Try mowing 2 or 3 times in the summer, then the herbicide in September.
A neighbor destroyed a patch by mowing, only, but I don't recall how many
years that took.
----Original Message Follows----
From: Jim Fruth <>
To: <nafex@>
Subject: [NAFEX] Eradicating Blackberry Plants
Date: Sat, 17 Dec 2005 07:44:46 -0600
When I eradicate a blackberry patch, I, first, mow them down to the
ground. Then, when the sprouts are 4" to 6" tall, I give them a good dose
of Round-Up. I usually need to repeat that two to three times then wait a
season to be sure I killed them all. I must keep after them because if I
allow too much time between spraying, they become resistant to Round-Up
necessitating more drastic measures.