Published on 24/07/2026
And the two are related, as he explains, because the relatively cool growing environment means that the maize crop’s canopy remains open longer than in warmer regions:
“The canopy doesn’t shut early enough, so weeds obviously start to come through.”
It’s now eight years since Mead and his dad Andy switched from keeping a dairy herd to concentrating on growing maize on their third-generation family farm near Hāwera.
That’s been a very successful change overall, but he says the weed situation has been getting progressively worse.
In 2024, the young crop was ‘just filthy, covered in weeds’.
Luckily the Meads had done some trial work with Sharpen that gave them an indication of how well it could fit into their programme.
So in 2025, they switched to using Sharpen for their pre-emergence weed control for the first time and found it produced a ‘massive improvement’.
Robert Mead says that they were mainly targeting bindweed as well as ‘all the other nasties that come with it’.
Using Sharpen and acetochlor instead of atrazine and acetochlor kept all the weeds at bay much more effectively.
The maize was sown on 20 October. Eight weeks later, on 15 December, Andy Mead says there were a lot less weeds in the crop than at the same stage the year before.
“Tiny seedlings,” Robert Mead chips in, “just a few weeds here and there, nothing too major.”
He goes on to describe the big pay-off in cost and time savings that much better pre-emergent weed control delivered.
“The post-emergent spraying was kept to a minimum: 30 hectares compared to at least 100 the year before.”
In challenging growing conditions where early weed competition has been an increasing problem, Sharpen helped to keep the crop very clean through establishment and massively reduce the need for follow-up spraying.
No wonder Robert describes its performance as outstanding.