This week in the garden I have been admiring my blueberry plant that I have growing in a 35-litre pot.
It is looking spectacular, with a combination of blue-sheened leaves and some that are orange in colour from the cooler winter months. It could probably do with a feed which I will do this week. A mixture of Tui Acid Fertiliser and Nova Tec will deliver what it needs. It currently has masses of flowers on it, which means I am destined for a good harvest of blueberries come summer. Blueberries are not the quickest growing of plants to establish and this one is now coming up to its fourth year in its pot and is just starting to come into its own.
Blueberries are a fashionable item in the garden and on the plate. Thoughts of blueberry muffins, smoothies with blueberries, and blueberries and ice cream all evoke senses that make one want to go looking through the fridge for dessert.
If the thought of all the delicious dishes blueberries can be a part of don't tempt your taste buds, then maybe the health properties will make you an advocate for this intriguing berry. Blueberries are both vitamin rich and high in antioxidants, with properties that are beneficial in fighting heart disease, aiding against ageing skin and boosting brain development.
In New Zealand, blueberries are among the five most common berry fruit grown, whilst in the US they are reputedly ranked second to strawberries as the most popular berry to consume. Though native to North America, they also grow well here in New Zealand. A quick internet search showed that commercially in New Zealand there are blueberry orchards in Canterbury, Waikato, Kerikeri, Bay of Plenty and, I'm sure, many other localities. A number of varieties have been bred in New Zealand specifically for our climate and conditions.
As many are exploring productivity in the home garden and healthy eating, as well as the budget-slashing benefits of seasonal eating from our own gardens, let's look at how we can add these must-have berries to our harvest here in Whanganui.
When you are planning to grow any new plant, it is worth first establishing the basic essentials for the plant in question: the environmental requirements (shelter/light/space), soil preferences, moisture tolerances/needs and the optimal nutrient levels.
Blueberry plants will remain fruitful for many years so carefully plan your spot to grow them.
When making a site selection for blueberry plants, taking the following points into consideration will give the best results.
Like almost all fruit, blueberry plants will perform best in full sun. They are fairly indifferent to wind, though exposure to a strong prevailing wind will limit growth. Blueberry plants should be allowed space of about 1m to 1.5m to grow individually as bushes. They can be grown in rows and if planted closer together will form a hedge. Some densely planted rows will have plants as close as 60cm-80cm. There are some size differences between varieties.
Blueberries have both female and male parts on the same flowers; however, most will not pollinate themselves. So having two different varieties planted in relative proximity (within 20m of each other) will ensure the bees share the pollen around and will have the best possible crop. There are a few self-fertile varieties – check the label when purchasing plants.
The soil needs to drain well, whilst still providing moisture. If your soil tends to retain water or gets boggy, then building elevated beds would be an advantage. This will eliminate water logging. Raised beds are also a good option where natural soil quality is poor.
Because they prefer an acidic soil with a pH of 4.5-5.5, they are ideally suited to growing in the parts of Springvale and Mosston which have naturally occurring peat soils though, as aforementioned, drainage may need to be addressed. But don't be perturbed if your soil is not naturally peat. Soils can be enhanced with the addition of Yates Hauraki Gold Peat. This can be liberally mixed in with the existing soil when planting.
When fertilising, use an acid fertiliser, the same as is used for rhododendrons, camellias and daphne. For established plants, a mulch of peat around the plants in November or December is advantageous, helping to limit weed growth and conserve moisture during the summer months, as well as providing an acidic conditioning to the soil.
Caring for your new blueberry patch is not difficult, but particular attention to certain needs will assure you of fresh or frozen blueberries all year round when you produce a bountiful crop. Here are some essential tips for nurturing along your plants.
Like citrus trees, the flowers should be removed from your blueberry bushes for the first couple of years. This gets a good-sized bush established. Once they are up to a reasonable size they can be left to fruit, but should then be pruned every July. Blueberries fruit on second-year wood. Prune by first removing any diseased or dead wood, then any low spreading branches as it is best to encourage more upright growth. It is good practice to remove some older branches each year to encourage newer ones to develop. Some shortening of growing tips will help increase the size of berries.
No matter what soil your blueberry patch is in, come September, December and February, apply an acid fertiliser. This will maintain good plant growth and health, and thus promote good yields of berries. Be careful not to apply too much at once, as it simply washes away before it is of use to the plant – little and often is most beneficial.
Blueberry plants are shallow rooted, requiring regular watering during the drier summer months. Regular watering is particularly important to establish the plants in the first couple of years.
If you're short on space, blueberries can be grown in pots. Mix an acid fertiliser through the potting mix when planting and use it as a supplementary food three times a year. When growing in pots, it is particularly important that they are watered regularly. The biggest failure of plants growing in pots is the lack of water so, if you're going away, make a deal with your neighbour or install a simple watering system with a timer.
Now you are your own resident specialist in blueberry growing. No doubt you already have in your mind's eye the perfect spot and are perhaps currently imagining yourself out there with bowl in hand, collecting great plump berries. But before you start, your last remaining undertaking is to choose your variety. Variety selection is an important factor. Different varieties perform better in different climates, so you want to choose from those suited to Whanganui.
By growing a range of varieties, fruit can be harvested from November to April. There are three main types of blueberries in New Zealand.
Northern High Bush are deciduous plants which are later flowering so are great for areas which can get late spring frosts such as Ohakune, Taihape, Raetihi, Central Otago etc. Most are self-fertile but varieties will produce a larger crop if planted with a second Northern High Bush variety. Good varieties for these cooler areas are Blueberry Muffin and Blueberry Reka.
Rabbiteye varieties are evergreen plants that do really well in Whanganui and tend to carry on fruiting later into early autumn. You need to plant two Rabbiteye varieties to ensure cross pollination and fruiting. Good varieties of these for Whanganui include Blue Magic, Blue Dawn, Maru, Rahi, Sapphire Blue, Blast, Tif Blue and Powder Blue.
As a general rule, planting two plants for each blueberry lover in your household will give you enough berries to use.
So, you're well equipped to give it a go. Get started now in your home garden and grow yourself a bountiful harvest of delectable anti-ageing, heart disease reducing, brain improving desert.
Have a good week.
• Gareth Carter is general manager of Springvale Garden Centre.