Blackberries are an edible fruit from the Rubus genus, and blackberry plants are just one type of flowering plant from the Rosaceae family. Blackberries are dark fruits made of small drupelets that grow on thornless or pricked canes. Although blackberry plants are easy to grow, common blackberry problems threaten the growth of blackberry bushes.
Blackberry plants are perennial plants that grow biennial canes from their root system. The first year of growth for blackberry bushes involves developing primocanes that produce leaves but no flowers. The following year these canes become floricanes with buds that produce lateral growths. Flowers bloom from these laterals, allowing these plants to pollinate and grow blackberry drupelets.
As rewarding as blackberry bushes are for home growers, these are various problems you may encounter when caring for fruiting canes. Common issues for blackberry bushes involve diseases that lead to defoliation and pests that threaten the life of your plant and blackberry yields.
Problems When Growing Blackberries
During the growing season, blackberry bushes may become affected by various diseases from fungal or bacterial sources. These diseases affect the leaves, canes, and even the fruit of the blackberry plant.
Insect pests are another issue for blackberry bushes as they damage the foliage, and blackberry seeds need to be protected from insect activity. Bushes with severe damage may never produce fruit and cause gardeners to remove infected plants or canes to save the rest of their blackberry plant.
Fungal Blackberry Diseases
Fungal infections in gardens are not uncommon because wind spreads fungi, allowing it to infect plants quickly. Depending on the fungus, the infection targets your blackberry plant’s leaves, canes, or fruit.
Anthracnose is one disease that affects the canes of blackberry plants and causes them to develop lesions. Because this fungus overwinters in infected canes, it’s best to prune diseased canes to prevent the spread.
Another common fungal disease is cane blight, which results in cankers forming on the canes of your bushes. This fungus overwinters in old canes and debris left behind after pruning. Be careful when transplanting blackberry bushes into soil, as new plants can be infected by stems left over in the ground. To avoid the risk of cankers, schedule pruning during periods of dry weather to prevent rainfall from carrying fungus spores to your plant.
Blackberry Problems from Bacterial Diseases
Crown gall is a common disease that infects flowering plants and causes swelling growth on the plant. These galls form on canes above ground level but may develop on the root system.
Plants become infected with crown gall once the bacterium enters the plant, typically through a wound caused by pruning or weather damage. Because there is no cure for crown gall, destroying infected plants is the best option to prevent it from spreading to other plants.
To avoid further issues with crown gall, practice crop rotation and avoid planting seeds or starts in areas affected by crown gall in the past three years.
Why are My Blackberry Leaves Turning Orange?
If your plant’s new growth is weak and you see blackberry leaves turning orange, these are symptoms of a fungal infection known as orange rust. Once infected by the fungus, leaves develop a pale color before pustules grow on the underside of the leaf.
These bumps become orange and powdery as they spread over the leaf surface, eventually causing leaves to fall off the plant.
This fungus overwinters inside the brambles of wild blackberry plants. To manage the spread of orange rust, prune and burn infected canes after harvest. Another method to prevent orange rust from spreading to nearby plants is to treat the orange rust with fungicides. There are different types of blackberry bush needs, so be sure to learn about the type of blackberry bush that you have.
Dealing with Bugs in Blackberries
Insect pests are a severe threat to your garden as bugs in blackberries lead to plant damage if infestations are left to feed on the leaves and canes of your blackberry bush. Although insect damage is not typically fatal to blackberry plants, finding bugs in blackberries leads to defoliation and a reduced yield.
Common Blackberry Pests
Japanese beetles are a common pest on the leaves of blackberry plants. Adult beetles chew on foliage that becomes skeletonized; however, because of their size, picking beetles off your plants is an effective method for managing their numbers.
Leafrollers are a pest that leaves distinct signs of activity on host plants. Mature larvae use webbing to string together leaves, causing them to fold or roll over on themselves. The larvae feed inside the safety of the rolled leaf.
Burrowing insects, like the cane borer, create tunnels inside the canes of your blackberry bush. Cane borer activity in canes causes galls, and cane borers overwinter inside these growths. Remove canes with galls to destroy larvae and treat your bushes with a homemade insecticide to manage pest activity.
Combine dish soap with water in your sprayer to emulsify the water, and add the cold-pressed neem oil. Spray your bushes at dawn or dusk to avoid targeting beneficial insects while treating the canes and leaves for any bugs in blackberries.
Understanding the problems that blackberries face while growing blackberry bushes is vital. We hope you can now identify threats to your blackberry bushes to save your plants before it affects your blackberry fruit yield.
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