Truth be told, I like vacuum seeders. They plop down seeds at nice even intervals in a perfect furrow, and then close the furrow with press wheels, creating good seed-soil contact. But vacuum seeders are wicked expensive (I’m living back in Maine now, so I can use words like “wicked”), and they require a tractor to pull them. Sometimes a human-powered seeder is what fits best with the farm budget and needs.
But can push seeders work in an untilled seedbed?
This is one of the questions we are trying to answer in a more-than-anecdotal way. Some of our farmer collaborators have reported both successes and failures with Earthway and Jang push seeders, depending on the conditions. The key components to no-till seeding success are: furrow opening, residue slicing, seed placement, and furrow closing for good seed-soil contact. We have three push seeders to try: A Jang, and Earthway, and a Brazilian seeder, the Knapik.
Can push seeders work in an untilled seedbed?
Untilled seedbed with decomposing forage radish middle and oats in the pathways.
Nate counts the seeds that came out of a seeder over a 2m tarp.
The first thing we did was calibrate our push seeders. Seeds are very hard to count in the ground, but very easy to count on a tarp. All of these push seeders are driven by the front wheel, so rolling them over a known distance on a tarp is a good way to determine how many seeds are actually being dispensed.
Each seed dispensing mechanism is slightly different. The Earthway, for instance, dumps piles of seeds all together, whereas the Jang “singulates” them. Below is the average seeds/ft for each seeder, but this doesn’t mean the seeds were all evenly spaced throughout that distance.
Click for larger image.
After figuring out how many seeds were being dispensed by each seeder, we moved to the field and put some seeds in the ground. I’ll post movies of this in the next post. Generally, we found that the two seeders with the double disk openers (the Jang, and the Knapik) were able to handle the minimal residue in the field, but the Earthway collected a lot of residue on the front and required frequent cleaning. If any of these seeds emerge (fingers crossed!), we’ll post that data soon, too.
