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I'd Like to Use My Compost for Seed Sowing, but It's Full of Weeds.

11 years ago


This is a very, very easy fix.

I have used homemade compost to sow seeds in. Compost is great, it's rich in nutrients and retains moisture very well. The only drawback is that it can also contain plenty of seeds.

It's actually really easy to kill those weed seeds. I fill a 5-gallon bucket halfway up with compost (or you can use whatever container you have on hand that you think is fine.) I have that bucket of compost on the patio outside my kitchen door. Inside the kitchen I've got a full kettle on to boil. When I hear the kettle whistling I take it off the flame and take it outside and pour that boiling water into the bucket of compost.

Then I put a lid on the doesn't have to be on tight, it's just to help hold the heat and steam in as long as it can. The boiling water and steam will kill the weed seeds. If you don't have a lid for the bucket then use a large piece of aluminum foil, or you can even use an old towel or blanket draped over the top.

I let the bucket of compost sit overnight so it's cool when I use it the next day. I can now use the compost for sowing seeds confident that the weed seeds have been killed. Also, another benefit of the boiling water treatment is that it will kill any soilborne diseases that might exist in the compost.

The method may be down-sized and used with small individual flats or cell packs. Remove the coursest pieces of compost to create a consistantly textured medium and fill seed sowing flats with it. Place a compost-filled flat in your kitchen sink and slowly and carefully drench the compost with a steady stream of boiling water from the tea kettle.

Some flats are made from very cheap and thin plastic and the plastic might warp from the heat....experiment before hand to assure success. If the plastic of your flats is too susceptible to heat then place the compost first in a metal colander, scald with the water, allow it to drain and cool overnight, then fill the flats with that.

Good luck with your seeds!



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