weeds, compost and the odds

[dave45]

My veg patches are under constant threat from weeds... docks, nettles. marestails, buttercups, brambles, bindweed, couch grass the works.... yet I don't compost the stuff I pull out "as it may contain weed seeds and my compost heap may not get hot enough to kill them"

in view of the overwhelming assault that still results from airborne weedseeds, underground weed tentacles etc should I just chuck them in the compost heap anyway, to reclaim their nutrients, on the basis that I'll still end up with the same amount of weeding work whatever I do?

[chuck_n_grace]

Hi Dave,
Last year we added lawn fabric to act as a mulch. It did an excellent job at keeping the weeds at bay. The drawback was that it was a hassle adding compost and fertilizer. This year no lawn fabric, and we are pulling grass weeds daily.

Because my neighbors now send me all of their lawn clippings, including weeds, I have given up on sorting out the weeds. So, I'll continue to pull weeds until I develop a clever mulching system that allows me to kill the weeds around veggies while allowing me to add compost easily.

I am favoring the nutrient value of these weeds for the moment.

Regards,
Chuck

[niknik]

when I started , last year, I carefully dug up all the weeds ( mainly nettles) and made nettle soup fertilizer. I was worried , I might have done too good a job ........ no chance, nd wouldnt mangae to get any more .
i mainly just added everything to the compost heap, and a few did grow through!. as did some potatoes, justfrom peelings!

I then let them dry first in the sun, on the paths first, didnt make much difference. This year, I´m putting everything ( including slugs, caterpillars) into a large bin of water to rot down first, then adding to compost. I figured t hat if nettles rot down and leach oout nutrients into the water, so must everything else, and cant imagine it will do any harm!


Apart from which there always be more seeds brought in, eitherairborne orby insectsanyway......
this year, I´m finding some catus/ succulent type things growing, that have neverbeen herebefore, and I certaily havent brought in! Dont know ifthey´d countas weeds, butcertainly unwanted! but I have potted acouple up , to see whatthey become!

[wulf]

I'm doing the water bath thing as well for anything that is (a) perennial (and liable to grow back from a small piece of plant material) and (b) setting seed. As well as killing the weeds off, it also gives you a concentrated liquid that can be watered down and used to feed the soil.

Any idea how long things need to be submerged for complete cell death to occur? Even after a week or so, the resulting green-brown goo smells pretty rank.

Wulf

[niknik]

I read somewhere ( i think ) that soaking nettles was for about 6 weeks!.... really need 2 or 3 containers on the go at any one time!

I have also found its best to leave uncovered.as with lid on , I have had a mould growing, and smells even worse! the trouble is, the dog drinks out of the uncovered one ( no obvious ill effects though)

[gregorach]

I compost more or less everything. Given the magnitude of the seed bank that's already in the soil and the rate at which weed seeds blow in, I don't think it's much worth worrying about. It's only really a problem if you want to use your compost for seed sowing as well (which I do, but I just about cope). I figure the more stuff you put in, the greater your chances of reaching the temperatures needed to kill it all off. I keep my compost covered though, so the weeds die through lack of light. And I work on an annual cycle, so they've got plenty of time to die and rot down.

The one problem that I really noticed last year was when using my own compost to grow salad leaves in trays... The ideal there is just to be able to cut the whole lot with a pair of scissors, but it doesn't work so well if you've got grass, docks and nettles in there too.

[hedgewizard]

Learn to 'hot compost' to kill the roots and seeds. Or...
Drowning weeds takes two weeks and yes, it smells horrible. Or...
'Steam' them by putting them in a black bin bag (tied) in the sun for a week. Don't breathe the air in the bag when you open it as it's going to be full of spores. Or...
Sterilize the compost with heat before you use it. Not terribly green though!

[gregorach]

Learn to 'hot compost' to kill the roots and seeds. Or...

It's the simple practicalities of it I have trouble with... As as I understand it, you really need a rather large amount of material all at the same time, whereas weeds come out of the plot at a steady trickle. Also, I make up my main compost heap at the end of the season when I've got the most material available, but at that time of year the weather isn't exactly conducive to getting it good and hot.

[grahamhobbs]

I stumbled on the black bin bag method many years ago, it's very effective if you can fill the bag in one go with a good proportion of moist green stuff and leave it in the sun, it'll compost in a couple of months. Problem is having a space in the sun where you want to leave a load of black bin bags.

I have to admit now most things go on the compost (dandelion flowers/seed heads go into water) and is just left to rot for over a year. I can't be bothered to turn it as all the books say, that's just too much hard work. If you use the compost as a mulch any weeds soon germinate and you can easily hoe them off. Perenial weed roots seem to be killed off although cccaisionally you get bindweed growing in the heap but their white roots (the rich soil makes them plump and straight) are easily spotted and removed.

I am in the process (eh hhmm, have been for several months now) of assembling a rotating composter made from an old metal drum with a short scaffold tube through the middle. Just needs the supporting frame setting up. Going to give this a try for rapid composting of particularly seedy weeds or grass cuttings.

[Odsox]

I am in the process (eh hhmm, have been for several months now) of assembling a rotating composter made from an old metal drum with a short scaffold tube through the middle. Just needs the supporting frame setting up. Going to give this a try for rapid composting of particularly seedy weeds or grass cuttings.

Please let us know how you get on Graham.
I've been thinking of this for several years now, but have yet to hear from anyone who has actually used one. The trouble is they are expensive to buy, especially with shipping over here, and I have yet to find any suitable drum to make one from.
If I was sure that it worked I would make one out of timber ... slats nailed on three discs of ply sort of arrangement.
But I would really like for someone to tell me it's well worth it before I start.

[nyghtowl]

As long as the "weed" has not gone to seed (post-flower) it is fine to compost.
We compost anything that is green and in the wrong place.
Also - no plant can survive constantly having its head cut off to ground level - tedious? yes - but effective in the long term.

[grahamhobbs]

Also - no plant can survive constantly having its head cut off to ground level - tedious? yes - but effective in the long term.

But you have to cut it every time before it reaches 10 to 15cm tall, up to that point it is taking energy from the roots after that it is feeding the roots.

thanks Odsox, that's the kick up the butt I needed,will try to finish it this weekend.

[hedgewizard]

Learn to 'hot compost' to kill the roots and seeds. Or...

It's the simple practicalities of it I have trouble with... As as I understand it, you really need a rather large amount of material all at the same time, whereas weeds come out of the plot at a steady trickle. Also, I make up my main compost heap at the end of the season when I've got the most material available, but at that time of year the weather isn't exactly conducive to getting it good and hot.

Yep, me too. That's why I gave other options! Oh, and I forgot my new addition: a compost tumbler from Ebay. Anything weedy goes in there, then I add some sawdust (from a local workshop) and tumble daily for two weeks before moving it to the regular bins. Gets pretty hot!

[Millymollymandy]

I chuck all weeds in apart from bind weed and nettle roots and rip off things like dandelion roots.

If I didn't put weeds in I would be seriously lacking in green stuff to go in the compost! It doesn't make a blind bit of difference to the annual weeds which come up whether the compost is dug in or not. I just hoe off what I don't want to grow (I do want dill, coriander, red orach, lettuce, verbena bonariensis and various other 'weeds' ).

[Henwoman]

I put everything in my compost bins. All weeds, grass clippings and the straw and muck from the hen and rabbit houses. It never looks as if it's going to compost down, but the following spring there it is - pure gold waiting to be added to newly dug beds and be forked in. Sometimes there are a few big bits which I chuck out, but usually it's all fine stuff.