[Joel_BC]

For years I've used fall rye as a cover crop on our larger garden: sandy-silt mineral soil, well drained, cool/cold winters. We add rotted manure, compost, and mineral amendments during spring. With the rye as the cover, I've tilled it in, in mid spring after snow-melt and drainage time. The benefit has been the organic matter from the grass and its roots.

But I dislike the extent to which the rye comes up during the year, even after a tilling or two. For that and other reasons, I've been thinking of trying forage/tillage radishes as a cover, instead, as my info says it will: winter kill; loosen the soil pretty deeply; and put quite a bit of organic matter into the soil. In our climate, it would get about six weeks, at least, before hard frost would kill it. There is little to no problem with flea beetles in our region in the fall.

Do the rotting radishes tie up too much N in the early portion of the next growing season? Also, I do wonder if tilling the radishes in, in the spring, results in a field that smells strongly of rotting brassicas!?

I'd appreciate hearing about any experience (pro's and cons) of tillage radishes as a cover in an organic-cultivation system. Thanks.

 

[Slatewiper]

I've used fodder radish as a cover crop for a while now. It will winter kill when the temps get in the mid 20's and by the time spring rolls around there is not much left to tie up any nitrogen.

The thing you have to watch out for is to not plant it too thickly. If you do the roots won't have a chance to fully develop and you'll miss out on the best reason to plant them. Also I just let them rot in place and don't worry about tilling them in.

I was somewhat disappointed in that because they break down so quickly, even in winter, they don't provide the soil protection I like to see in late winter-early spring. I've been toying with the idea of planting them with oats due to the fact the oats, which winter kill around 15-17 degrees, provide longer lasting protection. I'm just not sure what proportions I should use.

 

[Randy Rooster]

Crimson clover makes a good winter cover here but here at least it needs to be tilled in to kill it in the spring and before it sets seed or it can become a weed.

 

[Joel_BC]

Slatewiper, thanks for the gneral info from your experience with tillage radishes.

I was somewhat disappointed in that because they break down so quickly, even in winter, they don't provide the soil protection I like to see in late winter-early spring. I've been toying with the idea of planting them with oats due to the fact the oats, which winter kill around 15-17 degrees, provide longer lasting protection. I'm just not sure what proportions I should use.

Here the protection of the soil seems to come from the layers of snow that we get. It's more the subsoil break-up, the food for the worms and other soil life, and general carbon content that I want.

Do you get a lot of cold without a snow cover in your location?

 

[haley1]

I was wondering about the smell too, since it is too late to plant here for fall I was thinking of broadcast spreading in very late fall so they grow in spring and die/ rot in summer. This is just in an old field to build it for the future

 

[Gretchen Ann]

I plant field radishes in my garden every year. I planted the first half of the garden the 1st part of August. That is where the early crops were, garlic, onions, peas, broccoli. I just use my garden seeder.

I planted more today, potato ground, green bean ground. I like to plant the seed as soon as a crop comes out, I like the plants to get big and roots go deep.

I have never noticed a smell as they decompose.

As far as broadcast spreading in late fall, they will come up in the spring and grow and go to seed, but they don't die down, at least mine don't. I always have some seed that didn't germinate in the fall that comes up in the spring. If isn't in the way, I just let it grow.

 

[Slatewiper]

Slatewiper, thanks for the gneral info from your experience with tillage radishes.

Here the protection of the soil seems to come from the layers of snow that we get. It's more the subsoil break-up, the food for the worms and other soil life, and general carbon content that I want.

Do you get a lot of cold without a snow cover in your location?

We do. It can frequently get down to zero with no snow cover at all. We can also get pounding rain after the temps rise a little bit in late winter, which is why I need the protection.

If you're looking for something to break up subsoil you might want to try sorghum/sudan grass. It grows about 8 ft tall and if you cut it back once or twice it forces the root system to get bigger and go deeper. Cutting it also makes it send up more shoots so that it gets so dense nothing else can grow which makes it a great smother crop. It's heat loving though so around here June 1st is about as early as you want to plant it. If you can give it two months to grow you'll really be surprised at how well it breaks up tough soil.

 

[MDKatie]

You are going to have to plant them yesterday if you want them to get any good growth. The earlier the better for forage radishes. Here in Maryland, lots of farmers are starting to use them alone or in a mix with a small grain for cover crop.

I think there was only one year where it didn't get cold enough to kill them, so farmers had to work them up. Last year they were dead by December pretty much. There is definitely a smell if they die and then it warms up just a tad....smells like cabbage, but it doesn't last terribly long. Edited to add, I'm talking about hundred acre fields smelling. A garden probably wouldn't be very noticeable at all.

The state of Maryland recommends a seeding rate of 10-12 lbs per acre.