What cover crops grow in mulch (pacific NW zone 7B)

Hey all. My garden/food forest in zone 7b (pacific nw) is growing and expanding in complexity each year! This is our second summer and things are looking great. We have a couple large areas ( 10' x 20') that are covered with aged mulch. I put the mulch down to smother the grass because the area will eventually be garden space for veggies and shrubs, plus hate mowing. We don't have the time this year to turn the area into a "garden bed" so it is just happy mulch and nothing else.

My question...what seeds can I broadcast and rake in to grow in the mulch in zone 7b (coastal pacific nw washington) I figure I would chop and drop before it goes to seed. One concern is that many seeds may not germinate very well in the rough and large wood chips.  Does anyone have experience with this or ideas to share. Thanks community! (Zone 7b)

Hey Chris,

You're right, since the woodchips are such a large sized mulch, it can be hard for a lot of seeds to germinate.

I've had good success planting in "pockets" when I've used thick mulch before. The mulch can be pulled aside and the seeds planted in the soil, and when the plants get some size on them, the mulch can be moved back around the plants.

Hope this helps a little, sounds like you've got some good growing areas!

Hi, Chris

Are you concerned that grass will take up residence in the chips or just wanting to try to grow something that you can chop and drop?

My thought was to plant daicon radish.

Here is a thread about planting roots crops in wood chips:

https://permies.com/t/85187/Planting-root-crops-woodchips-dig

It’s not a cover crop but I’ve had good success with strawberries in mulch. The runners root easily on top

Steve, that sounds like a decent idea. A little more time consuming but probably would have a higher chance of success. I may try that for one are.

Steve Thorn wrote:Hey Chris,

You're right, since the woodchips are such a large sized mulch, it can be hard for a lot of seeds to germinate.

I've had good success planting in "pockets" when I've used thick mulch before. The mulch can be pulled aside and the seeds planted in the soil, and when the plants get some size on them, the mulch can be moved back around the plants.

Hope this helps a little, sounds like you've got some good growing areas!

Anne,
I out some cardboard down first and then about 6 inches of mulch so hopefully the grass wont come up through. A little always does but that is easy the handle.

I mostly want to add more biomass to these areas because next your I will be planting vegetables in them for harvest, after i add more compost to it. Plus lush green plants look beautiful compared to mulch and woodchips!

I did diakon 2 years ago and they did great. I have loads of volunteers this year and every year in the future. So I was looking for something else this time. Hopefully something I can chop before it goes to seed!

Anne Miller wrote:Hi, Chris

Are you concerned that grass will take up residence in the chips or just wanting to try to grow something that you can chop and drop?

My thought was to plant daicon radish.

Here is a thread about planting roots crops in wood chips:

https://permies.com/t/85187/Planting-root-crops-woodchips-dig

Maybe some flowers? Any idea what can easily be broadcast?
I was also think I could lay some of the cloche cloth or greenhouse plastic I have. This may provide a better germination environment for the seeds and keep out the slugs and rabbits

Chris, I have very large mulch areas and have done a lot of tests. The common denominator for me has been large seed legumes. The nitrogen sequestration makes it hard on other plants. My favorites so far are Sesbania, cowpeas, Carolina lupine, and for a winter recurrent cover crop (assuming you put down new chips most years) vetch will help. If the chips are truly aged beyond a few years I suggest squash which will root periodically.
It will also act as a cover crop.

Best method of planting is to push the seed in with a dibble stick but can also be done broadcasting and then raking the mulch around a little to bury some seeds.

Tomatoes are a great space hog in relatively fresh chips if you can get them cheap they will fill a bed spaced every 5 feet !

Oh I forgot sunflowers. Had monsters in the chips- Russian mammoth

I might do a combo of methods. Some pockets with compost and some just broadcast. A few weeks ago my son was playing with some dried kidney beans, just pouring them between bowls, he is 2. He spilled a handful and I went back to that part of the yard a week later and they were sprouting and looked very happy. It was on some wood chips surrounding a tree. They were just store bought seeds. Maybe I will toss more of those out!

Tj Jefferson wrote: My favorites so far are Sesbania, cowpeas, Carolina lupine, and for a winter recurrent cover crop (assuming you put down new chips most years) vetch will help.!

Tj,  Where do you get these seeds?  I am recovering my backyard (about 1/3 acre) with fresh and thick layer of chips.
Thanks

So today on solstice I throw out a bunch of kidney beans, Lima beans, red mountain orach and pak choy. The orach and pak choy were from seeds I collected last year. Free seeds are the best! After throwing them out I raked the area. It would be great if some come up!

I may stop at the local garden store and grab a pound of feeder sunflower seeds. I am not sure if they will sprout. I don't see why not

Chris,

If you don’t mind doing just a little bit of work you might try a technique I use.  I also like to grow in woodchips and mine, especially if fresh, are typically fairly large.

My technique is a version of the fertile hole.  I call it the fertile trench.  I like to drag a hoe through the chips and make a trench about 2” deep.  I then backfill with topsoil, manure, compost, basically anything that makes a good bedding material.  Plant the seeds and cover with a thin layer of chips.  

I like quick and easy solutions when they are effective and this technique has worked for me.  Minimal effort for maximum output.

Hope this helps,

Eric

Thanks Eric, that sounds very easy.  I will try that on a different patch i have.

I think sunflowers would work. I have a ton of volunteers that came up in the wood chips in my garden this year from a half dozen plants I put in for the birds, last year, then pulled up and tossed on top of the mulch last winter. Some have gotten close to 12 ft tall and I haven't done anything for them since they've come up. The pollinators seem to really like them, as well.