How to Care for Blueberry Plants
Blueberry Quick Facts:
- Latin name: Vaccinium Corymbosum
- Hardiness: Mostly hardy. Suitable for growing across the UK and Ireland with winter protection.
- Pollination: Self-fertile
- Height and spread: 60cm - 2m dependant on variety and pruning
- Flowering: Spring
- Harvesting: Summer
- Difficulty: Moderate
Blueberries are slightly more challenging to grow than some berries, as they have different requirements than your typical hedgerow suspects like blackberries. But the rewards are more than worth it. As well as the antioxidant-packed super fruits, you are also treated to delicate pink and white flowers in spring and a spectacular show in autumn when the leaves turn fiery reds and oranges before dropping.
When you receive your blueberry plant, it is important that you remove it from the outer packaging immediately and store it in a suitable place until you are ready to plant it. In winter, it is a good idea to store the tree in a shed/garage to prevent frost damage.
A big part of growing blueberries successfully is ensuring you have the correct soil. Blueberries will thrive in acidic loamy soil with good drainage and a pH balance of between 4.5 and 5.5m, which can be determined with a pH testing kit. If your soil is not a suitable acidity, you could make it more acidic with the addition of sulphur, but this will need to be done a year in advance and retested to check the pH balance is now appropriate.
If this all seems a little too much like hard work, you could always grow your blueberry bush in a pot, which would allow you to control the plant's micro-climate. Use John Innes Ericaceous Compost or other ericaceous soil to pot blueberries in - other general soils and composts will not be suitable for these lime-hating plants.
If the soil in your garden is suitable and you are planting your blueberry bush in the ground, choose a planting site that gets plenty of sunshine but is sheltered from strong wind and frost. All fruit trees need sunshine to ripen their fruit.
Plant your blueberry bush when it is dormant and the roots are not growing. Either September/October or late February/March as the ground can become frozen solid in intervening months.
An hour before planting your blueberry, water the pot thoroughly. Remove the plant from its container and gently tease out the roots. Prune any that are damaged or broken. Dig a hole roughly three times the width of the trees roots, but no deeper, then plant the tree with the bud union at ground level. Back fill any gaps with the soil mix you removed earlier.
If you have chosen to grow your blueberry plants in pots, and are growing in a peat free ericaceous compost as we suggested above, we advise that you repot your blueberry every twelve months or so, as peat free compost tires quickly.
In the first few years, it is advisable to move the blueberry plant into a larger container so it is not restricted. Look out for the following signs that your blueberry is ready for a more spacious home:
- Does the plant look less healthy than it used to?
- Does it seem to dry out quicker?
- Are there roots growing out of the holes in the bottom of the pots?
Remember to always choose deep pots with drainage holes! Try to repot in the winter months to minimise the risk of damaging the roots.
Some tips for repotting
- Always use a soil or compost designed for ericaceous plants, or with a PH balance of 4.5-5.5.
- The soil around the plants should be slightly moist - water thoroughly an hour before repotting to achieve this.
- Loosen the soil around the edge of the pot and pull the blueberry out by the base of the main stem.
- If you are moving the plant to a bigger pot, add some extra soil into the bottom of the pot before you insert the plant.
- Fill with your chosen soil or compost.
- Water the plant thoroughly, and keep it well watered for several weeks.
Once the plant is fully grown, repotting it may be a big job. Instead, you could think about refreshing the nutrients by replace 30-50% of the compost every other year, so the tree does not exhaust its supply of nutrients.
Blueberries planted in the ground usually require minimal feeding, but if plants are struggling, feed with some ericaceous fertilizer such as Miracle Gro Continuous Release Ericaceous Plant Food.
Feed pot-grown blueberry plants every month in spring and summer with a liquid ericaceous fertiliser, such as Miracle Gro Liquid Ericaceous Plant Food.
Every December, apply sulphate of ammonia to the soil around your blueberry bush according to packet instructions.
Mulching is the term used for the layer of organic material that is placed on top of the soil around your plants, and should be carried out on newly planted blueberry plants grown in the ground as opposed to in pots. It has a whole host of benefits, including keeping the soil moist and nutrient rich throughout summer and discouraging weeds. The best time to do this is in late spring (April-May) or autumn (October).
First, prepare the ground by removing debris and weeds and water the surface of the soil if it is dry, Apply a thin layer of composted or chipped pine bark all around the base of the plant.
Blueberries do not have such heavy water requirements as some fruit plants, and plants growing in the ground may only need watering in very hot or dry weather.
When fruit trees are grown in containers, they will have more restricted access to water than those growing in the garden, so will need watering with greater regularity. But even in this case, blueberry bushes will prefer being kept evenly moist, rather than being deeply watered then allowed to dry out.
Always make sure you water blueberry bushes with rainwater rather than tap water whenever possible.
Blueberries fruit on year-old side branches, so always keep this in mind when pruning - you don’t want to prune all your fruit away! The best time to prune your blueberry is in winter, when the plant is dormant.
No pruning is required in the first two - three years, except to remove dead/dying or crossed branches. Remove fruit buds on younger plants to encourage them to put energy into growing and not fruiting.
After the second year, follow the below simple guide to pruning your blueberry bush:
- First, remove any branches that are dead, diseased or dying.
- Then remove any branches that are growing towards the centre of the tree instead of pointing outwards, as these will not get enough sunlight to produce fruit.
- Remove the smaller twiggy growth from the ends of branches that fruited the previous year, and any branches that will touch the ground when fruit laden.
When pruning a mature blueberry, you may also want to remove some of the oldest main stems, as these are unlikely to be very productive. Any over six years old can be removed - try if possible to develop a system where your plant has a couple of main stems from every year below six.
Fruit and Flowers
Your blueberry will develop creamy white bell-shaped flowers in spring and after a couple of years fruit can be allowed to develop. At this point, it might be an idea to invest in a fruit cage or fruit netting to deter birds. The fruit should be ripe by mid-summer, but not all berries will ripen at once, so several harvests can be gathered from one bush.
Blueberries are deciduous plants that will go into dormancy over winter and lose its leaves - this is normal!
Blueberries are not fully hardy, so it is a good idea to move containerised bushes into an unheated greenhouse or shed (basically somewhere sheltered) when the temperatures begin to drop to protect it from extreme temperatures and frosts.
Protect blueberry bushes planted in the ground from winter weather and delicate early blossom from late spring frosts with horticultural fleece.
Check out our berry plants care guide for information on other types of berries.