Green Manure?

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jemberelli
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Green Manure?

Post by jemberelli »

I have 2 (very) raised beds that are used for veggies. I have decided that instead of growing some late crops, I will have a go at green manure to give them a really good start to the spring growing season - or at least that is how I think it should work!

My questions is, is it worth doing or should I just plant up with something 'wintery'? If it is worth doing, what is the best crop to use? I have read that mustard is good but also clover and a multitude of others!

I am no Percy Thrower and this has just confuddled me!!
No girls at the moment but look forward to getting more in the future. Proud mummy to Hector, a Bedlington Terrier x Jack Russell
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rubyhen
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Re: Green Manure?

Post by rubyhen »

Am also considering green manure.

If you've got two beds you could do an experiement and green manure one and do some winter veg (hardy leaves under cloches?) in the other one.

Would be good to know what green manure other laners recommend.

Ruby
:-D
5 hens: Keira, Dot, Beryl, Kylie and Magda.
RIP: Ruby, Ginger, Tilly, Meg and Phyllis.
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jemberelli
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Re: Green Manure?

Post by jemberelli »

Hmm still not sure what to do but thanks for your reply Rubyhen! I will spend some time googling and let you know what comes out on top as suggestion for the green manure x
No girls at the moment but look forward to getting more in the future. Proud mummy to Hector, a Bedlington Terrier x Jack Russell
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lancashire lass
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Re: Green Manure?

Post by lancashire lass »

If you have heavy clay-like soil, an empty bed over winter can get knocked back by heavy rains and become saturated and waterlogged which means the soil stays cold for longer in spring and delays seeds from germination - also, you shouldn't dig saturated clay soil as you will compact it more. Sandy soil is poor at retaining nutrients which can get washed away, and in summer does not retain moisture very well. So in both cases a green manure will definitely help. Dig it in in early spring and it will help to open the soil up with the vegetable matter, and then it will compost down and provide nutrients. Ideally you shouldn't plant eg potatoes for at least 3 weeks after (bear in mind a cold soil will slow down the composting period), and at least 4-5 weeks or more before sowing seeds (the composting down process can prevent germination and/or good early growth as it robs the nutrients from the soil until it is completed) Some green manures are better grown over the summer period as they will not survive winter. In all cases, a bed needs to be free of perennial weeds (dock, dandelion, bindweed, marestail etc) otherwise you will simply chop up and cultivate the roots from digging the green manure into the soil.

The best manure for heavy clay soil is rye grass (Forage Rye/Hungarian rye grass) - it is also one of the best to improve the nitrogen level in soil. However ... it is extremely hard work to dig in but there are ways round it. First, you can strim the top leafy growth then cover the area with black heavy duty plastic/weed suppressant and leave for a few weeks so that it dies back then it will be easier to dig it in like compost. Rye grass is sown between August and October, and dug in from late February (or any time after before it goes to seed!)

If you are plagued by wireworm and other pests that affect potatoes, the best thing to grow is a mustard (Caliente Mustard or White Tinsley are the main varieties that are sold as green manure) Mustard is not that cold hardy so perhaps not the best to grow over winter except in mild areas and maybe use as a late summer/early spring sowing. Mustard is a brassica so if your garden/plot is known to have clubroot then do not grow it (you can lime the soil to raise the pH but if growing potatoes afterwards, some varieties get very scabby looking skins). Also treat it as part of your crop rotation - do not grow cabbages, swede, caulis, turnips etc after. Sowing is any time of the year from March up to October and can be dug in within a couple of months (and before the flowers go to seed) so an early spring sowing might be best if opting to sow on a bed for potatoes, and delay planting until end of May/early June. When mustard is bruised/crushed, it releases biofumigant gasses which can knock back soil pests - to be effective though, once you start to cut back and dig in you need to do it within a few hours on the same day. Cover the bed immediately with a plastic sheeting and weight it down so that the gasses are retained and keep on working over a couple of weeks.

Another useful green manure group are the legumes - winter tares, lupin, alfalfa, yellow trefoil, forage peas and forage beans. Most are winter hardy but do not endure extreme cold. Legumes are good at fixing nitrogen (nodules on the roots) In the same group are the clovers (red, white, crimson) which are also good at fixing nitrogen and have deep roots. It is recommended for sandy soils. Clover can be sown any time from spring until late summer and like other legumes it doesn't tolerate cold winters.

Phacelia tanacetifolia is a quick growing green manure and can be dug in between 1-3 months of sowing. The roots help soil structure, and the dense foliage helps to suppress weeds. It is also fairly winter hardy so a good choice and suitable for most soil types. If left to flower in spring it has pretty flowers that attract bees - however, beware that it readily self seeds so best to cut back before flowering. Sow anytime from early spring to late September.
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jemberelli
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Re: Green Manure?

Post by jemberelli »

What a very thorough reply, thank you so much! Plenty of food for thought there )t'
No girls at the moment but look forward to getting more in the future. Proud mummy to Hector, a Bedlington Terrier x Jack Russell
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rubyhen
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Re: Green Manure?

Post by rubyhen »

Thank you very much LL!

I think the final one you mentioned will be ideal for me so I will try and get some in soon and hope for a mild winter - we must be due one.

Ruby :-D
5 hens: Keira, Dot, Beryl, Kylie and Magda.
RIP: Ruby, Ginger, Tilly, Meg and Phyllis.
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