Mulching with dead weed

[Carlita]

Hi

I am brand new to this forum. I live in Melbourne's inner west. I am also pretty new to gardening. So I am probably going to ask a lot of questions, though will try to find out things for myself by general reading first!

Anyway, this is my question as pertains to this topic.

I have a huge pile of old, dead kikuyu weed which I am wondering if I can use for mulch. Now, when I say old, and dead. I mean...like..it's been in a pile for over two years and has not sprouted or grown shoots out or anything like that. It does seem to be quite *dead*. But I don't know if it could still contain seeds, all the same, that might come to life once watered and near soil/nutrients.

The stuff grows like mad in my yard. What I was going to do is cover weeded, composted and fertilised beds with news paper, and overlay the newspaper with the dead kikuyu as mulch. An old permaculture idea I picked up (well, the newspaper bit) long time ago.

Thanks for reading.

[Newt]

Hi Carlita,

When you say you "live in Melbourne's inner west", I'm guessing you mean Australia.* You might want to add that to your 'location' in your profile for later reference when you have questions.* :)*

As to the kikuyu, I'm thinking it's a grass known as Pennisetum clandestinum.
http://en.wikipedia.org/wiki/Pennisetum_clandestinum

When you make a pile of weeds and they sit for a long time, if the pile heats up enough to kill the seeds, then it's safe to use it as a mulch or soil amendment.* You don't say if you've turned the pile in the last two years, which would help aid in the decomposition, or if the pile is in direct sun enough to heat up and kill the seeds.* I would suggest you first turn the pile, wait a couple of weeks and see if anything sprouts and go from there.* If what is in the middle of the pile looks like soil and has that earthy smell that isn't musty from moisture, you can probably use it.* Putting down about 6 layers of DAMPENED newspaper first will be helpful if any seeds should sprout.* Then you will be better able to pull the grass out.* I mentioned to dampen the newspaper so you won't be chasing it all over the garden with the first breeze, giving your neighbors a giggle like I did!* :shock:*

You might find this site on lasagna composting aka sheet composting, helpful.
http://www.motherearthnews.com/Organ...Gardening.aspx

Newt

[Carlita]

Hey Newt!

*My apologies re not stating my general whereabouts. For some reason, I thought this was a specifically Australian site, probably because I hit on it in google under a garden forums + Melbourne Australia search and it was pretty high on the list. Doesn't matter...it looks a really good site, anyway! So, yes, you're right...I am in Melbourne Australia!

*Yes, that's the stuff in the website you point to. Only mine looks more like this, though not quite such a lush green:

*http://www.calflora.net/bloomingplan...kuyugrass4.jpg

*Mine, in parts, is also a lot 'tougher' than that looks, but that's partly because I let it go for way too long!

*Thanks for the advice.* I will do as you say and turn it and wait. I had not turned it. Just left it in a corner of my yard, pretty shady really. I don't have much room, at least in the front yard, to put it elsewhere and it would be no easy feat to get it round the back either; it's just the way my (rental) property is set up.* It should have heated up pretty well, all the same, since it IS in only a semi-enclosed, outdoors space, and has been through a couple of stinking hot Melbourne summers!

*Yeah...I've done the newspaper thing once before, and quickly found it had to be wet down as soon layed!


Thanks again!


*

[Newt]

Carlita, you are so very welcome!* Glad you like our site.* :)*

I had not turned it. Just left it in a corner of my yard, pretty shady really. It should have heated up pretty well, all the same, since it IS in only a semi-enclosed, outdoors space, and has been through a couple of stinking hot Melbourne summers!

It's the interior of the pile that needs to heat up.* Several factors will allow that to happen that include the size of the pile, a sunny spot and enough moisture. I'm glad you're going to give it a turn and see if anything sprouts.* Some seeds can stay viable for a very long time.

This site gives info about Pennisetum sataceum (fountain grass), a relative of Pennisetum clandestinum (kikuyu).* The bold is mine for emphasis.
http://ucce.ucdavis.edu/datastore/de...&usernumber=66

*

Fountain grass can reproduce by either fertilized or unfertilized seeds (Simpson and Bashaw 1969, Dujardin and Hanna 1989). Fountain grass is apomictic, meaning that it can reproduce asexually by producing seeds from the cells of female plants other than egg cells (Simpson and Bashaw 1969, Dujardin and Hanna 1989). Seeds may remain viable in the soil for at least seven years (Tunison et al. 1995).

I'm glad you are going to turn it and wait a bit to see if any germinates.

Newt