Best time to chop and drop for maximum N yield is when the plants start to flower. (Or so I'm told). Or you use the pragmatic approach. Chop and drop when you have the time and it isn't raining!
I take it I only slash it, and dig in the cut part into the soil... to let the plant regrow? Or is it the whole plant? Do I re-mulch it? Or if I let it flower then seed, will it reseed for next season? or would i have to collect and store the seed?
Depends.... I've seen all of the following approaches discussed - cut the tops off, leave them on the ground as mulch and let it regrow and repeat. That gives you more mulch for your initial investment, but will be slower to return N to the soil. Depending on what you are wanting to plant you might not be able to put your next crop in because of competition. turn the whole plant into the soil. Faster return of N, but no mulch cover for the soil, bare ground. Able to plant anything you like in the clear space. Let it set seed and drop seed naturally to resprout. Lowest input of human energy with repeat cycles of fertility. But most of the N will gas off as the plant dies and you'll be left with dry brown carbon rich material. Let it seed and collect seed, store and replant. More human energy, increases yield (you get more seed than you first planted - which is handy if you want to cover a larger area next year), can plant in another part of the garden of your choice, but same issues with N. You might be able to get a feed out of the crop too depending on what it is. So depends on what you are trying to achieve with your green manure crop. Personally I use the cut it and leave it on the ground then regrow and repeat approach most as mulch is what I need. I also use the let it grow and then stick the chooks over it in a dome and let them eat it and turn it into eggs and manure approach! That gets the N level up fast too.
I'm a chop and drop fan. I've read that there is no real added benefit to tilling under in terms of extra N but I can't find the original study to verify this. Most sources say chop as the crop comes into flower to maximise nutrient catch. Seems reasonable. Do you get good frosts there? One of my favourite ways to mulch a garden is to plant frost tender annuals like sorghum and cowpeas in mid simmer. They grow quite well then get killed off when the frosts begin. The easiest chop and drop method I've come across. Neither cowpea nor lupin will self-seed well enough to give good cover the following season, at least they have never done so in my garden. You could chop and drop most and keep some back for seed which is fairly easy to collect and clean. You could use the seed either in the same patch or elsewhere. If you are trying to build resources though you might be better off leaving the lot for seed this time round. You won't get quite the same benefit as you'll be taking away some nutrient with the seed but you'll get a decent amount of seed for future use for not too much effort.
Hi all, Its been a while and thought I will give you all an update where I am at. check out the pics Week 9 - early June, it got to -1 so I bagged up my trees. View attachment 1776 Week 18 - cowpea is amazing!!! can you see the bags? Next year I wont bother bagging the trees as the cover crop - covers them. View attachment 1775 I decided to let the cowpea go to seed so I can collect the seed for next winter. And the amount of bees who are getting fed is well worth it. I did throw 8 kg buckwheat 3 weeks ago, but still can't see any seedlings. I am wondering if I should make the summer crop lupin. I really need a cover crop as we are still based in Brisbane and I only get out to the property every few weeks. Thoughts?
Yup the cowpea sure is doing the job! You could try a mix like the following one from Eden Seeds designed for spring / summer planting - Alfalfa, Beet, Broad Bean, Buckwheat, Cow Pea, Endive, Maku Lotus, Medic, Millet White, Millet Jap, Mung Bean, Mustard, Purslane, Radish, Soy Bean, Turnip, Vetch, Basil, Dill, Coriander, Fenugreek, Rocket. You could even eat half of them!
3rd year update.... Hi, It's now coming into the third year and it looks a lot different. The grass in the paddock is almost as tall as me, and very good at tripping me over. Thanks to the amazing wet summer and autumn we had. The mound is covered in long grasses, lupin, cowpea, eucalyptus leaves (mulch) and weeds. Over the years I have thrown clover, millet, buckwheat, Linseed and mung beans so that is in there too somewhere. I just did a small chop and drop of support trees. And left the mound covered as we are due for frost soon. I counted at least 10 different food trees species thriving. (That I could find) The support trees are large and have more seeds on them than I could possibly pick. In the photo the mound is green. The ground grass is brown. So the Swale is working. I will get more clearer pics, especially in spring when the grass is chopped and drop for mulch. Overall it's messy and untidy... And I love it! :grin: View attachment 3032
No, just the ones that are in the paddock that helping (out of control ) to cover the mound. Once the frosts are over they will be chopped and dropped as additional mulch.
