Planting Green: Why Do Farmers Plant Green?

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- Pennsylvania farmers have started planting green.

This is when a main crop, typically corn or soybeans, is planted into a living cover crop.

Hi, I'm Heidi Reed, a Penn State Extension agronomy educator, and I would like to talk about how farmers end up realizing the benefits of planting green.

No till farmers more commonly kill cover crops with an herbicide about two weeks before planting the main crop into dead cover crop residue.

In this photo, the living rye cover crop remains on the left with the dead rye residue on the right.

Planting green, on the other hand, requires the main crop to be planted while the cover crop is still alive as you can see here.

The crimson clover cover crop is still green.

It will be sprayed within a few days after this planting operation.

Farmers plant green to get more out of their cover crops, though specific reasons vary from farmer to farmer and boil down to about four: necessity or accident, soil conservation and health, soil moisture management, and slug management.

Let's start with necessity and accident.

Some farmers start planting green due to uncooperative spring weather or time and equipment constraints and then find it to be a better way to manage crop health going forward.

Sometimes you are forced to spray after planting as Leroy describes here.

- I've started planting green probably 25 years ago mainly because I was a sprayer person and my helper was a corn planter person and I was also the dairy barn herds person so he would get way ahead of me in planting and therefore I ended up spraying after he planted.

- [Heidi] Lucas wanted green matter for slugs to feed on rather than his main crop.

- It was kind of by accident and it all revolves kind of around your study with the slugs and I think with (mumbles).

Planting green started with wanting to have something green for the slugs to feed on and so we started to let the cover crops grow to plant into which in turn learned how we can build bigger biomass and organic matter and soil.

- [Heidi] Too much rain forced David Hernley to plant green and now he loves it.

- The first time I planted green was not really intended to be that way.

It rained that spring and we didn't get our cover crops killed so we planted green and I loved it right from the start, that first year.

It was amazing.

From then on, we've just been doing it.

- [Heidi] Planting green allows farmers to take advantage of maintaining living roots in the soil for more of the year and utilize the biomass gains cover crops can achieve when they are most actively growing in the spring.

Next, farmers plant green for soil conservation.

Research has shown that more cover crop biomass reduces soil loss and improves soil health by reducing bulk density and increasing soil carbon, water holding capacity and water infiltration.

Here you can see good soil structure, worm holes and roots from the cover crop.

David further explains how his soil health benefited from planting green.

- Now that we've done it, we're learning more about why we did it.

We didn't really know why we did it to start with, but now we're seeing the benefits with soil health and this is really changing for us.

- [Heidi] Some farmers have also found that planting green can help manage excess moisture in wet springs.

As cover crops grow and transpire, they draw water from the root zone and can significantly reduce soil moisture.

This can improve seed bed conditions for planting which can be a great benefit in wet springs.

Then as the cover crop dies, the massive biomass residue insulates the soil from sunlight and traps moisture in the soil which can benefit the main crop during dry spells, a common occurrence in Pennsylvania, as seen here.

Danville farmer Tyler Buck explains how he has benefited from retaining this moisture from planting green.

- It's proved to be beneficial in wet years and dry years.

We can get into plant sooner and it'll be more moisture in the ground later when the water starts to shut off.

- [Heidi] Finally, planting green can help to manage slugs by providing alternative food for the slugs so the corn and soybean seedlings are less likely to be targeted and the living cover also provides habitat for slug-eating predator species like ground beetles and spiders.

Here, Lucas Criswell and Steve Groff further describe the benefits of planting green for slug control.

- Slugs started it personally on our operation.

We were planting covers and burning them off and making it brown.

And then we found that slugs just want something to eat too so we left something green and it provided huge benefits, then compounding from there.

It's just kind of been endless I guess.

- Cover crop benefits now affects the insect population and the slugs and that certainly has been a challenge for all no tillers and cover croppers.

And by having green plants still there in the field, the slugs tend to stay in that rather than our cash crop.

So that's certainly a benefit that we have seen in doing that.

So that's some of the main reasons we've been doing it.

- In the end, while planting green or planting seed into a cover crop can solve many problems, it requires close attention to crop management.

The individual strategy will vary from farm to farm and is not one size fits all.

But whether by accident or on purpose, Pennsylvania farmers have discovered the many benefits of planting green.