Blackberry Calico Virus: A Guide for Home Gardeners
Introduction
Blackberry picking is a cherished tradition in rural areas, but it can be disheartening to find your blackberry plants with yellowing leaves and discolored fruit. These symptoms are often caused by blackberry calico virus (BCV), a common problem in certain blackberry cultivars. While BCV is not harmful to humans, it can affect the appearance and productivity of your blackberry plants.
What is Blackberry Calico Virus?
Blackberry calico virus (BCV) is a widespread virus that belongs to the carlavirus group. It is particularly prevalent in older blackberry plantings, especially in the Pacific Northwest. BCV-infected blackberry plants exhibit distinct symptoms, including:
- Yellow lines and mottling on leaves
- Reddish or bleached leaves
- Distorted or stunted fruit
How is BCV Spread?
BCV is commonly spread through infected cuttings. When new blackberry plants are propagated from infected canes, the virus can be transmitted to the new plants. It is important to use certified, disease-free cuttings to avoid introducing BCV into your garden.
Impact of BCV on Blackberry Plants
While BCV is considered a minor disease, it can still have an impact on the health and appearance of your blackberry plants. Severely affected plants may have reduced fruit production and discolored leaves that can detract from the overall look of your garden.
Management of BCV
There is no cure for BCV, but there are steps you can take to manage the disease and minimize its impact on your blackberry plants:
- Plant Resistant Cultivars: Choose blackberry cultivars that are resistant to BCV, such as ‘Boysenberry’ and ‘Evergreen’.
- Remove Infected Plants: If you have a few BCV-infected plants, you can remove them from your garden to prevent the spread of the virus.
- Avoid Using Infected Cuttings: When propagating new blackberry plants, always use certified, disease-free cuttings.
- Prune Infected Canes: If you notice BCV symptoms on a single cane, you can prune it back to the base of the plant to prevent the virus from spreading.
Edible Landscaping with Blackberries
Blackberries can be used as edible landscaping plants, adding beauty and fruit to your garden. However, BCV can be more severe in edible landscaping situations, as the discolored leaves can detract from the aesthetic appeal of the plants. If you are concerned about BCV, consider planting BCV-resistant cultivars or using other edible landscaping plants that are less susceptible to the disease.
Conclusion
Blackberry calico virus is a common problem in blackberry plants, but it can be managed with proper care and attention. By choosing resistant cultivars, avoiding infected cuttings, and pruning infected canes, you can minimize the impact of BCV on your blackberry plants and enjoy the sweet, juicy berries they produce.