Healthy soil and sustainable growing

[Harvey Ussery <harvey@themodernhomestead.us>]

Thanks for posting this, Paul. I've been using radishes as cover crop 
the last two growing seasons, found a lot of useful info.

(Note: More comments interspersed below.)



> University tests show radishes good choice for cover crops
> http://www.theprairiestar.com/articles/2009/10/12/ag_news/farm_and_field/field1.txt
>
> By TERRI ADAMS, The Prairie Star
> Friday, October 9, 2009 3:34 PM MDT
> Radish tap roots can be 2 to 3 inches in diameter, as seen in this photo, and extended almost 2 feet into the ground. That root system breaks up soil compaction and increases deep water penetration and storage. Photo courtesy of Steve Groff.  
>   

It looks in the photo as if Groff's tiller radishes are developed out of 
daikon types. I've used daikon for this purpose on a limited basis, but 
seed in that quantity is expensive. This season I've been using oilseed 
radishes for cover crops--seed from FEDCO in Maine. Don't know if the 
roots get as big as daikon types, will be checking that as the main fall 
plantings mature. But the article is right--very easy cover crop.


> Tests at five different universities show radishes offer more soil benefit 
> and require less work from the producer than all other standard cover crops.
>   

One benefit not mentioned in the article: I've read in many sources that 
radishes (this can be true of other crucifers as well) have a 
"cleansing" effect on the soil, i.e. help discourage soil pathogens 
including fungal.


> According to Steve Groff, partner at Green Tillage and CEO of Steve Groff 
> SEEDS, LLC., radishes are gaining the attention of farmers around the 
> country, and deservedly so. . . .
>
> “We were able to get some seed and started propagating it and expanding it.” 
> When they had enough seed to sell, they began marketing Tillage Radishes. . . 
> .
>
> As farmers hear and see the results they are starting to plant radishes in 
> their own fields, either as a stand alone cover crop or with cover-crop mixes.
>
> “That's the next generation of this -cover-crop mixes or cover-crop 
> cocktails,” said Groff. “It's not a fad; it's a trend and radishes are on the 
> leading edge of that right now. Producers are saying radishes go in every 
> mix.”
>   

I have a beautiful stand of mixed cover that includes lots of oilseed 
radish--along with several small grains, peas, rape. I'll soon be 
turning in my mixed tiller flock (chickens, ducks, geese) to eat that 
smorgasbord and tilling it in.


> “Even though they are a cool season crop, you can plant them with warm season 
> mixes as early as July,” he said. “They stay in the canopy until September; 
> then they really start to go.” He said radishes seem to thrive in cold, 
> dryland areas like those found on the Northern Plains.
>
> Groff agreed. “They really like the cooler weather,” he said.
>
> Radishes also help improve water penetration. Most plants send out fine, 
> hair-like root systems. According to Miller, “the radish gets a very deep tap 
> root. In 45-60 days you can get a root that is 2 to 3 inches in diameter. The 
> root tapers off at about a foot and a half and then sends out a very fine tap 
> root that can go down to 5 feet,” Miller said.
>
> That opens large holes in hard, dry soil; allowing for optimum and deep water 
> penetration and storage and helps aid in the aeration of the soil, breaking 
> apart compaction.
>
> “They are the best plant I've seen for going through a hard layer of soil. 
> Most other roots will hit a hard layer and then turn and go horizontal. Not 
> radishes. They are aggressive that way. They will find a crevice and keep 
> growing down.”
>   

I love this idea of tap-rooted cover crops serving to "till" the soil by 
opening up even bigger channels (than feeder roots) in the soil.

BTW, the article also doesn't mention another benefit: Cover crops with 
roots that go deep like this "mine" the lower subsoil of minerals, then 
make them available to more shallow rooted plants when they die and 
decompose.


> Groff said that those thick, long roots are also unique for another reason.
>
> They scavenge all the nitrogen they can find, either from the soil or 
> chemical applications, and store it in their root system until spring time.
>
> Then, when it begins to thaw, the roots decompose. As they decompose they 
> release all that nitrogen back into the soil, loading the soil with the vital 
> nutrient just in time for the next season.
>
> “A lot of these other cover crops, like rye grasses, when they decompose the 
> nitrogen is used up by the microbes and they are only able to give it back 
> incrementally. Not radishes. They give it all back,” Groff explained. “We say it's 
> like a bank account. You invest nitrogen in it and then you get it all back in the 
> spring with interest. The interest is that the radishes have also broken up and 
> opened the soil, provided organic matter, and will increase crop yield."     
> In multiple university tests those crop yield increases have run from eight 
> bushels per acre to 41 bushels an acre in one corn test.
>   

Most interesting. I knew their role for "mopping up" excess nitrogen 
(which is why I planted them this fall in beds I had just heavily 
composted in preparation for next spring), but wasn't aware of the 
"timed release" angle.


> For colder climates, Groff says producers should consider planting radishes 
> as a cover crop from mid July to the beginning of September. Producers should 
> try to plant them no later than four weeks before the first killing frost. . 
> . .
>
> Once seeded, radishes germinate rapidly. . . .
>
> Once up, radishes grow rapidly, covering the area and suppressing weeds. They 
> will continue to grow until a hard frost.
>
> “Even if you have nights that get down into the teens, they're fine if the 
> days warm up to the 50s and 60s. They like cool weather so it takes several 
> nights down in the teens to stop them,” he said.
>
> Once stopped, radishes overwinter in the soil, reducing wind erosion and 
> trapping needed snow. In the spring, as the ground begins to thaw, radishes 
> decompose on their own. No need to spray or disc the ground.
>
> Miller said they decompose rapidly. “This is all done no-tillage,” he said. 
> “You seed directly into the crop residue in the fall and in the spring they 
> decompose on their own. You don't have to work to get rid of them. We call 
> them the ripper crop because they eliminate tillage.”
>   

Just imagine the amount of soil loosening you get when roots this 
big/long turn to mush.


> Miller said there are many benefits. Cattle can graze radish tops from winter 
> fields.
>   

I've been cutting the growing tops for green forage for my layer flock. 
They scarf them up.

Am also growing them in the overwinter greenhouse for simultaneous soil 
improvement there and winter greenery for the fowl.


> Radishes also “help feed the soil and get it in balance. It's a great 
> fertility program and you get a tremendous crop response the following year,” 
> he said.
>
> Producers who are interested in learning more about Tillage Radishes can go to     http://customers.clarycommunications.com/m/b7aGd05OJnKYjdebIGj1RC4YDzgnkN18cXqjTCL98Qr7narocg or www.tillageradish.com. 
>   

Thanks again, Paul!

~Harvey

--
Harvey in northern Virginia
www.themodernhomestead.us

If you grew as fast as a commercial broiler chicken, you'd weigh 349 pounds 
at age 2.