being approx 4yrs old) but other plants being between 2-8yrs old have remained having only one main stem with no new canes, so I get very few berries, hence why I kept buying more new plants but something is wrong. Ive searched the internet for yrs on this topic re why new canes wont grow but still cant find anything written anywhere. PLEASE HELP !!!

    1. Post
      Author

      Hi Sue,
      It seems that pruning is not the issue. You could try just tip pruning the laterals to get them to start to bush out but I think you priority is to get the plants growing vigorously. Blueberries do not like to dry out, so make sure they are watered regularly through the growing season. Apply manure or slow release fertilizer at the start of the growing season. I would also spread elemental sulfur around the plants and mix it into the soil. 1/2 cup per plant… it is really quite effective in reducing the pH and helping with nutrient uptake but none of this will work unless the plants receive adequate regular water.

  2. Hello, I have a young Sunshine Blue which I purchased about 2 months ago, growing in a container and since transplanting it has made some considerable new growth. My concern is that the lower leaves appear similar to the older leaves in size and shape, although a little “furry “, but the further up the stem goes the leaves are huge in comparison to the rest of the plant (x5 or 6 times) and still have the furry appearance. The older growth has substantial fruit and new flowering buds. Is this an issue I should be worried about?

    1. Post
      Author

      Hi Jim,
      Leaf size can vary considerably on a plant depending on the environment, water and nutrition when the young leaves are developing. Blueberries are not grafted so if the leaves are all on the same plant there is nothing to worry about.

  3. I have Biloxi,Blue sharp and Gulf coast growing in an insect screened enclosure which excludes bee access will this affect the production of good berries ? Advice please.

    1. Post
      Author

      Hi Graham,
      Blueberries are pollinated by insects especially bees. The pollen does not transfer well with wind and evenly strongly self-fertile varieties benefit from insect pollination.
      I suggest you keep the enclosure open during flowering once the fruit has set, close it up.

  4. What varieties of Blueberries are best suited to The Granite Belt zone in QLd. I live 10 kilometres south of Stanthorpe at Glen Aplin where we wake to lots of frosts in the winter. I have 3 varieties at present in pots which I kept inside every night this year and put out in the sun every day. I have Powderblue, Sharp Blue and Brightwell which the Local Bunnings had and recommended them for this area. Although they are doing ok with some fruit, I did expect more fruit.
    They are potted in Azelea potting soil, with pine bark mulch, coffee grounds sprinkled on top and fertilised with Searles Flourish for acid loving plants.

    Are there better varieties of Blueberries for frost areas as I don’t want to have to bring them inside every night throughout winter for their life or can you suggest how to frost or winter proof them to survive outside.

    Cheers
    Sandy

    1. Post
      Author

      Hi Sandy,

      Of the low chill Varieties, Powderblue, Brightwell and Legacy are the most cold tolerant. In the Stanthorpe area these should be completely dormant in the winter so there is no need to move them outside during the day. Move them outside in Spring. They should produce well in pots. I would used some controlled release fertilizer like osmocote/ nutricotes at 5g per litre of potting mix, applied every 6 months. No need for they coffee ground in the pots.. that is OK in the ground but not so good in pots. If they are looking a bit yellow you could add a couple of teaspoons of elemental sulpher. Keep in mind blueberries do not like to dry out so keep them watered regularly. If you want to grow plants in the ground you need to plant the high chill cold climate varieties ( Northern Highbush) like Brigitta, Duke, Elliot etc

  5. Hi Maria,
    what type of blueberries do to recommend for the central coast NSW
    my brother had a farm near Grafton NSW the sharps were too sour however there was one a Froradale I think that gave fruit later in the year Dec / Jan it was very large berry and very sweet not like the ones we get in the shops down here
    regards John

    1. Post
      Author

      Hi Maria,
      The beauty of growing your own blueberries is that you can pick them when they are fully ripe and at their sweetest. Gulf Coast is a nice sweet variety. For a later season fruit Powderblue and brightwell are suitable.

  6. Hi i am located in Caboolture area and have planted 5 blueberry trees a few months back. They are now flowering and I am wondering when to fertilise them and also any general info about them as i am new to growing any fruit. Many thanks for your time

    1. Hi

      Can I please ask what type of blueberry you have planted and where you got them?

      We’re in Brisbane and has always thought it was too hot!!

      Thanks
      Alise

  7. Could you please advise the best type of blueberry plants for growing in Emerald in the Central Highlands of Queensland? Also what is the best time of year to plant blueberry bushes and whether to plant in pots or in the ground?
    Thank you.

    1. Post
      Author

      Hi Olga, Both the Southern High Bush types, (Gulf Coast, Sharpblue, Misty, Biloxi and Legacy) and the Rabbiteye types (Brightwell, Powder Blue) would be suitable. They can be planted all year round if they can be regularly watered but Autumn, Winter and Spring are optimal. They are easier to grow in pots. If planting in the ground you must ensure that the soil pH is adequate. Please see our blog on growing blueberries https://fruittreelane.com.au/blueberries/growing-blueberries-in-subtropical-australian-climates/

    1. Post
      Author
  8. I purchased 2 Gulf Coast blueberries and 2 Sharp Blue blueberries from you 2 weeks ago. 2 are with a friend on the coast at Elliott Heads and I have potted up 2 with azalea mix in Bundaberg. All 4 plants appear to have rust on the underside of their leaves. What is the best course of treatment for them.

    1. Post
      Author

      Hi Alison,
      in colder climates, blueberries are naturally deciduous and lose all their leaves in the winter. If the winter is not quite cold enough, the leaves often get spotty, turn colour but do not drop off. The best approach is to remove and discard all the leaves.
      It is unlikely that it is rust, but because the plant is going it dormancy it is moving all the nutrients out of the leaves and storing them in the stem for winter. This results in the leaves looking unthrifty and susceptible to leaf spots. Take the leaves off and come Spring all the new growth will be fine.

  9. Thank you for an informative & interesting article.
    I have just planted 3 plants in azalea mix in pots. As it is May in Bayside Brisbane I’m expecting good growth & some fruit next spring.

    1. Post
      Author

      All the best with the blueberries.. be sure to add some slow release fertilizer to the mix and reapply every 3-4 months

    1. Post
      Author

      Hi Gretal,
      The Southern Highbush varieties Gulf Coast, Sharpblue, Biloxi, Misty and Legacy would all be suitable. The rabbiteye varieties Brightwell and Powderblue would also suit the Perth climate. It would be critical to ensure the soil pH is around 4.5 and 5.5 for best plant performance.

  10. Pingback: Blueberries for Good Health and How to Grow in Pots (subtropical Australia) | Oz Naturals

  11. i live in Mackay, Queensland and was wondering if i could grow blueberries there. if so what varieties should i plant.

    1. Post
      Author

      Hi Gil,

      The Southern Highbush varieties will grow and fruit in Mackay.. These include Gulf Coast, Biloxi, Misty and Sharp Blue. If you are only planting one I would plant a gulf coast as they are very self-fertile. If you’re a planting a few I would plant a mixture.

  12. James from the Obi Obi Valley back of the Sunshine Coast Qld
    I have had great success with potted plants that Ive had for the past seven or eight years . but
    Currently they appear to be not so well one has a wonderful array of autumn coloured leaves the other still green leaves both plants are approxly 1800 high, still have a few flowers and the occasional fruit at various stages of ripeness. I use a slow release fertiliser regularly also use some fish emulsion fertilizer on a not so regular basis. All pots were planted in azalia potting mix, I have added some wood chip from time to time on top.
    My question is would it be wise to repot this time using a layer blue metal gravel in the bottom of the large pots for balist, then finish as before with the azalia mix, Im concerned the current potting mix could be exhausted.
    My thoughts is this may give the bushes when a new zest for life.
    All 4 of my pots have clover type weeds covering them around the bases of the bushes
    Id appreciate your comments also is there somewhere on the Sunshine coast that I can speak with a knowledgable person about the blueberries
    Thank you James

    1. Post
      Author

      Hi James,

      I think your blueberry plants will benifit from being potted up into larger pots or planted in the ground. Sound like they are quite large bushes and the root congestion in the current pots is starting to become a limiting factor.

  13. Hi, are blueberries suited to coastal gardens? We are on the Gold Coast, on the beachfront and have the ocean winds most of the time.
    If yes, which variety would you recommend?
    Thank you

  14. Hi,
    We live in Glass House Mountains, Queensland and my 11 year old is crazy about planting (and eating!) Blueberries. Do you have any recommendations on a good variety for our area.
    Thanks

    1. Post
      Author

      All the varieties we sell are low chill types that would be suited to the Glass House Mountains. I would plant at least a couple of varieties to increase the harvest window and facilitate cross-pollination.
      If I was just planting one variety I would plant Gulf Coast as it is very Self-fertile, hardy and easy to grow. If I was planting a few varieties, I would plant a mix of Gulf Coast, Misty, Sharpblue etc.

  15. Could you please advise “when” you plant blueberries in Australia. I am from Perth and don’t know what time of the year is best to plant blueberries. Thankyou.

    1. Maria, you can plant from about august to november (from when the soil starts to warm from the winter cold). Its best not to plant from about december onwards until about march when it is too hot for young plants. planting in the autumn is ok for southern highbush as their roots will continue to grow through the winter.

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