Killing Weeds and using them as compost

[Crimson Castle]

Hello,

I'm thinking of using my weeds as compost. But my gardener told me to forget about it. He argues that its pointless placing the weeds into the compost bin and then using them as mulch (in three months time or so) because the seeds often don't die - and you end up seeding your garden with the darn weed seeds. He now insists that only lawn grass clippings get placed into the compost bin.... well that's another story.

In the ancient past I'd put the weeds into a concrete compost oven and cook and bake the darn things - then use it. But we are not allowed to do that now - due to council by-laws.

I thought of placing the weeds into a special big plastic tub in a far corner of the backyard- and then letting them soak in crappy water and some manure for a month or so. Would that help to kill the weed seeds?

Cheers,

Crimson

[Janet Baraclough..]

The message from "Crimson Castle" contains these words:

Just pull the weeds before they go to seed and you won't have a problem. I compost very nearly all mine except that little bulbous sorrel.

Janet.

[Phisherman]

Maybe, maybe not. Some weed seeds are exceptionally tough. I agree with your gardener. I leave my grass clippings on the lawn, with a mulching mower it quickly returns nitrogen for a healthier greener lawn.

[Andrew G]

It is pointless unless the heat created by your compost reaches above 60 degs celsius as that is usually what's required to kill seeds. As for grass clippings. Well they do heat up, but not all seeds in the clippings will die. Though there is no harm in having a bin purely for clippings then using them as mulch when they are well rotted.

Nothing that's 100% certain. Just bag them up and throw them out. You may be able to soak them in water and make weed juice, but careful to filter it properly to avoid any seeds getting through.

Good luck

[Doug Kanter]

You said "only lawn clippings". Why not raw vegetable scraps? What "council"? Condo?

[Crimson Castle]

The compost is a closed black bin with a lid. Its in an area that gets full sun but the earthworms hate it. I don't know about winter conditions but in Summer the ordinary temperature reaches 40C - it should be considerably hotter in the compost bin.

As for bagging the seeds etc.. I don't intent to keep seeds but when you place the copious amounts of weeds into the containers - it is simply too hard to sieve their seeds out.

Anyhow, I'll place them into plastic containers and let them rot in them in some obscure part of the garden for 3 months or so.... Otherwise, whenever I am digging a deep trench or something deep - I'll throw them in where they will prove to be of no use to anyone except the humble earthworm.

[Crimson Castle]

Yes, I forgot to mention I also throw in raw vegetable scraps. The laws in this land forbid open fires anywhere.

[Doug Kanter]

Open fires??? What's that got to do with compost? :-)

[zxcvbob]

Toss the seedy weeds in the lawn and mulch them up with the lawn mower. Garden weeds don't compete very well with healthy lawn grass. If some of them do sprout, they won't survive getting mowed down a couple of times.

You put grass clippings in the garden; it seems turnabout is only fair...

Bob

[William Wagner]

My father always burned bones before he add to our piles. Which we have had for awhile. Seems he thought it made the nutrients more available. Guess a lot like adding wood ashes etc.

Death and destruction is a way of describing the way we garden.

PS Got any fresh killed tree chips you want to dump on my yard?

William(Bill)

[William Wagner]

Sorry I neglected to add one item to the idea of death and destruction being central to garden stuff.

REBIRTH.

Seeds rot before they grow...Go figure.

William(Bill)

[Doug Kanter]

No chips, although the old lady across the street from my new house is trying to have her perfectly good sycamore murdered, in case you'd like to come to Rochester NY with a dump truck. One by one, I'm meeting the new neighbors. This one hobbled out yesterday to say hello. The first thing out her mouth: "Lemme tell ya about this damned tree. This has been the WORST year for it throwin' all that bark down & nobody can figure out what disease it is that's causin' it. And the town's no damn help! It's on their easement, and they won't come out & look at it". I tried to explain that the bark falls off those trees when they grow, like lobsters molting, and that the excessive shedding could be connected with the fact that we've had WAY more rain than usual this year. But no. Her tree is sick.

[Warren]

considerably

I think there may be a little misunderstanding here. When people speak of compost getting hot, the heat being referred to comes from the decomposition, not from external sources.

A pile of material with the right composition of carbon vs. nitrogen will get hot even if it's not in a container. On the other hand, if the ratio isn't close to right, decomposition will be slower, and not as hot even if you have it in a dark container in the sun. (Actually, if you have proper ventilation, the temperature inside a dark container won't be significantly hotter anyway.)

While it certainly is easier to get a hot pile when the ambient temperature is higher, you can still get a hot pile in the middle of winter.

And you're not going to see worms in a hot compost pile. They'd be baked. Worm composting is a whole different method. If you're trying to attract worms to a typical backyard composting bin, you'll be disappointed.

[Terry Collins]

You need a bigger bin. A 1 metre cube usually improves the composting far better than those plastic bins. The bigger mass can generate and keep more heat to kill the seeds.

And I have the same problem with grass seeds from grass clippings.

Other things you can fiddle with are; moisture level (you may need to add water) bit of lime (especially if you put in gum leaves) nitrogen (dynamic lifter is relatively cheap - add water).

[Holy Zarquon's Singing Fish]

We soak ours in crappy water for +- 6 months and then use the crappy water. Works fine.

[Phisherman]

It is interesting that when a compost pile becomes 1 cubic yard, it begins to "cook," but before it becomes that large it just does not want to heat up. I use 4-foot diameter bins made from 4' high rabbit fencing--works great. Strange to see steam pouring out of it in the middle of winter.

[The Watcher]

I take a long-term view of things, and know that I will defeat the weeds eventually. It's just a matter of persistence. I enjoy spending time in the garden, even time spent weeding. That doesn't mean I'll deliberately waste time weeding, but I do use weeded material in the compost. Once I even gathered up a pile of thistles(complete with seed heads), shredded them, and made compost from just thistles as an experiment. I watched the beds I used that compost on to see if any thistles sprouted there. None did. The compost did cook pretty good for the first few days after I ran it through the shredder.

[Janet Baraclough..]

The message from don' [e-mail] (The Watcher) contains these words:

Once I even gathered up a

There are many weeds which are particularly GOOD for composting because of the minerals they contain, and that includes thistles. Others are comfrey, bracken, nettles, seaweed and yarrow. If you have a good source of them growing wild close by, it's worth harvesting them to add to the compostheap.

Janet.

[Chookie]

Given that you have a black plastic bin, the bin should heat the seeds up enough to kill them. Secondly, consider how much work we are talking about here. Are the weeds you're gettign difficult to remove? If yes, then avoid composting the seeds (or letting the plants seed). Weeds that don't have seeds on should be fine to go into the compost.

THings that you really should NOT put into compost are thorny branches (the thorns don't break down) and anything showing signs of fungal disease.

[Crimson Castle]

Nope its just the usually dandylion stuff, and a wierd weed that has a white flower, has small "branches" that become pods and disintegrate, spraying the seeds everywhere, when you pluck them from the ground when the pods are ripe.