Weeds Around Blackberries

Site Preparation

• Properly preparing the site before planting blackberry bushes can help reduce the number of weeds that grow as well as optimize soil conditions. Select the site one season before planting the bushes and plant a cover crop such as wheat or rye. Plowing these mature plants under will increase the organic material in the soil, raise the level of available nutrients and discourage weed growth. Selecting a fast-growing cover crop may allow enough time for two plantings, and destroying weeds that show up during this phase will prevent seeds from taking root and growing.

Preventing Weeds

• An application of mulch between the blackberry bushes but not up to the roots of the plants can help discourage weed growth by blocking the sunlight that seeds need to germinate. An application of sod will work in a similar way. For large crops of blackberries, it can be useful to plant another crop that does not directly compete with the bushes. Planting grasses throughout the season will help use up some of the nutrients left behind by the blackberry bushes that weeds could otherwise use to grow. Grasses are not high-maintenance enough to compete with the bushes and will die before taking anything but the leftover nutrients. Another option is to plant a crop such as oats after the berries have been harvested. This will use up extra nutrients in a similar way and prepare the soil for the next spring.

Removing Weeds

• When weeds appear the most efficient way to remove them is to pull them out by hand. This will prevent the blackberry roots from being damaged by shovels or other tools and will not expose the bushes to herbicides. Healthy blackberry bushes often need to be pruned, and doing so will not only increase the air circulation and the sunlight that reaches the interior of the plants, but will make pulling the roots around the base of the bushes easier.

Dangers of Weeds

• If weeds are allowed to grow around the blackberry bushes, they soon will begin to compete with the more desirable plants. Blackberries need sufficient nutrients to grow healthy, tasty fruits, and weeds will take these nutrients away. The weeds also will absorb much-needed water, and crop size and quality can be greatly diminished. When weeds are allowed to overrun the bushes, they can also attract other pests. Insects may be attracted to the weeds and stay for the blossoming and fruiting of the blackberry bushes. Thick mats of weeds also will encourage continuous moisture and dampness that can result in the development of mold and fungal infections.