
Blackberries are a gardener's delight, known for their juicy, sweet berries and ease of cultivation. With varieties like erect thorny, erect thornless, and trailing thornless, they offer diverse options for any garden. While generally easy to grow, they do require full sun, fertile soil, and regular pruning to thrive. Their resilience and long lifespan make them a rewarding addition to any garden.
- Common Names: Dewberry, Northern Blackberry
- Scientific Name: Rubus fruticosus
- Plant Type: Perennial, fruit
- Plant Height: 3-10 feet
- Growing Difficulty: Easy
- Growing Time: Second-year canes produce fruit
- Bloom Time: Spring, Summer
- Temperature: Heat tolerant
- Hardiness Zone: 4-10 (Find your hardiness zone here)
- Sunlight: Full Sun
- Soil pH: 5.6-6.5
- Watering Frequency: Moderate amounts of water
- Plant Spacing: 5 to 6 feet apart
Different Methods to Grow Blackberries
Erect Thorny Blackberries
These blackberries have self-supporting canes that grow upright, making them easy to manage without additional structures.
- Pros: No need for trellising, simpler setup.
- Cons: Thorns can make harvesting and maintenance challenging.
Trailing Thornless Blackberries
These varieties have long canes that require trellising or support structures to grow properly, but are easier to handle due to the absence of thorns.
- Pros: Higher yields with proper trellising, easier to handle.
- Cons: Requires a trellis or support structure, more labor-intensive.
Semi-Erect Blackberries
These blackberries have a growth habit that is between erect and trailing, offering versatility in how they can be grown.
- Pros: Can be grown with or without support, versatile.
- Cons: May require some support for optimal growth, moderate maintenance.
Ideal Soil and Location Requirements
For optimal growth, blackberries need loamy, well-drained soil enriched with organic matter. The ideal location is one that receives full sun, ensuring at least six hours of direct sunlight daily. Avoid planting near wild blackberries to prevent disease.
When to Plant Blackberries
Blackberries should be planted in early spring while the canes are dormant. In very cold areas, planting can be delayed until after the last frost date to avoid low temperatures that could harm the plants. Late fall is also an option, but early spring is generally preferred.
Growing Blackberries Outdoors
Planting blackberries in early spring while the canes are dormant is the best method for growing them outdoors. This timing allows the plants to establish roots before the growing season begins, making it easier for them to thrive.
- Choose the right location. Select a site that receives full sun for at least six hours a day. Ensure the soil is loamy, well-drained, and slightly acidic with a pH of 5.6 to 6.5.
- Prepare the soil. Amend the soil with organic matter to improve fertility and drainage. Avoid planting near wild blackberries to prevent disease.
- Space the plants. For semi-erect cultivars, space plants 5-6 feet apart. Erect cultivars should be spaced 3 feet apart, and trailing varieties 5-8 feet apart. Rows should be about 8 feet apart.
- Plant the blackberries. Dig holes that are wide enough to accommodate the root system. Plant the canes 1-2 inches below the soil surface. Firm the soil around the roots and water thoroughly.
- Install support structures. For trailing varieties, set up a trellis or support structure to train the canes. This helps in managing the growth and makes harvesting easier.
- Water regularly. Ensure the plants receive about 1 inch of water per week, especially during the growing and ripening seasons. Avoid waterlogging the soil.
- Mulch the plants. Apply a 1-2 inch layer of mulch around the base of the plants to retain moisture and suppress weeds.
- Fertilize in early spring. Use a balanced fertilizer such as 10-10-10 or 16-16-8 to promote healthy growth. Apply another round of fertilizer post-harvest.
- Prune the canes. In early spring, tip-prune new canes to about 3 feet. After harvest, cut second-year fruiting canes to ground level. Remove any winter-damaged canes and thin to four or five of the strongest canes per foot.
- Harvest the berries. Pick fully black, plump berries every couple of days during the ripening season. Gently pluck the berries, leaving the central plug inside. Refrigerate immediately to preserve freshness.
Growing Blackberries Indoors
Growing blackberries indoors is not typically recommended due to their need for full sun and ample space. However, if you have a sunny indoor area and are willing to provide the necessary care, it is possible to grow them in pots. Here’s a step-by-step guide for home gardeners:
- Select a large pot. Choose a container that is at least 2 feet wide and has good drainage.
- Use well-draining soil. Fill the pot with slightly acidic, loamy soil with a pH of 5.6-6.5. Amend with organic matter if necessary.
- Plant in early spring. Plant the blackberry canes while they are dormant, about 1-2 inches below the soil surface.
- Place in full sun. Ensure the pot is in a location that receives at least six hours of direct sunlight daily.
- Water regularly. Provide about 1 inch of water per week, ensuring the soil remains moist but not waterlogged.
- Fertilize in early spring. Use a balanced fertilizer such as 10-10-10 to promote healthy growth. Apply another round post-harvest.
- Install support structures. Use a small trellis or stakes to support the canes as they grow.
- Prune the canes. In early spring, tip-prune new canes to about 3 feet. After harvest, cut second-year fruiting canes to ground level.
- Mulch the plants. Apply a 1-2 inch layer of mulch around the base to retain moisture and suppress weeds.
- Harvest the berries. Pick fully black, plump berries every couple of days during the ripening season. Refrigerate immediately to preserve freshness.
Blackberries are self-pollinating, so you will not need multiple plants for fruit production. Bees and other insects will assist in pollination.
Caring for Blackberries
- Watering: Ensure your blackberry plants receive about one inch of water per week. During hot weather, you might need to increase the frequency to keep the soil consistently moist but not waterlogged.
- Fertilizing: Apply a balanced fertilizer, such as 10-10-10, in early spring when the plants emerge from dormancy. A second application post-harvest in late summer or fall will help maintain plant health.
- Mulching: Keep a 1-2 inch layer of mulch around the base of the plants. This helps retain moisture, suppress weeds, and regulate soil temperature.
- Pest Management: Common pests like raspberry borers and fruit worms can affect blackberries. Keep plants healthy and vigorous to reduce pest attraction. Remove and destroy any plants showing signs of viral diseases.
- Harvesting: Pick fully black, plump berries every couple of days during the ripening season. Harvest during the cooler parts of the day and refrigerate immediately to preserve freshness.
Common Challenges With Blackberries
Blackberries are a resilient and easy-to-grow plant, making them a favorite among gardeners. They are perennials with roots that survive year after year, requiring minimal maintenance once established. With proper care, blackberries can thrive in a variety of conditions, from full sun to partial shade, and in different soil types. Their long lifespan, often ranging from 15 to 40 years, ensures that a well-maintained blackberry bush can provide bountiful harvests for decades.
However, growing blackberries does come with its challenges. Common issues include diseases like anthracnose and raspberry bushy dwarf virus, as well as pests such as raspberry cane borers and stink bugs. Proper pruning is essential to avoid a tangled mess and ensure a good fruit yield. Additionally, blackberries require consistent moisture, especially during the growing and ripening seasons, but they do not fare well in waterlogged soils. Despite these challenges, with a bit of attention and care, blackberries can be a rewarding addition to any garden.
Safety of Blackberries for Pets
Blackberries are generally safe for cats, dogs, and other pets. However, if you suspect your pet has ingested a large amount and is showing signs of distress, contact the ASPCA 24-hour hotline immediately.
Frequently Asked Questions
How do I transplant mature blackberry bushes?
Transplanting mature blackberry bushes is best done in early spring while the plants are still dormant. Dig up the root ball with as much soil as possible, replant immediately in a prepared site, and water thoroughly to help the plant establish.
Why are my thornless blackberries sour?
Thornless blackberries can be sour if picked too early. Wait until the berries are fully black and slightly dull in color before harvesting. This ensures they have reached peak sweetness and flavor.
What are the brown spots on my blackberries?
Brown spots on blackberries are often leftover bloom remnants and do not affect the fruit's quality. If the spots are soft or moldy, it could indicate a fungal issue, and affected berries should be removed to prevent spread.
Is it okay to plant blackberries near raspberries?
It is generally not recommended to plant blackberries near raspberries. Both plants are susceptible to similar diseases, and close proximity can increase the risk of disease transmission. Plant them in separate areas to maintain plant health.