How to Kill Blackberry Plants

There's something very satisfyingly primal about picking blackberries off the vine in your own backyard to eat in hand or bake a luscious cobbler. Left unchecked, blackberry bushes can expand rapidly and make your yard an impenetrable mass of brambles. Blackberry bushes are a tenacious adversary and killing them isn't easy. You can try mowing, bulldozing, digging them out by hand, or even burning them out, but they'll come back. In fact, they usually come back thicker and better.

Difficulty: Challenging

Instructions

Things You'll Need:

• Chainsaw, sickle or heavy-duty weed whacker
• Rototiller
• Weed killer
• Newspapers or dark covering
• Gardening gloves
• Goggles
• Trash bags

Non-chemical methods that work

1. Cut down as much of the above-ground plant as possible with a sickle, chainsaw or weed whacker.

2. Collect and dispose of all plant materials.

3. Rototill the entire spot repeatedly until the roots are so decimated that they cannot regenerate. This method will take time and diligence, but if you don't want to use chemicals, this is the way to go.

4. Cover the entire growth area with at least four layers of newspaper or with a dark cloth to help ensure that the blackberry plants cannot re-sprout.

Using Herbicides

5. Using herbicides is a smart way to clear your yard of blackberry brambles. Spraying in the winter when the bushes are inactive is ineffectual. The best time of year to spray is early spring when the plants are just starting to green, before the berries ripen.

6. Dispose of as much of the dead plant material as possible. Any bit left alive will root and grow.

7. The next year, look for new sprouts and spray them while they are still young, and repeat as necessary until the plant is gone.

What NOT to do

8. Mowing is probably the worst thing you can do. That won't touch the roots, so the original plants will grow back, and it will also scatter bits of stem, which will sprout in new areas.

9. Bulldozing won't work, either; you'll just spread the growth area and stimulate new growth.

10. Don't try to pull them out by hand. The roots run horizontally underground, so there's no way you could get them all, and it would be painful and difficult to try.

11. Burning will only encourage new growth along the rhizomes, which are horizontal underground roots.

Tips & Warnings

• Wear goggles and heavy work gloves to protect your eyes and hands from splinters, thorns and flying debris. Read the label on the weed or brush killer and use the right concentration. Using more does not make the product stronger, so you'll get the exactly same effect and it will cost more. Spraying during drought conditions won't work. The blackberry bushes effectively will be dormant, so the poison will not circulate and the spray won't kill them.
• Use caution when spraying chemical plant killers. They do not discriminate between plants and will kill every plant they come in contact with, including grass. Never spray weed killer on plants when blackberries growing; blackberries eaten after the poison is absorbed in the roots could be fatal for humans, pets or wild animals.

References

• Getting rid of Blackberry Brambles
• Nonchemical Methods for Removing Unwanted Blackberry Plants