Growing blueberries in your home garden is one of the most rewarding garden experiences – who doesn’t love the taste of that plump, sweet, blue fruit? And it’s all the better since you grew those blueberries yourself. Before committing, however, get to know the soil requirements for blueberries, pruning techniques, how to plant them, and how to protect your blueberry bushes from birds.
Blueberries are a perennial deciduous shrub. Once established, they’ll bear fruit for many years – in fact, Highbush Blueberries live as long as 50 years if properly maintained. They’re also attractive as ornamentals with white or pink blossoms in spring and bright, colorful foliage and wood in fall. They can be grown in flat earth garden beds, raised garden beds, as hedges, or as individual specimens.
Blueberry Varieties
There are many varieties of wild blueberries and you might find them growing in your local woods. For the home garden, most cultivars fall under these types: Rabbiteye, Lowbush, Half High, Northern Highbush, and Southern Highbush. Rabbiteye and Southern Highbush are most frequently grown in areas with high heat (such as Georgia, Florida, the Carolinas) and northern Highbush varieties are grown in moderate areas (such as Pennsylvania, New Jersey, Massachusetts, Maine, Oregon). Different varieties produce fruit at different times in the season and there are many cultivars within each variety. Choose the right combination of plants and you’ll have fruit to harvest the entire season.
Northern Highbush Blueberry varieties are grown in Zones 3-8. As a rule, Northern highbush blueberries are self-fertile, but as with other varieties, you’ll get larger and earlier ripening berries if several cultivars are interplanted for cross-pollination.
Lowbush Blueberry varieties are grown in Zones 2-8 and grow wild across the coolest regions of North America. Lowbush varieties are low, straggling, twiggy shrubs, ranging from 6″ – 2′ tall and wide. For best fruit production, plant at least two different varieties. Interesting fact: Lowbush blueberries are fire-tolerant and can increase in number following a forest fire (University Of Maine).
Rabbiteye Blueberry varieties grow in zones 6-9 and shrubs are up to 15 feet tall when mature. They are native to the southern and southeastern U.S. Rabbiteye blueberries require cross-pollination of at least 3 varieties for maximum fruit.
Southern Highbush Blueberry varieties are grown in Zones 7-10. Southern Highbush varieties can be challenging to grow, but they do offer some very early ripening fruit. Mulching with pine bark or pine straw can increase the vigor of southern highbush. Many southern highbush varieties are self-fertile, but planting 2 or more varieties is recommended for improved fruit set.
Most blueberries are self- fertile, but it’s always best to plant multiple cultivars of one variety as cross-pollination encourages larger and more plentiful fruit. Two or more cultivars also mean you’ll have a longer harvest season since they produce fruit at different times.
Blueberries need a loamy, acidic soil
The key to growing blueberries is soil texture and pH. Unlike most plants in the fruit and vegetable patch, blueberries do poorly in a neutral soil of 6.5-7 pH. They require a well-drained, light, sandy loam soil that is high in organic matter and has a pH between 4.5 and 5.5 (acidic). As most soils in North America are neutral or alkaline (around 6.5-7.5), this means that most gardeners will have to add soil amendments like peat moss and elemental sulfur to their garden bed, unless you live in an area where highly acidic soil is the norm.
To determine pH, a soil test is necessary (an online pH test kit is fine). If the soil pH is above 5.5, peat moss should be added (and mixed into the soil at planting time) along with elemental sulfur. How much Sulfur to add depends on how far you need to reduce the pH and the type of soil you have. In any case, apply no more than 3 ounces of Sulfur per plant per season to avoid burning or killing it. Spread the sulfur evenly around the blueberry bushes, a few inches from the base, and lightly work it into the soil. Then water it in. Test the pH again in 6 months to see if the soil needs further treatment. Read about how to acidify your garden soil. You can also read this study on using peat moss and sulfur to quickly lower the soil pH for blueberries.
Avoid planting blueberries in heavy clay soil that drains slowly – standing water or waterlogged soil can damage or drown the roots. To lighten the soil, add lots of organic matter to make it as loamy as possible. Peat moss worked into the garden bed at planting time is highly recommended for its ability to acidify soil and improve drainage. Yard waste, grass clippings, and compost are also excellent organic matter, but these tend to be alkaline and may reduce the acidity of your soil.
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How to plant blueberry bushes
Raised garden beds are the perfect place to plant blueberry shrubs, as the soil can be easily amended and weeded and the water table will be about 14 inches below the soil surface. Fussing with the soil this much may seem like a lot of work, but considering that the plants will bear fruit for 10 years or more if properly tended, it’s a great return on the investment of time.
Where to plant blueberries
Plant blueberry bushes in open areas to encourage airflow around the plants. Poor airflow leaves the bushes vulnerable to spring frost injury and fungal diseases. Blueberries require a minimum of 6 hours of direct sunlight every day (preferably more) for bearing fruit. If shaded by trees, fences or walls, fruiting will be reduced.
When to plant blueberries
Plant 2-year-old (or more) blueberry shrubs in fall or early spring. Shrubs should be planted 4-5 feet apart (rabbiteye blueberries at 6 feet apart). When the bushes are all in one raised garden bed, or planted in a line in a flat earth garden, monitoring and adjusting the soil pH and weeding will be easier. If planting multiple rows, the rows should be 10 feet apart. Set the plants at the height they were in the containers – if planted too deep the plants may smother.
Prune blueberries for more fruit
After planting, firm the soil around the roots with your hands to remove air pockets. Then, prune shrubs back by 30% to encourage new growth (see how to prune blueberries here). The goal of pruning is to remove old growth and keep the new growth at the base of the plant (referred to as “whips”). Blueberries should be pruned every winter to reinvigorate the plant and increase fruit production.
Remove flower blossoms the first season
Next, remove any flower blossoms to discourage all fruit development the first year, and again the following year (I know, removing the fruit buds on purpose is nearly impossible for most of us, but trust me, you need to do this). This encourages strong growth and a shrub that will produce fruit for many years. Do not fertilize the first season.
Mulch blueberries
Blueberry roots grow close to the surface, so keep a 4-foot area around the plants free of weeds. Be careful with cultivation tools so as not to damage the roots. To conserve moisture, control weeds, and keep the roots cool, add a 6-inch layer of organic mulch like peat moss or pine bark around each shrub.
Fertilizing Blueberries
Do not fertilize blueberries in the first year. In general, blueberries have a lower demand for nutrients than other fruit crops. They usually only require small amounts, if any, of supplemental fertilizer, and usually, only Nitrogen – most soils contain sufficient potassium, phosphorous and trace minerals. But an acidic pH is a necessity so the blueberries can utilize the nutrients present in the soil. If it’s too alkaline, the roots cannot use the nutrients present.
If fertilizer needs to be added, apply to established plants early in the season when green shoots are growing. But beware how much Nitrogen fertilizer you add, as too much can damage the plants and even kill them – go easy, they don’t need much if any. Excessive fertilizer rates can reduce blueberry vigor, yields and hardiness – it also wastes money and pollutes water when the fertilizer runs off, unused. Recommended organic fertilizers for blueberries are Blood Meal, Soy Meal, Fish Meal, Alfalfa Meal or Feather Meal.
Watering Blueberries
Blueberries have a shallow root system close to the surface, making them easily susceptible to injury from drought. That’s why they need frequent watering. The soil should have consistent water but it must never be waterlogged – it should drain quickly. Young plants need roughly 1-inch of water each week and should be irrigated in the absence of rainfall. Established blueberries need 1.5″ – 3″ of water each week.
For best fruit production, water the plants consistently from blossom through harvest. After harvest, fruit bud formation begins right away and lasts until August, so water is critical at this time as well (so water regularly from April through Labor Day). Concentrate water on the root zones, not overhead, to avoid fungal diseases – a drip irrigation system is ideal. Only water to supplement rainfall and avoid overwatering so the soil does not become waterlogged.
Care for mature Blueberry plants
- Keep them mulched to a depth of 6 inches around the root zone.
- Shrubs should be pruned every winter.
- If there is a need to fertilize blueberries, they only require Nitrogen for top growth. There is sufficient Potassium and Phosphorous in most soils.
- Lack of growth and susceptibility to diseases is frequently a pH problem in blueberries, not a lack of nutrients. It’s the acidity level of the soil that allows the blueberry roots to take up nutrients and utilize them and adding more fertilizer won’t make a bit of difference if pH is the problem.
- Berries ripen over a 2-5 week period, so use bird netting to protect your blueberries from birds and squirrels who’ll steal them quickly just days before you pick them (this made me very sad one year). Don’t drape the netting over the bushes as it makes harvesting impossible. I drape the netting from wooden stakes above the tops of the bushes and then use rocks and bricks to seal it to the ground (animals will get in between U-pins, so they’re useless. The bird netting needs to be easy enough to unwrap when it’s time to pick your rewards throughout the season.
Sources: Cornell University, Organic Production and IPM Guide for Blueberries; Mississippi State University Extension, What varieties of blueberries should be grown?; Oregon State University Extension, Growing Blueberries in Your Home Garden; Penn State University Extension, Blueberry Variety Selection in the Home Fruit Planting; University of Georgia Extension, Home Garden Blueberries.
We garden in Pennsylvania, United States, zone 6B. Much of the info we share is based on gardening in our temperate area. But many of the flowers, vegetables, and fruit we write about can be grown in soil other than ours (clay) and significantly different weather conditions and elevations. You might need to choose specific varieties for your region, modify your garden, add soil amendments, or adjust the soil pH to match our results. Please check your local university extension website for specifics for your area.
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