Jian Liu, from Camberwell, has her own website, called Melbourne Foodforest, where she writes articles to help people to develop their own food forests. In early 2022, she published an article about how to grow blueberries. Here she summarises that article.
Blueberries are small compact plants that don’t take up much space. A well-looked after blueberry plant can be productive and reward you with many kilos of fruit each season (up to 9 kg!). They are easier to grow than you think.
This article discusses my 7 rules for growing blueberries.
1. Blueberries must be grown in acidic soil
The easiest way to achieve a low pH is to use a good quality potting mix for acidic plants. The only brand I know that makes a low pH formula is Scott’s Osmocote Roses, Azalea & Gardenia potting mix. As well as a pH of around 5, this mix has everything you need to grow happy blueberries.
The harder option, requiring some arithmetic skills and patience, is to add some elemental sulphur to the soil. In my experience, sulphur acts slowly and it takes at least 2 months before the pH is lowered.
Regardless of which option you go with, I’d recommend also adding some homemade compost which is generally slightly acidic or pH neutral (don’t add lime to your compost!) to bulk out your mix and increase its moisture-holding capacity.
If the pH isn’t right, you will see veining on the leaves of your blueberry leaves, or very pale leaves.
2. Blueberries are best grown in pots or containers
Because blueberries are fussy about having an acidic soil, it’s easier to grow blueberries in a large pot or wine barrel or, if you want to get serious, in a dedicated bed filled with blueberries. This way, you can create the ideal acidic conditions that they thrive in.
Blueberries are shallow rooted plants so grow well in pots. Choose a pot that’s at least 30cm wide and 30cm tall.
3. Grow blueberries in part-shade
Blueberries enjoy some protection from the western afternoon sun and planting blueberries in a full sun spot in summer can turn their leaves crispy.
A benefit of growing blueberries in pots is that in winter, they go dormant and you can simply move your blueberry pots to a shady spot thereby vacating any full-sun winter spot for your winter veggies.
4. Blueberries like moist soil
In summer you will need to water every day or second day to ensure that your blueberry always has moist roots.
5. Mulch is essential
Being shallow rooted, you need to mulch heavily to prevent your blueberries roots drying out. My favourite mulch for blueberries is pine needles as they are mildly acidic( but note that once they decompose they are pH neutral).
6. Grow more than one variety for cross-pollination
When bees cross-pollinate blueberries, you get bigger and tastier fruit.
7. Soil improvement
You should be topping up with compost and manure each season.
Blueberries are best fertilised in late winter or early spring, just after flowering.
If you notice veining or pale leaves, you will likely need to lower the acidity of your soil. We find that our soil pH tends to creep up over time.