My sister bought a pickup load of compost from a nearby vendor and it has all kinds of weeds sprouting up in it. (It is still in a pile with a tarp over it.) What can she do to kill the weeds before she puts it in her flower beds and on her lawn?

Thanks,
Kathy

Sounds like the compost vender was not a real good one...

Only thing I can think of is to sift it-what a pain! But I have a neighbor who sifts hers! Just thru a screen in a frame.

Patty

You might want to compost it again. Make a pile & add dry or liquid molasses every foot or so. Make sure that the mix is moist & let it get hot which will kill any seeds in it. Ck posts especially from Captain Compost for add. info. Sifting will get rid of large chunks but not seeds.

I totally agree. There is nothing wrong with "re-composting" any potentially weedy composting product, or any composting product that contains potentially slightly mild toxins or pathogens.

The secret is to speed up the growth and digestion of all the beneficial aerobic microbes and other aerobic biology that is in the soil or compost, in order to speed up the maturity and sterilation of the compost. I do this by using molasses or sugary products and high nitrogen manure or compost teas as compost activators.

The extra sugars supply extra energy and carbon for the microbes to eat.
The extra nitrogen helps increase the microbial growth and increase internal compost heating temperatures for "sterilizing" the compost.

I use my best mature compost as a soil amendment, or in aerated compost tea recipes for foliar and soil drench appilcations.
I use any slightly undone compost as a mulch or as extra organic matter to start new no-till raised beds or lasagna gardens.

Happy Gardening!